EXPT2151 Notes - Motor Skills Classification PDF

EXPT2151 Notes Week 1 Classification of Motor Skills Learning Outcomes 1. Describe and distinguish between key terms and definitions in the field of motor learning and motor control 2. Identify the factors that influence the performance of motor skills 3. Describe how motor skills c...

EXPT2151 Notes Week 1 Classification of Motor Skills Learning Outcomes 1. Describe and distinguish between key terms and definitions in the field of motor learning and motor control 2. Identify the factors that influence the performance of motor skills 3. Describe how motor skills can be meaningfully classified and how motor skill classification systems can assist with movement instruction 4. Describe different ways to measure motor skill performance Key definitions →Motor Learning - The acquisition, enhancement or reacquisition of motor skills →Motor Control - How the neuromuscular system activates and coordinates muscles and limbs to perform a motor skill →Motor Development - Development of human movement from infancy through to old age →Movements - Behavioural characteristics of specific limbs or a combination of limbs that are component parts of an action or motor skill →Motor Skills - Voluntary control over movements of the joints and body segments to achieve a specific goal Why distinguish movements from skills? - There are multiple different ways (movements) that can be executed to achieve the same goal (motor skill) - Movement instruction for a specific skill can be tailored to the unique movement characteristics of individuals e.g. appropriate modifications can be made if necessary Motor skills include aspects of cognitive and perceptual domains of skill →Cognitive domain - Knowing what to do - Knowing how to do it - Measure of success - knowledge and cognitive abilities →Perceptual domain - Ability to detect information - Ability to discern among sensory stimuli - Measure of success - sensing when and how to act →Motor domain - Doing it and doing it correctly - Performed in most daily activities - Motor skills are not performed in isolation - Measures of success - quality, speed, range of movement Three components influencing motor skill performance - Person: (who) - individual attributes - Task (what) - goals, movement demands, and perceptual demands - Environment (where) - environment in which a person executes the skill The classification of Motor Skills →Two methods of classification: →One-Dimensional Systems - classification on a continuum, rather than dichotomus categories - Size of primary musculature required - Stability of the environment - Temporal features of the skill →Two-Dimensional Systems - two dimensions influencing performance - Environmental demands - Action requirements Size of Primary Musculature →Fine motor skills - Recruitment of small muscle groups to achieve goal - Precision of movement is essential - Often requires good hand-eye coordination and dexterity (writing, drawing and sewing) →Gross motor skills - Use of relatively large muscle - Involve many muscle groups - Movement of entire body required to achieve goal - Force production required - Fundamental motor skills (walking, running, jumping, throwing) Temporal Predictability - Classification based on specificity of where the actions begin and end →Discrete Motor Skills - Clearly identifiable beginning and end points - Typically completed quickly →Serial Motor Skills - Series of discrete movements linked together - Can sometimes mimic a continuous skill →Continous Motor Skills - Beginning and end are arbitrary Stability of the Environment →Environmental Context - Specific physical location in which a skill is performed - Consists of three features - 1. Supporting Surface - 2. Objects involved - 3. Other people involved →Closed Motor Skill - predictable - Surface remains constant  - Object waits to be acted upon - Other people are stationary →Open Motor Skill - unpredictable - Surface changes - Object is moving - Other people are moving - Off the tee (closed skill) - Freely human pitch (open skill) Stability of the Environment →Closed Motor Skills - Performer initiates the movements involved in performing the skill when they are ready to do so (i.e. ‘self paced skill’) →Open Motor Skills - Performer must time the initiation of their movement with an external feature in the environment (i.e. ‘externally paced skill’) Two-Dimensional Classification - One dimensional classification does not always capture the complexity of many skills - Two dimensions classification system (Gentile’s taxonomy, 2000) →1. Environmental Demands - Regulatory conditions under which skill is performed - Relevant to how skill must be performed - Stationary or in-motion conditions - Inter-trial variability →2. Action Requirements - Body transport - Object manipulation Gentile’s Taxonomy - Originally proposed as a functional guide to assist therapists to assess patients movement problems, and select appropriate activities - Each category imposes a set of demands on performers in terms of number and type of variables that must be controlled →Therapists can use these categories to: 1. Evaluate patient abilities and limitations 2. Select a progression of functionally appropriate activities to help overcome deficiencies 3. Chart individuals progress of patients or students 4. Assess effectiveness of a rehabilitation or instruction program Gentile’s Taxonomy (Environmental Demands) - Taxonomy of motor skills based on the environmental context dimension of Gentile’s two-dimensions taxonomy Gentile’s Taxonomy (Action Requirements) →Action requirements - Body transport = walking, running, swimming - No body transport = standing, sitting, archery - Object manipulation = throwing ball, kicking ball - No object manipulation = single leg balance, running Assessing/Measuring Motor Skill - Two categories of motor performance measures →Performance Outcome Measures - The outcome or result of performing a motor skill →Performance Production Measures - How the nervous, muscular and skeletal systems function during the performance of a skill Variables Commonly Used to Assess Motor Skills - Reaction time - Error measures - Kinematic variables What is Reaction Time - Reaction Time (RT) - the time interval between the onset of a signal (stimulus) and the initiation of a response  - Movement Time (MT) - the time interval between the initiation of a movement and completion of the movement - Response Time (RT) - the time interval involving both reaction time and movement time; that is, the time from the onset of a signal (stimulus) and completion of a response Types of Reaction Time - Simple RT - the situation involves only one signal (stimulus) that requires only one response - Choice RT - the situation involves more than one signal and each signal requires its own specified response - Discriminaiton RT - the situation involves more than one signal but only one of the signals; the other signals require no response Error Measures - Error is a performance outcome measure, indicating the difference between the performance value and the target or goal amount - Error (or accuracy) can involve either spatial measures, temporal (timing) measures or both →Type of error - Absolute error (AE) - the magnitude of error without regard to the direction of the deviation - Constant error (CE) - the amount and direction of error and serves as a measure of performance bias - Variable error (VE) - the variability (or conversely, the consistency) of performance Kinematic Measures - Performance production measures based on recording the movement of a whole body, body segments, or an object - Kinematics is the description all motion without regard to force or mass →Types of kinematic measures - Displacement - change in spatial position of a whole body, limb or joint - Velocity - rate of change of displacement of a limb or object with respect to time - Acceleration - the rate of change in velocity during movement with respect to time Points for the movement instructor - Evaluate the learner’s achievement of the actual goal of a skill as well as the associated movements - Be aware that many motor skills it is possible for different people to achieve the goal of a skill by using different movements → find the movements that work best for each individual - Understanding different categorisation programs assists you to determine how different skills place different demands on the learner - Use of a taxonomy (e.g. Gentile’s taxonomy) assists with: - 1. Evaluation of a learner capability and limitations - 2. Planning progression of motor skills - 3. Evaluation of effectiveness of training or rehab program - Important to understand measures of success for performance of specific skills to identify and correct movement problems to enable achievement of a skill Measuring Motor Learning and Performance Learning Outcomes - Describe and distinguish between the terms motor performance and motor learning - Describe how motor learning is measured, and be familiar with the different types of performance variables and performance curves - Understand the terms acquisition, retention and transfer, and how they relate to motor learning Definition of Motor Learning - Motor skills are learned behaviours →Motor Learning - ‘A set of processes associated with practice or experience leading to a relatively permanent change in the capability for skilled performance’ - Schmidt - ‘A change in capability of a person to perform a skill that must be inferred from a relatively permanent improvement in performance as a result of practice or experience’ - Magill - This changed capability is then a permanent part of the person’s makeup and is available at some future time when that skill is required Definition of Motor Performance - Motor performance is observable behaviour - Motor performance refers to the execution of a skill at a specific time and in a specific situation - Performance may vary according to the specific conditions and situation under which a skill is executed, i.e. performance variables alter performance Comparing Motor Performance and Learning Performance Characteristics of Skill Learning - We generally observe five (5) performance characteristics as skill learning takes place 1. Improvement - performance is executed with a higher level of skill at some later time than at a previous time 2. Consistency - a person’s performance outcome and movement characteristics become more similar 3. Stability - the influence of pertubations (internal or external) on skill performance decreases as learning progresses 4. Persistence - the improved performance capability lasts over increasing periods of time i.e. the improvement in performance becomes permanent 5. Adaptability - performance is adaptable to a variety of performance contexts, i.e. the performance of a skill becomes generalisable to different situations Measuring Motor Learning - Motor learning cannot be directly observed but must be inferred from performance e.g. measuring levels of performance during practice of a skill - Performance can be illustrated graphically in the form of a performance curve - a plot of the level achieved on the performance measure for each period of time →Performance graph - Performance measured on vertical axis - Time or number of trials on horizontal axis The Shape of Performance Curves - There are 4 basic patterns of performance curves →Linear Performance - Learning occurs proportionally over time →Positively Accelerating - A large amount of learning occurs later in practice →Negatively Accelerating - A large amount of learning occurs only in practice →S-Shaped (Ogive) - Learning accelerates in the middle phase of practice Performance Curves Plateaus and Asymptotes - The negatively accelerating performance curve is the most commonly observed → this curve demonstrates the “Power Law of Practice” - The negatively accelerating curve indicates that it is not uncommon for a person to experience a period of time during which improvements seem to have stopped i.e. a performance plateau - It is important to realise that even though performance plateaus may occur, learning often still continues during this - An asymptote is an upper limit of performance that is considered the ‘best possible level or performance’ → as long as practice is continued, learning will continue to get closer to this upper limit Merging of Performance Curves - Performance curves may only reveal the initial phase of learning - In later stages of learning different shaped curves may merge into negatively accelerating pattern i.e. Power Law of Practice (i.e. performance asymptote) is eventually demonstrated Assessing Motor Learning - Measuring Art - There are three methods for assessing motor learning from motor performance observations - 1. Acquisition - 2. Retention - 3. Transfer - All three methods require repeated observations Acquisition - Refers to the direct measurement of performance - All practice attempts are assessed - Measurements represent any changes in performance observed over the course of practice - A series of acquisition measures may be graphed to illustrate changes in performance over the course of practice - this is the performance curve - May illustrate important features of performance → e.g. effect of various temporary performance variables (instruction methods, environment, motivation) Retention - Retention Tests refer to performance measurements conducted after acquisition trials - Retention tests should be performed after sufficient time, this allows any effects of performance variables to have dissipated - Retention tests only measure the permanent changes in performance, they are therefore a more accurate measure of learning than acquisition - Retention tests demonstrate the learning characteristic of persistence, i.e. the permanency of the changes Transfer - Transfer tests measure how effectively a person can transfer the learning of a skill from one condition to another - A measure of the strength of learning in terms of how adaptable the learning is to novel, non-practiced conditions - A measure of the adaptability or generalisability of learning Assessing Motor Learning - Each of the ART measures contribute something unique to our understanding of the learning process →Acquisition - Shape and rate of improvement  - Factors that influence performance - Consistency and stability of performance →Retention - Learning independently of temporary performance variables - Persistence or permanence of practice effects →Transfer - Influence of practice on strength of learning - Adaptability to other conditions Transfer of Learning - Functional exercise prescription is a form of transfer of skill learning from one context (i.e. practicing specific therapeutic exercises) to another context, (i.e. performing activities of daily living or workplace tasks) - When prescribing functional exercises, exercise physiologists and physiotherapists must have a clear understanding of the target skill and target context and specifically match the prescribed therapeutic exercise to these goals - Target skill → the real skill of interest during practice (e.g. specific workplace task) - Target context → the real situation in which the skill will be performed (e.g. work environment where speed or accuracy of performing a skill may be important) Points for the Movement Instructor - Good performance under certain conditions does not necessarily mean motor learning has occurred - Improvement and consistency during practice sessions may be artificially influenced by characteristics of the practice session, e.g. feedback and guidance →try not to always provide feedback, or physical guidance for every practice attempt - As people learn motor skills, they not only show improvement in their performance but also become more consistent in their performance, which is a sign of learning - Evaluation of retention and/or transfer gives a better indication of learning → assess performance at the beginning of a practice session to assess how much has been retained (learnt) from the last session - Performance plateaus are normal and common → learning still does occur during these times so it is important to provide encouragement so the learner continues to practice Motor Control Theories Learning Outcomes - Discuss the relevance of motor control theory. - Define coordination and the degrees of freedom problem in motor skills. - Compare open-loop and closed-loop control systems. - Differentiate motor program–based and dynamical systems theories. - Define a generalised motor program and its features. - Explain key terms in dynamical systems theory Theory of Motor Control - Theories help us: - Describe a large class of observations - How the nervous system produces coordinated movements - Make predictions about future results - The outcome of these coordinated movements - Why do we care about theories of motor control  - Two major theories are motor program-based theory and dynamical systems theory Coordination - The patterning of head, body, and/or limb motions relative to the patterning of environmental objects and events Degrees of Freedom - Definition – the number of independent components in a system where each component can vary independently - Example – elbow joint has two degrees of freedom: flexion and extension → moves in those 2 ways - The Problem – how can an efficient control system manage a complex system with many degrees of freedom Understanding the degrees of Freedom Problem - How do we control and coordinate our body to accurately perform complex motor skills? Open and Closed Loop Control Closed Loop Control - Involves sensory feedback for movement correction - Updates movement instructions based on feedback - E.g. walking on unstable surfaces - E.g. driving a car Open Loop Control - Lacks sensory feedback - Executed quickly - Updates movement instructions based on feedback - E.g. throwing a dart Two Theories of Motor Control Motor Program Based Theory Schmidt’s Generalised Motor Program - A motor program that controls a class of actions (different actions with a common set of features)  - Parameters must be added to the invariant features in order to meet specific movement demands of a situation Schmidt’s Schema Theory - A rule or set of rules that serves to provide the basis for a decision Schmidt’s Generalised Motor Program - How does motor program-based theory deal with: →Open/Closed Loop control - Initiation is an open-loop control process, but performance can be altered during execution of time is available →Degrees of Freedom - GMP and motor response schema are very abstract/general in nature, and therefore very adaptable Dynamical Systems Theory - Body is a complex system that ‘self-organises’ into coordination patterns, based on constraints - These 3 states are: nonlinear dynamics, self-organisation and attractor states Non-Linear Behaviour Self Organisation - The emergence of a specific stable pattern of behaviour due to certain conditions characterising a situation rather than to a specific control mechanism organising the behaviour Stability and Attractors Dynamical Systems Theory - How does dynamical systems theory deal with: →Open/Closed Loop Control - Large emphasis on interaction with the environment and therefore closed-loop control  - If there is not sufficient time for feedback to be useful, then open-loop control occurs →Degrees Of Freedom - Coordinative structures (muscle synergies) - Functionally specific collections of muscles and joints that act cooperatively to produce an action (e.g. locomotor synergy) - CNS controls synergies, not independent joints and muscles Two Theories of Motor Control Conclusions - Motor Control Theory explains how the body organises movement, helping practitioners create effective motor skill instruction  - Schmidt’s schema theory posits that a generalised motor program stores movement patterns, with specific parameters adjusted for each action - Dynamical systems theory emphasises self-organisation, where movement arises from the dynamic interaction between the body, environment and task Week 2 Neuromotor Basis for Motor Control Basics of the Nervous System The Nervous System - The central nervous system (CNS) is made up of the brain and spinal cord - The CNS controls regulation of body systems and the processing and creation of memories - The peripheral nervous system (PNS) is made up of all neurons connecting the CNS to the rest of the body - The PNS sends messages from the body to the spinal cord and/or brain and back The Neuron →Cell Body (Soma) - The control center of the neuron, containing the nucleus and organelles essential for cellular function →Dendrites - Branching structures that receive signals from other neurons, integrating information for processing →Axon - The long projection that conducts electrical impulses away from the cell body to target cells →Synapse - The junction where neurons communicate, facilitating signal transmission through neurotransmitters Neuron Structure and Function →Myelin sheath - A protective covering called the myelin sheath surrounds all the dendrites and the axon → the myelin sheath is a fatty layer that acts as a layer of insulation →Neurilemma - The nerve cells of the PNS have another protective covering on top of the myelin sheath → this layer called the neurilemma is made up on living cells Types of Neurons →Sensory Neurons - Transmit information from sensory receptors to the central nervous system - They detect external stimuli and proprioceptive feedback →Motor Neurons - Carry commands from the CNS to muscles - Alpha motor neurons directly innervate skeletal muscle fibers →Interneurons - Form complex networks within the CNS - They integrate sensory input and motor output, crucial for reflex arcs Action Potential - Neurons send information through electrical impulses that travel along the axon - Resting state - Depolarisation and repolarisation - Hyperpolarisation and refractory period Neuronal Communication →Signal Transmission - Neurons form pathways that relay information from the sensory organs to the brain or spinal cord →Synaptic Gap - Between the dendrites of one neuron and the axon of another neuron is a small gap called the synaptic gap →Chemical Signal - When a nerve cell is activated, the signal passes through the cell as an electrical signal - Once the electrical signal arrives at the axon, it turns into a chemical signal so it can pass through the synaptic gap and into the next neuron Central Nervous System Anatomy of the CNS →Central Control Center - The brain is the central control center for the body → every bodily function is controlled by the brain →Conscious and Unconscious Control - Some functions are controlled consciously, such as bending your arms → others are unconscious such as breathing or blinking →Connection to the Body - The brain is part of the central nervous system and is connected with the rest of the body by nerves that run along the spinal cord Structure of the Brain - Neurons - Glial cells - Brainstem - Cerebellum - Cerebrum Function of Brainstem, Cerebellum and Cerebrum →Brainstem - The brainstem controls basic functions like breathing, swallowing, blinking and vomiting →Cerebellum - Controls muscle movements, maintains posture and balance →Cerebrum - Largest part of the brain and controls higher thought processes Cerebrum →Frontal Lobe - Responsible for executive functions such as planning, decision-making and personality - Controls voluntary movements and speech →Parietal Lobe - Processes sensory information including touch, temperature, pain and pressure - Aids in spatial awareness and navigation →Temporal Lobe - Processing auditory information, language comprehension and memory - Plays a role in emotion and recognition →Occipital Lobe - Processing visual information - It receives signals from the eyes and interprets them to create our perception of the world The Basic Ganglia - Movement initiation and planning - Control of muscle force and tone - Coordination between antagonistic muscles The Cerebellum - The little brain - Coordination of movements - Error detection - Hand-eye coordination - Timing and posture control - Motor learning The Brainstem - Basic life functions - Motor pathways - Pons - Medulla Oblongata - Reticular Formation Structure and Function of the Spinal Cord →Grey Matter - The grey matter of the spinal cord is located in the center and contains neuron cell bodies, dendrites and synapses - It is responsible for processing and integrating information →White Matter - The white matter, surrounding the grey matter is composed of myelinated axons that carry signals between the brain and the body - It allows for the transmission of information along the spinal cord →Spinal Nerves - Spinal nerves branch out from the spinal cord, carrying sensory information to the brain and motor commands from the brain to muscles and glands - There are 31 pairs of spinal nerves, each serving a specific region of the body →Dorsal Horns - Process sensory information →Ventral Horns - Terminate on skeletal muscles to control movement Tracts →Motor and Descending (efferent) pathways (red) - Pyrimadal tracts →lateral corticospinal tract and anterior corticospinal tract - Extrapyramidal tracts → rubrospinal tract, reticulospinal tracts, olivospinal tract, vestibulospinal tract →Sensory and Ascending (afferent) pathways (blue) - Dorsal Column Medial Lemniscus System → gracile fasciculus and cuneate fasciculus - Spinalcerebellar Tracts → Posterior and Anterior spinocerebellar tract - Anterolateral System → Lateral and Anterior spinothalamic tract - Spino-olivary fibres Ascending Tracts →Dorsal Column - Transmits proprioception, touch and pressure information to the brain →Anterolateral System - Carries pain, temperature, and some touch and pressure signals →Spinocerebellar Tracts - Relay proprioception information directly to the cerebellum for movement coordination Descending Tracts Sensory and Motor Pathways Conclusions - Primary motor cortex controls voluntary movements and fine motor skills - Cerebellum coordinates movement, balance and timing - Basal ganglia regulates movement initiation, muscle tone and posture - Ascending tracts carry sensory information like proprioception, touch and pain to the brain - Descending tracts control fine motor skills, posture and muscloe tone, with pyramidal fibers crossing in the brainstem Integrative Movement Control Motor Units - Alpha motor neuron - Skeletal muscle fibers - Serves as the fundamental unit of motor control in the human body Neuromuscular Junction →Connection Point - The neuromuscular junction links alpha motor neurons to muscle fibers →Signal Transmission - Nerve impulses are transmitted across this specialised synapse →Muscle Response - The transmitted signal triggers muscle fiber contraction Motor Unit Composition and Variability →Fine Movements - Eye muscles have fewer fibers per motor unit, sometimes just one → this allows for more precise control →Gross Movements - Larger muscles can have up to 700 fibers per motor unit → this enables powerful contractions →Adaptability - The variable composition of motor units allows for a wide range of movement types Motor Unit Recruitment →Initial Recruitment - Smallest, weakest motor units are activated first →Progressive Activation - Larger, stronger units are recruited as more force is needed →Full recruitment - Maximum force is achieved when all available motor units are activated Voluntary Movement →Situational Analysis - The brain assesses the situation and individual needs →Movement Intention - A cognitively derived intent for movement is formed →Action Plan - The brain generates a detailed plan for executing the movement Controlling Voluntary Movement Conclusions - The motor unit is fundamental in translating neural signals into muscular movement, forming the basis for motor control - The size principle of motor unit recruitment ensures smooth, efficient force production - The cognitive intent behind movement influences how the brain organises motor activity Week 3 Sensory Components of Motor Control Touch and Proprioception Neural Basis of Touch →Mechanoreceptors - Provide the CNS with information on pain, temperature and movement The Role of Tactile Sensory Information in Motor Control - Movement accuracy - Movement consistency - Movement timing - Movement force adjustments - Estimate movement distance →Movement Accuracy - Tactile feedback significantly influences the accuracy of fine motor skills →Movement Consistency →Movement Timing →Movement Force Adjustments →Estimate Movement Distance Proprioception - Limb Position - Movement Direction - Movement Velocity - Muscle Activation Neural Basis of Proprioception →Muscle Spindles - Detect changes in muscle length →Golgi Tendon Organs - Sense muscle tension, acting as a protective mechanism to prevent injury Neural Basis of Proprioception →Joint Receptors - Detect joint position and motion Coordination Control - Postural Control →Spatial-Temporal Coupling Between Limbs and Limb Segments - Bimanual Coordination - Intra-limb Coordination Conclusions →Touch - Uses mechanoreceptors in the skin to provide sensory information for movement accuracy, consistency, force adjustments, and aiding proprioception in estimating movement distance →Proprioception - Is detected by muscle spindles (limb position and velocity), Golgi-tendon organs (muscle force) and joint receptors (extreme joint movements) Points for the Practitioner - Touch and proprioception are crucial for everyday activities and deficits in these sensory systems can lead to movement accuracy and coordination problems - Identifying such deficits can help explain difficulties a person may have in performing certain tasks Vision Anatomy of the Eye - Cornea: Transparent, dome shaped front part that helps focus light - Pupil: Central opening that adjusts size to control light entry - Iris: Surrounds the pupil, controls its size and gives eye colour - Lens: Flexible, adjusts shape to focus light onto the retina for clear vision Neural Components of Vision →Image processing Visual Pathway to the Brain →Movement Accuracy - Tactile feedback significantly influences the accuracy of fine motor skills Central vs Peripheral Vision →Central Vision - Middle 2 to 5 degrees of the visual field, - Object size, shape and distance - Walking path →Peripheral Vision - Limb movement - Spacial features Monocular vs Binocular Vision Central vs Peripheral Vision Two Visual Systems for Motor Control Perception-Action Coupling - ‘We perceive in order to act and we act in order to perceive’ Time needed for Vision-Based Movement - The minimum time required to process visual feedback and make corrections is between 100-160 milliseconds The Optical Variable Tau - Measures the rate of an object’s image expansion on the retina - Predicts when to act without needing speed or distance calculations Conclusions - The retina is where light is converted into neural signals - Central and peripheral vision work together to process detailed and broad visual information - Visual feedback allows movement corrections within 100-160ms, ensuring accuracy and coordination in real-time tasks Points for the Practitioner - Beginners often rely on vision to compensate for touch and proprioception deficits - Ensure a person’s gaze is focused on the target object for successful action completion - Movement corrections depend on having enough time → fast environments or actions may prevent timely corrections, leading to errors Catching, Striking and Locomotion Fundamental Movement Skills - Body management skills - Locomotor Skills - Object Control Skills Catching - Trajectory - Speed - Timing Phases of Catching Vision of the Object and Catching Tau and Catching - Initial Body Positioning - Grasping Vision of the Hands and Catching Striking - Similar to catching Phases of Striking - Preparation - Execution - Follow through Vision and Striking in Sport - Early vision is important - Perception-action coupling Locomotion - Fundamental skill for daily activity The Rhythmic Structure of Locomotion →Central Pattern Generators: - Groups of nerves in the spinal cord that create basic rhythms for movements - Adapt our walking and running patterns based on how fast we’re moving Head Stability and Locomotion - Visual stability - Balance and coordination Dynamical Systems Theory and Gait - Explains movement coordination - Allows adaptability Vision and Locomotion Avoiding Obstacles →Size and Shape - Help judge the space needed to avoid obstacles based on their size and shape →Distance and Position - Estimates the distance and position of obstacles to plan movement →Predictive Adjustments Conclusion - Successful catching and striking rely heavily on the ability to link visual information with motor responses - Locomotion is controlled by rhythmic patterns from central neural circuits, adapting to changes in speed, terrain and environmental demands - Vision plays a crucial role in guiding locomotion Points for the Practitioner - Emphasise maintaining visual contact with the object before and during its flight - For locomotion, monitor the rhythmic arm-leg relationship and ensure head stability - Encourage visual contact with objects that need to be stepped on or avoided Week 4 Memory and Attention Characteristics of Functional Skills Attention Attention - The cognitive process of selectively focusing on specific information while ignoring other stimuli Characteristics of Attention →Limited Capacity - We can only process a limited amount of information at one time →Selective - We choose which information to focus on based on relevance →Divisible - Attention can be split between multiple tasks, though performance may suffer Theories of Attention Bottleneck Theory - Only handling a certain amount of information creates ‘bottleneck - Lets through things that are prioritised ánd ignores other things - Motor skills → too many stimuli, forced to prioritise some and ignore others Central Resource Theories →Single Resource Pool - Attentional resources drawn from one pool →Capacity Limit - Total capacity is fixed and limited →Resource Allocation - Distributing resources for multiple tasks Kahneman’s Attention Theory - Attention is allocated based on perceived task demands - The availability of resources influences - Resource capacity is determined by both the task demands Role of Arousal - Physiological and Psychological alertness - Influences breath and focus - Optimal levels vary for different tasks - Optimal performance at moderate arousal Multiple Resource Theories →Separate Resources - Attention divided into specialised pools →Task Types - Resources allocated based on task type →Implication - Complex tasks can be managed simultaneously Rules for Allocating Attention →Task Demands - Complexity and Urgency →Resource Availability - Limited mental resources →Practice and Expertise - Automaticity with practice Dual-Task Procedures - Simultaneous Execution of two separate tasks - Primary Task = the task being assessed for attentional demands - Secondary Task = additional task to cause interference - e.g. engaging in mental work reduces force production on hand grip dynamometer Internal vs External Focus of Attention →Internal Focus - Attention on internal processes - Focus on body movements - E.g. muscle tension, technique →External Focus - Attention on external effects - Focus on movement outcome - E.g. target, environment, impact →Participants - 120 undergraduates →Procedures - 5 standing broad jumps - 2-min seated rest between jumps →Groups - External Focus: focus on jumping as far past start line as possible - Internal Focus: focus on extending your knees as rapidly as possible Broad and Narrow Attention →Broad Focus - Attending to a wide range of information →Narrow Focus - Concentrating on a specific detail Automaticity - Tasks performed with minimal conscious effort - Frees up cognitive resources for other tasks - Achieved through extensive practice and repetition Selective Attention →Filtering - Focus on relevant stimuli →Motor Skills - Helps focus on cues for execution →Visual Cues - Identify and respond to environment Quiet Eye - Directed at critical location or object - Stable fixation that begins just before the first movement - Elite performers show longer Quiet Eye durations Conclusions - People have limited availability of mental resources for performing multiple activities simultaneously - Kahneman’s Attention theory proposes a single pool of mental resources that can be flexibly allocated based on arousal levels and task demands - Multiple-resource theories suggest several different resource pools specific to components of skill performance - Visual Selective Attention is critical for preparing to perform a motor skill by focusing on relevant environmental information Practical Implications - Design instruction and practice based on the varying ability to perform multiple activities simultaneously - Be aware of and minimise unusual events in the performance environment to reduce distractions - Ensure skilled individuals maintain optimal arousal or anxiety levels for best performance - Encourage focusing on the intended outcome of the movement rather than the movement itself Memory and Forgetting Memory - Ability to retain information - More than just remembering facts or events Memory Models Working Memory →Temporary Storage - Holds info for immediate task →Processing Hub - Integrates sensory and long-term memory →Multiple Components - Phonological, visuospatial and central executive →Real-Time Decision - Supports processing and decision-making Working Memory Capacity →Limited Capacity - We can remember 7 ± 2 pieces of information →Limited Duration - Information fades after 20-30 seconds without rehearsal →Primacy - Tendency to remember information presented first →Recency - Tendency to remember information presented last - Instructors of movement skills should consider the sequence of skills practiced, placing more challenging skills first or last in a session Long Term Memory - Theoretically unlimited - Information can be stored for long periods, but retrieving it can sometimes be difficult Declarative vs Procedural Knowledge →Declarative - Knowing what →Procedural - Knowing how Procedural Memory →Implicit Memory - Learned through practice and repetition - Stored in procedural memory →Automatic Execution - Allows you to focus on other aspects of performance - E.g. driving a car Semantic and Episodic Memory →Semantic Memory - General knowledge (e.g. facts of the world) →Episodic Memory - Personal experiences Forgetting →Encoding Failure - Information not well-encoded →Interference - Old information disrupts new information →Lack of Practice - Neural connections weaken over time →Proactive Interference - Previously learned material disrupts new learning Assessing Remembering and Forgetting →Explicit Memory Tests - Require conscious recall →Recall Tests - Retrieve information without cues →Recognition Tests - Provide cues to choose the correct option Interference →Proactive - Old memories disrupt new memories →Retroactive - New memories disrupt old memories Organising Memory - Chunking - Assign meaning Context and Memory - A mismatch between practice and test environments can impair recall - Environmental conditions (e.g. lighting, noise) - Personal factors (e.g. mood, sensory feedback) Conclusions - Memory has two main systems: Working Memory and Long-Term Memory - Working memory temporarily stores and manipulates information - Long-Term memory stores information permanently - Forgetting occurs due to trace decay and interference Practical Implications - Keep the time between instructions and practice short and free of other activities - Avoid describing ‘what not to do’ before or after instructions; if needed, do so after practice - Practice in environments similar to real-world situations to improve retention and performance Functional Skills Speed-Accuracy Trade-off - Manual aiming skills involve accurate movement to a target - Increasing speed reduces accuracy → and vice versa Fitt’s Law - Fitt’s Law models the relationship between movement time, target size and distance Applying Fitt’s Law - Larger targets allow faster movements - Fitt’s Law informs interface design Phases in Speed-Accuracy Tasks 1. Preparation - Brain gathers information about the task 2. Initial Flight - Open-loop control, pre-programmed movement 3. Termination - Closed loop control, fine adjustments using feedback Vision in Speed-Accuracy Tasks →Planning - Vision helps analyse task and environment →Execution - Visual feedback critical for final corrections →Adjustment - Vision aids in judging distances and speeds Importance of Instruction Prehension and Handwriting Prehension →Reach and Grasp - Action of reaching for and grasping objects →Sensory Integration - Vision, proprioception, motor planning →Components of Prehension - Transport, grasp, object manipulation →Context-Dependant - Object properties, intended action Components of Prehension →Transport - Arm movement brings hand to object →Grasp - Hand shapes itself in response to object →Manipulation - Object use depends on functional goal Temporal Coupling in Prehension Prehension and Fitt’s Law - Grasping small objects or distant objects takes longer Handwriting - Complex motor control - Adapting the size, force and direction of strokes Cognitive and Motor Processes - Adapt the movement while maintaining consistency in the output - Cognitive and motor processes Vision and Handwriting Bimanual Coordination Symmetric vs Asymmetric Bimanual Coordination →Symmetric - Same movement with both arms e.g. rowing →Asymmetric - Different movement with each arm e.g. playing guitar Challenges in Asymmetric Coordination - Brain prefers symmetry in movement - Harder to coordinate different tasks for each limb Motor Control and Theories →Generalised Motor Program - Single program for symmetric, seperate/adapted programs for asymmetric tasks →Dynamical Systems Theory - Symmetric movements are natural ‘attractor states’ The Role of Feedback →Proprioceptive Feedback - Helps control limb position and movement →Visual Feedback - Critical in learning asymmetric coordination Conclusions - The speed at which a skill is performed is influenced by movement and accuracy demands - Prehension involves the synergy between transport, grasp and object manipulation - Bimanual coordination has a preference for symmetry Points for the Practitioner - When teaching speed-accuracy skills, prioritise accuracy over speed initially - Incorporate visual feedback strategies to enhance grasp accuracy and transport efficiency - Begin with simple, symmetric tasks and gradually introduce more complex, asymmetric movements Week 5 Traditional Theories of Motor Learning and Skill Acquisition Intro to Motor Learning →Learning - A change in a person’s ability to perform a skill, inferred from a lasting improvement due to practice or experience  - 1. Improvement - 2. Consistency - 3. Stability - 4. Persistence - 5. Adaptability Association Theories →Stimulus Identification - Interpreting sensory information →Response Selection - Deciding on the action to take →Response Programming - Translating the decision into motor commands Stages of Learning Information Processing Theories →Stimulus Identification - Interpreting sensory information →Response Selection - Deciding on the action to take →Response programming - Translating the decision into motor commands Open and Closed Loop Control Limitations of Information Processing Theories Neurocomputational Theories - Optimised to achieve specific behavioural goals - Balance between task performance, stability and energy efficiency - Brain refines movements to be more efficient The Role of Internal Models →Forward Model - Predicts sensory consequences of actions →Inverse Model - Maps desired outcomes to motor commands Brain Areas Involved →Primary Motor Cortex - Executes voluntary movements →Cerebellum - Fine-tunes movements →Basal Ganglia - Automates routine movements →Prefrontal Cortex - Planning and decision-making Challenges of Neurocomputational Models - Complexities in multi-limb coordination - Translating spatial representations into muscle commands - Real-time communication between brain regions Comparing Traditional Theories Criticisms and Limitations of Traditional Theories →Overemphasis on Internal Representations - Internal models are important but don’t capture the full picture →Lack of Emphasis on Body Environment Interactions - Movement is shaped by sensory feedback from the surroundings →Simplified View of Movement Dynamics - Real movement is more dynamic and flexible Conclusions - Information processing theories treat skill acquisition as sequential steps where the brain processes input and selects responses - Neurocomputational Theories emphasise neural networks in the brain that encode and adapt movement patterns through practice - Traditional theories often focus too much on internal processes, ignoring the interaction between learner and environment Constraints on Motor Performance Dynamical Systems Theory Recap →Complex System - Motor performance as intricate, dynamic process →Constraint Interaction - Movement arises from interplay of various factors →Self-Organisation - Patterns emerge from environment, individual, task demands Ecological Dynamics Understanding Constraints - Factors limiting or shaping motor task performance - Crucial for effective motor performance analysis Individual Constraints →Physical - Strength, flexibility, coordination, injury status →Cognitive - Decision-making, attentional focus, perception Task Constraints →Rules - Specific requirements and objectives of activity →Equipment - Size, weight, design of tools used →Strategy - Tactical approaches influenced by task demands Environmental Constraints →External Factors - Weather, surface type, spatial dimensions →Social Dynamics - Team interactions, audience presence →Cultural Context - Societal norms influencing performance expectations Interaction of Constraints →Continuous Interplay - Constraints interact dynamically during performance →Adaptive Responses - Athletes adjust to changing constraint interactions →Performance Variability - Outcomes influenced by complex constraint interactions Research on Constraints - Constraints impact performance - Examined motor performance participants with and without MS under different task constraints - MS participants performed tasks slower due to reduced action capabilities, highlighting the importance of understanding constraints Importance of Context - Motor performance varies with different environments, affecting outcomes - Training in varied scenarios builds adaptability - Practice in varied settings to prepare for diverse performance conditions Conclusions - Ecological dynamics focuses on the interaction between individuals and their environment to shape learning - Constraints shape motor performance through interaction of individual, task, and environmental factors - Constraints are continuously interacting A Constraints Led Approach to Motor Learning Ecological Dynamics →Dynamical Systems Theory - Movement emerges from fluid interactions of various systems →Ecological Psychology - Effective movement arises from perceiving affordances →Holistic Perspective - Motor learning is adaptive and influenced by context Constraints-Led Approach Overview Perceptual-Action Coupling - The ongoing relationship between what a learner senses and how they move - Practice environments should mirror the perceptual and decision-making demands of real performance Perceptual-Motor Landscape →Attractors - Stable movement patterns that satisfy task goals →Landscape Shifts - Changes in constraints lead to new attractors →Exploration - Learners discover effective coordination through practice →Adaptability - Richer landscape allows better performance across contexts Affordances - Opportunities for action - Unique to each individual Movement Variability - Supports exploration and adaptability - Enables learners to respond to changing constraints - Builds diverse set of movement solutions - Promotes creativity and innovation in movement Facilitating Learning →Modifying Constraints - Adapt task, environment, and performer to create new challenges →Encouraging Exploration - Design open-ended tasks and scenarios for problem-solving →Minimising Direct Feedback - Promote self-reflection and self-assessment through guiding questions →Creating Diverse Environments - Introduce variability to enhance adaptability and transfer Hands-Off Practitioner →Observation - Closely monitor learners to identify emerging patterns →Questioning - Prompt critical thinking through strategic questioning →Feedback - Provide information, non-prescriptive feedback to guide learning →Constraints - Manipulate task, environment and organism constraints to provoke exploration Retention and Transfer →Increased Skill Retention - Practitioners can utilise the Constraints-Led Approach to improve learner’s ability to maintain skills over time →Enhanced Skill Transfer - The Constraints-Led Approach helps learners apply skills effectively in various contexts, fostering adaptability Technique Change 1. Identify current constraints 2. Define desired outcomes 3. Manipulate task constraints 4. Encourage exploration 5. Provide supportive feedback CLA In Practice Multidisciplinary Approach →Biomechanics - Understanding the mechanical aspects of movement →Physiology - Examining the bodily systems involved in movement →Psychology - Exploring cognitive and emotional factors →Sociology - Considering the social and cultural influences Conclusions - Nonlinear Pedagogy and Constraints-Led learning emphasise adaptability, variability and learner-environment interaction - Role of variability is essential for exploration and adaptation, helping learners find effective movement solutions - Integrating insights from various disciplines leads to a more comprehensive and effective understanding of motor skill acquisition Implications for Practice - Encourage variability in practice to foster adaptability - Minimise direct instructions and focus on facilitative feedback - Facilitate technique changes through constraint manipulation Week 7 Verbal Instruction and Cues in Motor Learning What is Instruction? - Adequate and effective learning of motor skills often involves formal instruction: - Verbal instructions - Verbal cues - Styles of instruction and demonstration should be based in sound theory and reliable empirical evidence - Skill practice where instruction and demonstration are absent is often ineffective and inefficient Purpose of Verbal Instruction →Effective verbal instruction can provide the following benefits to the learner - Understanding of performance requirements (critical features) and goals - Provide structure and direction to practice sessions - Enhance learner confidence - Reinforce correct behaviours  - Emphasise relevance of skill/movement being instructed - Promote skill learning →To be effective, instructions need to be tailored to the learner and his or her specific needs in their specific situation →Knowledgeable instructors recognise the needs of learners at various stages of skill development Characteristics of Verbal Instruction - Verbal instruction involves telling the learner what to think about and what to do before they attempt to practice the skill →Several factors are particularly important for developing effective verbal instruction - Content of verbal instruction (critical features) - Quantity of verbal instruction - Precision of verbal instruction - Focus of verbal instruction Verbal Cues - Verbal instructions can contain too little or too much information, and not provide the learner with necessary information to achieve the goal of the skill →Verbal cues are short, concise phrases that serve to: - (1) Direct the performers attention to regulatory conditions in the environmental context - (2) Prompt key movement component of skills →Examples - The cue “look at the ball” directs visual attention - The cue “bend your knee” prompts an essential movement component →Simple cueing statements can be very effective as verbal instructions to facilitate learning new skills, as well as performing well-learned skills Content of Verbal Instruction - Content of instruction refers to “what” you say i.e. what do you want the learner to focus on or think about while attempting the movement? - Focus verbal instructions on those features of a skill that are most critical to performance and learning i.e. critical features - Instructor must understand and analyse the movement themselves so that their verbal instruction - Correct identification of critical features is crucial for developing content of verbal instruction - Take advantage of the skills that a learner already knows when formulating verbal instructions for a new skill Precision of Verbal Instruction - Descriptions that may seem clear to instructors because of their experience with a skill can be confusing to beginners - When providing instructions, instructors should focus on providing meaningful descriptions - E.g. “rotate your hips 45 degrees” vs “rotate your hips more” - Effective instructions do not allow for varying interpretations - Becomes familiar with the level of precision that works most effectively for specific individuals - Research indicates that beginner learners respond better to more general, rather than specific, instructions Quantity of Verbal Instruction - Humans have a limited attentional capacity for the amount of information that can be held and acted upon in short-term memory →The amount of information provided in verbal instruction should be in accordance with: - Learner’s developmental limitations and needs - Learner’s attentional capacity Focus of Verbal Instruction - A key part of skill learning is where a person directs conscious attention when performing a skill - In performing any skill two distinct processes can be identified: - Perceptual processes (ascending neural pathways) - the performer must perceive what is in the environment (sensory information about external conditions) → event code - Action Processes (descending neural pathways) - based upon perceptual information a person decides upon, organises and initiates a motor response → action code - All voluntary motor behaviour is a combination of event codes and action codes Focus on Verbal Instruction - An essential role of movement instructors is to promote the learning of the mental operations responsible for translation into physical acts, i.e. what is the appropriate physical response to a specific situation? - Common Coding Approach (Prinz, 1997) - a functional relationship between perception and action - Perceived events and planned actions share a common representational domain - i.e. direct communication is possible between areas within the brain that process actions and effects - Execution of bodily movements (actions) are always coupled to representations of their effects - Actions will be more effective when a person focuses their attention on the intended outcomes of an action, rather than on the movements required by the skill  - Internal focus of attention - instructions which focus learner’s attention on the actual movement pattern involved in producing the skill - External focus of attention - instructions which focus learners’ attention to the effects of their movements Focus of Verbal Instruction Case Study - Wulf et al. (1998) - Novice subjects - Slalom-ski instructor - Goal - “Continuously move the platform for 90 seconds as far as possible to the left and right qat a rate of one complete cycle every 2 seconds” - Group 1 - “concentrate on the force exerted on the wheels on the platform directly under the feet (external focus) - Group 2 - “focus attention on force exerted by outer foot in moving the platform (internal focus) - Group 3 - control group , i.e. no instruction provided for focus of attention - Instructions that promote an external focus of attention lead to better learning than instructions with an internal focus Providing Effective Verbal Instruction →Summary of important points for providing effective verbal instruction - Highlight important critical features - Provide a limited number (three maximum) critical features on which to focus attention - Instruction should be as precise and succinct as possible (remove room for varying interpretations of instruction) - Direct learner’s attention to movement outcomes (external focus) rather than body movements (internal focus) - Where possible take advantage of learner’s existing skills - Be aware of learner’s attentional capacity, and modify instructions accordingly - repeat/reiterate/summarise the few most important critical features immediately before learner’s practice attempt Observational Learning and Demonstration Observational Learning - Observational learning is “any instance where one observes someone, and, based on this observation, learns something new or modifies a previously learned skill or behaviour” (Ramsey et al., 2021)  - “Learning” here is defined as an enduring change in the way that an organism responds, based on its experiences - In this course, we focus on subtype of observational learning that has two necessary requirements: - A physical action or movement must be observed - An enduring change to motor performance must occur Components of Observational Learning - According to social learning theory, observational learning influences the acquisition of a motor skill through four subprocesses, i.e. four sequential and interrelated parameters (Bandurra 1977) - 1. Attention - the behaviours to which the learner must pay attention when observing. determines what type of demonstration prototype to select → plays crucial role in acquisition phase - 2. Retention - the observed behaviours are stored in the memory in the form of symbols through schemata and verbalisation → plays a crucial role in acquisition phase - 3. Reproduction - the stored information or observed and learned behaviours are reproduced → plays a crucial role in executing the motor skill - 4. Motivation - the demonstrative behaviour that learners show under certain situational conditions → plays a crucial role in executing the motor skill Effectiveness of Observational Learning - Research indicates that observational learning is more effective than the absence of observational learning in promoting motor skill learning  - Bazzini et al. (2022) - Methods - AOT = Action Observation Training - alternated between observational learning and physical practice - OL = Observational Learning - initial observation, one physical practice, then all observation learning - MP = Motor Practice - initial observation, then all physical practice Action Observation Training - Research shows that observational learning interspersed with physical practice is more effective than physical practice only or observatoinal learning only for motor skill learning - The process of alternating observational learning with physical practice is labelled as “Action Observation Training (AOT)” - Action Observation Training has the potential to combine the advantages of motor practice and observational learning, which has a higher effect than the sum of that achieved by observational learning and physical practice (Bazzini et al., 2022) - Action Observation Training constructs a process of cognitive adaptation in motor skill acquisition, whereby movements are organized into cognitive representations and then developed into symbolic codes to guide execution Mechanism of Action Observation Training - Action observation training activates the cortical motor system, tuning the formation of new motor programs - Regular alternation between observation and execution activates the motor system according to the correct motor program, so the person then executes the action with a motor system already pre-activated and geared toward a correct performance (Bazziini 2022) Purpose of Demonstration - Most frequently used method of conveying information to learners - Should not replace, but rather ‘complement’ verbal instructions - Can convey information concerning complex movement patterns that would be impossible to communicate verbally “a picture is worth a thousand words” Priming Learners Through Demonstrations - “Priming” = introduction of new information or skill before practice - “Priming” = a brief physical demonstration of the whole skill in real-time without concurrent verbal instruction before practice - Gives learners an idea of what they are going to practice - Providing a “priming” demonstration without concurrent verbal instructions allows learners to make better use of subsequent verbal instruction Demonstration - Optimal Viewing Perspectives - It is important to ensure that demonstrations are provided to the learner from an appropriate perspective, this could mean demonstration from more than one view - Ensure that you fully understand the critical features of the skill/exercise and that you know the most suitable perspective for the learner to view this from - Think about whether it is best for you as demonstrator to move to change the learner’s viewing perspective, or if its better for the learner to move to achieve the optimal viewing perspective Mirror Neurons - A special class of visuomotor neurons in the brain - mirror neurons - identified in 1992 - Fires in two different circumstances: - When performing a given motor act - When observing the same or a similar act being performed - A study was carried out on two rhesus macaque monkeys → the monkeys were trained to perform two actions with different - Some of the 15 motor neurons had mirror properties and selectively discharged during the observation of motor acts when these were embedded in a given action (e.g. grasping-for-eating but not grasping-for-placing) - Activation of mirror neurons give information not only on what but also on why grasping is done (grasping-for-eating) - This specificity allowed the observer not only to recognise the observed motor act, but also to understand the intentions of the action’s agent Mirror Neurons - Human brain has multiple systems of mirror neurons - Motor and social behaviours (e.g. language, understanding intention) - Mirror neurons in the pre-motor cortex become excited when observing a movement or skill in which the observer has some experience - Mirror neurons in the pre-motor cortex do not become excited when observing a mnovement or skill in which the observer does not have experience - It is believed that mirror neurons are responsible for planning and initiation of voluntary movements, though not the actual execution of movement - Observing a motor act activates the same motor network required by the observer to execute that action themselves - Human infant data using the eye-tracking measures suggest that the mirror neuron system develops before 12 months of age Providing Effective Demonstration of Skills →Summary of important points for providing effective demonstration of motor skills - Provide demonstrations before initial practice (priming) and spaced throughout session - Provide demonstration from multiple perspectives, as appropriate - The process of observation can be useful for motor learner, especially if the learner has some experience with the skill - The brain can simulate a learned skill simply through observing. So don’t think demonstration is not necessary if the learner already knows the exercise Week 8 Feedback in Motor Learning - Application of Augmented Feedback Guidelines for Providing Feedback - In establishing guidelines for the effective provision of augmented feedback, three important areas must be considered: - 1. The precision of the feedback → general or specific? - 2. The timing of feedback → provided immediately after practice attempt or delayed? - 3. The frequency of feedback → given for all practice attempts or for only a few? Precision of Feedback - Feedback can be classified as either qualitative or quantitative →Qualitative feedback provides information about the direction of an error without reference to the magnitude of the error - “That was faster than last time” - “That was too far for me” - “Bend your knees more” →Quantitative feedback provides information about the direction and magnitude of an error - “That was 2 seconds faster than last time” - “That was 10cm too far” - “Bend your knees to 60 degrees” →Quantitative feedback is more precise than qualitative and allows for less ambiguity due to variation in interpretation of information - Learning is enhanced as the precision of feedback increases, but only up to a point - There is a limit to how much precise quantitative feedback can be helpful to a learner, at each stage of learning - Feedback should be provided with only as much precision as a learner can meaningfully interpret and apply →How many errors should be identified in a feedback statement? - Greater precision in feedback is provided when more errors are corrected, but too many corrections provided in one statement can overwhelm learners - Learners, especially beginners, cannot internalise many corrections at one time - Skilled movement instructors need to know which corrections are most important for the learner: - One, crucially needed, correction at a time - Two or three crucial corrections in a single practice session Precision of Feedback - Individuals in the early stages of learning can be very uncertain about the meaning of their own sensory feedback - Learners rely heavily on external sources of feedback - Learners have been shown to give greater consideration to external feedback than to their own sensory feedback, even when external feedback is erroneous (i.e. contradicts sensory feedback) - Movement instructors should be very careful and conscientious in providing correct and accurate feedback Timing of Feedback - There are three timing intervals associated with provision of augmented feedback - KR/KP - delay interval – time between completing practice attempt (Response 1) and receiving KR/KP - Post KR/KP-delay interval – time from delivery of KR/KP to starting next practice attempt (Response 2) - Inter-response interval – total time between practice attempts (Response 1 – Response 2) →Factors to Consider - How soon after a practice attempt should feedback be given? - Once learners are provided with feedback, how soon after should they practice the next attempt? - The limited attention span of some learners would suggest that time intervals between practice and feedback should be so short, but is this necessarily the case? - Research suggests that at least a few seconds delay between practice attempt and delivery of feedback maximises learning: - The delay in providing feedback (3-5 seconds) gives the learner time to process their own sensory feedback - After providing feedback, learners need some time (3-5 seconds) to compare sensory and augmented feedback Frequency of Feedback →How frequently does feedback need to be provided for the learner to get the greatest benefit? →Categories of feedback frequency - Absolute frequency of feedback – total number of practice attempts for which feedback is provided - Relative frequency of feedback – proportion of practice attempts for which feedback is provided - Frequent feedback does promote better practice performance, but what about learning? - There is a curvilinear relationship between learning and the relative frequency of feedback - High relative frequencies of feedback depress optimal learning - Below a certain level of frequency, learning is also impeded  - The effect of the frequency of feedback is dependant on the experience of the learner and the complexity of the task Frequency of Feedback - Some explanations for the relative frequency effects: - Guidance hypothesis – reducing the relative frequency of feedback is beneficial because it lessens the temporary and negative effects of guidance - Feedback beocmes part of stimuli associated with the task to be learned – learners cannot perform task without feedback - Learner’s are encouraged to make too many corrections during execution of a task, so they fail to produce a stable and consistent behaviours - Frequent feedback may block or interfere with other important processing functions, e.g. less attention paid to sensory feedback, ability to self-detect errors diminishes Schedules for Fading Feedback →There are several methods for reducing (fading) the relative frequency of feedback: - Summary Feedback - Average Feedback - Bandwidth Feedback - Learner Requested Feedback Fading Feedback – Summary Feedback - Feedback is provided for every attempt but not until after a predetermined number of attempts have been completed - When a task is simple, 15-20 attempts before providing feedback - When a task is complex, less attempts (5-10) before providing feedback - Learner experience also affects the number of attempts before feedback - Instructors can fade feedback by progressively lengthening the summary length Fading Feedback – Average Feedback - A predetermined number of practice attempts are completed before feedback is provided - Feedback is provided as average of all practice attempts - No feedback for individual practice attempts - Provides learners with a general sense of their movement errors Fading Feedback – Bandwidth Feedback - Feedback only provided when a learner’s performance falls outside of a pre-determined acceptable range of correctness, or “bandwidth” - As learners improve the bandwidth narrows - Advantage is that learners determine the frequency of feedback according to their own performance - Only worst attempts receive feedback Fading Feedback – Requested Feedback - Learners receive feedback only when they request - Feedback fading occurs as a natural outcome of a decrease in the learner’s perception of their feedback needs - This method may involve greater attention and problem-solving strategies for the learner → enhanced learning Providing Effective Feedback – Summary - Learning is enhanced as the precision of feedback increases, but only up to a point. There is a limit to how much precise quantitative feedback can be helpful to a learner, at each stage of learning - People in the early stage of learning, give most attention to the most qualitative information, even if quantitative information is also provided. Therefore, in the early stages of learning it may be more beneficial to provide general (qualitative) rather than specific (quantitative) feedback - Learners have been shown to give greater consideration to external feedback than to their own sensory feedback, even when external feedback is erroneous (i.e. contradicts sensory feedback) Movement instructors should therefore be very careful and conscientious in providing correct and accurate feedback Providing Effective Feedback – Summary - At least a few seconds delay between the practice attempt and delivery of feedback maximises learning. The delay in providing feedback (3-5 seconds) gives the learner time to process their own sensory feedback. After providing feedback, learners need some time (3-5 seconds) to compare sensory and augmented feedback - Do not feel compelled to give augmented feedback after every practice attempt. When you do not give augmented feedback, you provide learners the opportunity to determine what their own sensory feedback tells them about their performance - Gradually reduce the amount of feedback provided as the learner improves in the skill. There are various strategies for doing this e.g. summary feedback, bandwidth feedback. Week 9 Practice Variability and Specificity Importance of Practice →Learning Requires Practice - Quality - Time →Practice organisation affects motor skill learning - Rate of learning - Stability of learning - Amount of learning - Movement instructors need to carefully consider how practice is scheduled in order to facilitate optimal learning Practice Variability - Refers to the ‘variety of movement and context characteristics a person experiences while practicing a skill’ - Practice variability can be applied through variations of characteristics of: →Environment/context in which the learner performs the skill - Skill being practiced by the learner →For optimal learning, movement instructors must consider - Type of variation - Amount of variation Practice Variability and Motor Learning Theories - The concept of practice variability can be applied to all theories of motor learning - Schema theory – emphasises that successful future performance depends on the amount of movement variability - Gentile’s model – emphaises the learner’s need to experience variations of regulatory and non-regulatory condition  - Dynamical systems theory – emphasises learner’s need to explore the perceptual motor workspace and discover optimal solutions to the degrees of freedom problem posed by the skill - Practice variability promotes increased capability to not only perform the skill, but also to perform the skill in novel conditions i.e. positive transfer to other conditions Contextual Interference - Interference or variability that results from performing different tasks or skills within the context of a single practice session (Schmidt and Lee, 2005) - ‘Interference’ – memory or performance disruption - Different amounts of contextual interference can result from different practice schedules - Blocked, random and serial practice can be considered to be on a continuum of contextual interference Practice Schedules and Contextual Interference - High contextual interference promotes better motor learning because it demands greater cognitive effort during execution of the motor skill Elaborative – Processing Hypothesis (Shea and Zimny 1983) - Random practice requires a higher level of inter-task comparisons between trials - The learner undergoes further “elaboration” and distinction in memory in random practice than in blocked practice Action Plan Reconstruction Hypothesis (Lee and Magill, 1983) - In each trial (T) the learner forgets the last motor program (MP) in the working memory and retrieves another MP from the long term memory - This action plan reconstruction requires more effortful practice → stronger representation and better retention and transfer Cortical Activation and Excitability Practice Specificity - Practice specificity hypothesis – motor skill learning is influenced by practice condition characteristics - One of the oldest principles of human learning – origins traced back to early 1900s (Thorndike and Woodworth, 1901) - Researchers generally agree there are 3 characteristics to consider to consider in relation to practice specificity - Sensory/perceptual characteristics - Performance context characteristics - Cognitive processing characteristics Sensory/Perceptual Characteristics - Motor skill learning is specific to the sources of sensory/perceptual information available during practice: - Proprioceptive information - Visual information - Visual sensory feedback is important during early learning, but importance diminishes with practice and is replaced by proprioceptive information Performance Context Characteristics - The encoding specificity principle identifies the strong association between encoding and retrieval contexts for memory performance - The more a memory test (i.e. retrieval) context resembles the practice (i.e. encoding) context, the better will be retention performance - People learn more about the context than they are explicitly instructed to learn - Intentional remembering – when you must remember specified characteristics of an environmental context - Incidental remembering – remembering related but non-essential parts of the context Cognitive Processing Characteristics - According to the transfer appropriate processing theory, the type of practice that is best requires the same type of cognitive processing activity required in a transfer test, regardless of the physical similarity between the practice and test situations - Rapid decision making - Selective attention - Dual tasking Practice Variability and Practice Specificity – Summary - Although the practice specificity hypothesis may appear to be at odds with the practice variability hypothesis, research indicates that each hypothesis may pertain to specific aspects of the practice context - Practice variability hypothesis explains the retention and transfer benefit associated with practicing multiple variations of a skill - relates primarily to the movement characteristics of the skill - Practice specificity hypothesis explains why retention and transfer tend to be better when the practice and test contexts are similar - relates primarily to characteristics of the practice and test context Amount and Distribution of Practice Practice Scheduling for Multiple Tasks - There are a few ways to sequence the practice of multiple practice tasks during a practice session →Blocked Practice - All trials of a given task are completed before moving onto the next task - Blocks of skills are practiced in isolation →Serial Practice - Practice trials that are constantly changing, but in a predictable order →Random Practice - Order of task presentation is randomised, so that practice of various tasks is mixed across the practice period - Immediate practice challenge Practice Schedule: Blocked vs Random - Practiced 3 different arm movement tasks: - Group 1 = random practice - Group 2 = blocked practice  - Random group – poorer performance in the acquisition phase - Random group – better performance in retention tests - Retention test evaluates learning → random practice group learnt more effectively than blocked practice group Practice Distribution for a Single Task - Two classes of practice within a single practice session have been defined. These are based on the relative amounts of practice and rest provided - Distributed practice involves much more rest between trials, perhaps with the rest period being as long as the trial itself - Massed practice provides relatively little rest between trials - Distribution of practice between practice sessions also has implications for motor learning Within-Session Practice: Massed or Distributed - Ladder climbing task - Group 1 = Distributed practice - 30 sec rest between practice trials - Group 2 = Massed practice - No rest between practice trials - Fatigue from massed practice reduces performance during initial practice (i.e. during acquisition) but the impact on retention is minimal Between-Session Practice Effects - Practice scheduling question: - Over what length of time should practice be distributed? - Daily? - Every second day? - Weekly? - Is it better to have short sessions frequently or long sessions less often? - Evidence supports distributive practice of many sessions →Practice Implications - Distribute practice experiences as much as possible over many shorter practice sessions - Distributed practice allows more time for memory consolidation - Periods of sleep may be essential for memory consolidation Use of Part Practice - Part practice – reduction of complex skill into component parts - Reduce demand on learners - Provide early success - Part practice does not always lead to the best learning outcomes - Three methods of part practice→ segmentation, simplification and fractionisation Part Practice - Segmentation - Skill broken down into component parts or segments - Divided into different segments each of shorter duration - Each segment is practiced separately - Once a level of proficiency is achieved, parts are put back together Part Practice - Simplification - Simplifying some aspects of practice before adding more difficult components - Aspects of skill can be simplified but still has the same goal - Aspects of environment can be simplified: - Object - Surface - Other people - Important for graded therapeutic exercise prescription and progression Part Practice - Fractionisation - Practicing, usually in isolation, the components of a skill that are usually performed simutaneously - Usually divided into separate use of different body regions - E.g. practice arm movements and leg movements separately then combine together - Concerns about fractionisation - timing and coordination between limbs is crucial to successful performance of skill Summary of Points for the Movement Instructor →Practice Scheduling - Practice schedules that promote variability among practice trials (random) may impair performance during practice, but often enhance long-term retention and learning →Practice Distribution - Within session practice: - For discrete skills, little difference of effect of massed or distributed practice on performance or learning - For continuous and serial skills, strong detrimental effect of massed practice on performance during practice because of fatigue states, but only slight effects on learning - Between session practice: - Distributed practice promotes better learning for all skills →Part Practice - Part practice mauy improve learning during early stages of practice, but task complexity and organisation should be carefully considered Week 10 Changes in Motor Performance and Learning: Aging and Injury Motor Performance: Age and Injury - Motor skills play a crucial role in all phases of the life span - People of all ages perform fundamental motor skills (e.g. waking; grasping), or specific skills (driving a car; hammering a nail) - It is well known that aging is accompanied by impairments in sensorimotor, cognitive and perceptual functioning - When people age, they typically perform complex tasks more slowly and less accurately than they once did - They also begin to carry out tasks in qualitatively different ways Motor Learning: Age and Injury - Motor skill learning is critically important across the lifespan: - Early development - Childhood - Adulthood - Older age - Motor skill learner can be impacted by injury and pathological condititions, and can therefore play a crucial role in rehabilitation processes Grey Matter and White Matter - Central nervous system (CNS) is made up of grey and white matter - Grey matter and white are both essential sections of both the brain and spinal cord - In brain - grey matter is superficial to white matter - In spinal cord - white matter is superficial to grey matter →Grey Matter - Contains the majority of neuron cell bodies, circular structures that house the nucleus of the cells - Grey matter gets its grey tone from its high concentration of neuronal cell bodies - Grey matter enables control of movement, memory, and emotions - Different areas of the brain are responsible for various functions, and grey matter plays a significant role in all aspects of human life →White Matter - Comprises myelinated and unmyelinated axons and glial cells, including myelin-producing oligodendrocytes, microglia, astrocytes and oligodendrocyte progenitor cells - White matter is a network of nerve fibers that allows the exchange of information between different areas of grey matter Effect of Aging on Grey Matter - As people age, they naturally experience a decline in grey matter volume: - Regions affected – grey matter volume decreases in all regions of the brain, but some regions are affected more than others → the precentral gyrus, postcentral gyrus, middle frontal gyrus, and insula are particularly affected - Interaction with gender – the rate at which grey matter volume decreases varies between men and women - Interaction with exercise – people who exercise regularly tend to have more grey volume than people of the same age who don’t exercise - Interaction with learning – learning new skills or information over multiple weeks can help improve grey matter health Effect of Aging on White Matter - Ageing can cause a number of changes to white matter in the brain, including: - Decreased volume: White matter volume increases until about age 45-50, then rapidly decreases after that - Lesions: white matter lesions can appear - Disrupted integrity: white matter integrity can become disrupted - Myelin degradation: Myelin can degrade, including through loss of myelinated fibers and malformation of myelin sheaths - Decreased conduction velocity: Myelin splitting can lead to decreased conduction velocity Ageing and Brain Function - Despite generally having lower grey matter volume than young adults, older adults are found to have heightened brain activity compared to younger adults during performance of motor tasks - This has been interpreted as age related over-activation or hyperactivation - Two primary hypotheses have been proposed in the literature to explain this age-related over-activation: - De-differentiation hypothesis - suggests that aging is associated with a decline in functional specificity of brain activation in response to task demands, resulting in non-selective recruitment of additional brain regions - Compensation Hypothesis - suggests that overactive sites in older adult brains are “working harder” than the corresponding regions in their younger counterparts - Neurotransmitter levels are lower in older adults than young adults and this may impact their modulatory capacity as a function of task training Ageing and Motor Performance - Research Indicated that ageing generally affects motor performance, resulting in slower movements and/or reduced accuracy Neuroplasticity - Neuroplasticity (or brain plasticity) is the “ability of the nervous system to change its activity in response to intrinsic or extrinsic stimuli by reorganising its structure, functions or connections (Mateos-Apariciio et al., 2019) - Neuroplasticity occurs across the lifespan and is required for the maintenance and adaptation of neural connections - Neuroplasticity is crucial for the learning process Mechanisms of Neuroplasticity - Modified gene expression - protein synthesis to facilitate changes in neuronal dendrites and synaptic connectivity - Dendritic remodelling - increased basilar dendrite length, density and complexity - Myelin plasticity - increase in myelin content - Cytogenesis - neuro-, glio- and angiogenesis → neurogenesis occurs in two specific niches of the adult brain, while gliogenesis is ubiquitous. Together these cellular changes contribute to larger grey and white matter volumes - Synaptic strengthening - alterations to myelin ensheathment fine tunes synaptic communication strengthening the function of synaptic junctions - Increased circulating neurotrophins - including brain-derived neurotrophic factor (BDNF), nerve growth factor (NGF), Vascular endothelial growth factor (VEGF), insulin-like growth factor 1 (IGF-1), contribute to several cellular alterations in the brain Ageing, Neuroplasticity and Motor Learning Injury, Neuroplasticity and Motor Learning - The ability of the brain to reorganise its structure and function via neuroplastic mechanisms is an invaluable tool for ameliorating deficits due to condition such as stroke or spinal cord injury, alzheimer’s disease - Neurorehabilitation is based on the assumption that motor learning contributes to motor recovery after injury - Funcitonal recovery can occur through resolution of impairment (reacquisition of premorbid movement patterns) and/or through compensation (use of alternative movements or effectors to accomplish the same goal) - Both resolution of impairment and compensation respond to training protocols - The emphasis in current neurorehabilitation practice is on the rapid establishment of independence in activities of daily living through compensatory strategies, rather than on the reduction of impairment Injury, Neuroplasticity and Motor Learning - Learning is required for both true recovery and compensation → early training appears critical to promoting recovery of impairment and brain reorganisation after injury - Animal models show that after focal ischemic damage there is a brief, approximately 3-4 week, window of heightened plasticity in which combination with training protocols lead to large gains in motor function - Analogously, most recovery from impairment in humans occurs in the first 3 months after stroke, which suggests that targeting impairment in this time-window suggests that targeting impairment in this time-window with intense motor learning protocols could lead to gains in function that are comparable in terms of effect size to those seen in animal models Summary of Key Points - Although older adults typically perform worse on motor tasks than younger adults, they show clear training-induced improvements, though sometimes at a different rate, demonstrating the capacity for motor learning is preserved across the lifespan - In both older and younger adults, motor training-induced performance improvements are linked to inter-individual variations in macro- and microstructural brain characteristics with greater volume (grey matter) generally being predictive of greater improvements - Older adults or individuals with CNS injury may show (transient) increases in grey and white matter volume and microstructural organisation after several months of practice → however the temporal dynamics of neural changes remain unclear - Since aging and brain injury implies a reduction of grey and white matter but learning can increase these, motor skill learning may help to counteract age-related brain structural loss → however these effects might be task specific, raising questions about their generalisability and whether other approaches like physical activity could promote more widespread neural benefits