Expt2151 Lecture Notes - Cut Down PDF

Wk 1: L1 Classification of Motor LEARNING OUTCOMES Describe and distinguish between key terms and definitions in the field of motor learning and motor control Identify the factors that influence the performance of motor skills Describe how motor skills can be meaningfully classified, and...

Wk 1: L1 Classification of Motor LEARNING OUTCOMES Describe and distinguish between key terms and definitions in the field of motor learning and motor control Identify the factors that influence the performance of motor skills Describe how motor skills can be meaningfully classified, and how motor skill classification systems can assist with movement instruction Describe different ways to measure motor skill performance Key definitions: Motor learning: The acquisition, enhancement, or reacquisition of motor skills Motor skills: Voluntary control over movements of the joints and body segments to achieve a specific goal Movements: Behavioural characteristics of specific limbs or a combination of limbs that are component parts of an action or motor skill 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 Why distinguish movements from skill? There a 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 includes aspects of cognitive and perceptual domains of skills 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 Measure 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 classifications of motor skills: Two methods of classification: One-dimensional systems - classification on a continuum, rather than dichotomous 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 required to achieve goal ○ Precision of movement essential ○ Often require good hand-eye coordination and dexterity (writing, drawing, 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) Size of primary musculature: Fine/Gross motor skill classification is useful in various settings Tests for early childhood development based on fine/gross classification Occupational therapists typically work with patients who need help with fine motor skills Exercise physiologists and physiotherapists typically work with patients who need help with gross motor skills Temporal predictability Classification based on specificity of where the actions begin and end. Discrete motor skills ○ Clearly identifiable beginning & end points ○ Typically completed quickly Serial motor skills ○ Series of discrete movements linked together ○ Can sometimes mimic a continuous skill Continuous 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 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 Gentiles taxonomy  Originally proposed as a functional guide to assist therapists assess patients’ movement problems, and select functionally appropriate activities Each category imposes a different 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 individual progress of patients or students 4. Assess effectiveness of a rehabilitation or instruction program 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 Gentile’s taxonomy (environmental demands) Taxonomy of Motor Skills Based on the Environmental Context Dimension of Gentile’s Two-Dimensions Taxonomy Asessing/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 the completion of the movement. Response time - the time interval involving both reaction time and movement time; that is, the time from the onset of a signal (stimulus) to the 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. Discrimination RT - the situation involves more than one signal but only one response, which is to 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 Types 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 of joint ○ Velocity – rate of change of displacement of a limb or object with respect to time Acceleration – 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 for 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 systems assists you to determine how different skills place different demands on the learner Use of a taxonomy (e.g. Gentile’s taxonomy) assists with: ○ Evaluation of learner capabilities and limitations ○ Planning progression of motor skills ○ 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 the skill. Lecture summary: Motor Skills: Require voluntary control of joint and body movements to achieve specific goals. Classification Systems for Motor Skills: ○ One-dimensional Systems - Based on musculature size (gross/fine), movement specificity (continuous/discrete), and environmental stability (open/closed). ○ Two-dimensional Systems – Based on different set of demands on performers in terms of the action and the environment Performance Measures: Outcome measures assess movement results; production measures assess movement characteristics. Wk 1: L2 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 motor learning Definition of motor learning: Motor skills are learned physical behaviors In order to study motor learning it is important to have a clear definition of the term Motor learning is: ○ “a set of processes associated with practice or experience leading to relatively permanent changes in the capability for skilled performance” – Schmidt ○ “a change in the 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 Motor performance Motor learning Observable behaviour - what we can see Inferred from performance - cannot be observed May represent only temporary changes in directly behaviour Relatively permanent changes in behaviour Influenced by performance variables Not influenced by performance variables Motor performance is what we can observe although can only be determined at that time.. Can repeat overtime to see changes (e.g. verbal guidance) 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 perturbations (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 skill learning cannot be directly observed but must be inferred from performance, i.e. by 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 measured on the vertical axis ○ Time or number of trials on the 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 early in practice S-shaped (Ogive) - Learning accelerates in middle phase of practice Performance curve plateaus and asymptotes The negatively accelerating performance curve is 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 improvement seems to have stopped, i.e. a performance plateau It is important to realise that even through performance plateaus may occur, learning often still continues during these times An asymptote is an upper limit of performance that is considered the “best possible level of performance” ○ as long as practice is continued, learning will continue to get closer to this upper limit Merging of performance curves Performance curves may reveal only the initial phase of learning In later stages of learning different shaped curves may merge into negatively accelerating pattern, i.e. the Power Law of Practice (i.e. the performance asymptote) is eventually demonstrated Assessing motor learning - measuring art There are three methods for assessing motor learning from motor performance observations ○ Acquisition ○ Retention ○ Transfer All three methods require repeated observations Acquisition 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 tests 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 - assessing art 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. practising 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 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. Increased consistency 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 Lecture summary Motor learning is distinct from motor performance Motor learning is inferred from the measurement of motor performance Performance curves graphically displays the improvement and consistency of learning during the acquisition phase. Retention tests demonstrate persistence and permanence in motor learning Transfer tests demonstrate adaptability and generalisability in motor learning Skills with shared common elements have greater transferability in motor learning, this is an important point for effective functional exercise prescription Wk 1: L3 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? Theory of motor control Two major theories of Motor Control Motor Program-Based Theory 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. Each component can vary independently. Example ○ The elbow joint has two degrees of freedom: flexion and extension. It can move in these two 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? Closed Loop Control Involves sensory feedback for movement correction Updates movement instructions based on feedback E.g. Walking on unstable surface E.g. Driving a car (visual feedback to know when to turn etc - continuously making corrections based on feedback) E.g. walking on ice (brain sends signal to muscles to walk, although cold, uneven icy ground… so muscles send signal back to brain, so the brain can update movement pattern to avoid slipping Open Loop Control Lack sensory feedback Executed quickly Updates movement instructions based on feedback E.g. Throwing a dart  Motor Program-Based Theory highlights memory-based movements. Instructions from the brain Dynamical Systems Theory focuses on how movement emerges from interactions between the body task and environment aspect Motor Program-Based Theory Dynamical Systems Theory Instruction Source CNS provides instructions Influenced by environmental information Movement Control Managed by a Motor Program Self-organizes into coordination patterns Structure Memory-based structure Body as a complex system Action Execution Organizes, initiates, and executes actions Patterns based on constraints aspect Motor Program-Based Theory Dynamical Systems Theory Advantages Clear, structured explanation of movement Accounts for environmental influences control Emphasises adaptability and flexibility Predictable and consistent movement Explains complex, adaptive behaviours execution Limitations Less adaptability to changing environments Lacks predictability and consistency in Relies heavily on stored memory movements May not account for all variables influencing Can be complex to model and understand movement Motor Program Based Theory A motor program that storess information needed to perform an action Schmidt’s Generalised Motor Program A motor program that controls a class of actions (different actions with a common set of features) invariant features = the unique characteristics that define a generalised motor program I.e. invariant feature = relative time (proportion of time each component of a skill takes to be performed - this remains consistent despite how fast/slow the movement occurs) Parameters must be added to the invariant features in order to meet specific movement demands of a situation. Movement specific parameters = features that vary from one skill to another (to meet demands of a situation) i.e. walking faster/slower or going over an obstacle)  How do we know which parameters to add? Schmidt’s Schema Theory A rule or set of rules that serves to provide the basis for a decision It explains how the generalised motor program operates to control coordinated movement According to this theory there are two main control components ○ Generalised motor program (GMP) responsible for controlling movement coordination ○ Motor response schema which provides a number of rules/parameters to performing the skill in a given situation This allows us to adapt our situations/movements effectively i.e. walking but navigating through a crowded mall Schmidt’s Generalised Motor Program How does motor program-based theory deal with: Open/Closed Loop Control Degrees of Freedom Initiation (starts) is an open-loop control process, but GMP and motor response schema are very performance can be altered during execution if time is abstract/general in nature, and therefore very adaptable. available (closed-loop). Dynamical Systems Theory Body is a complex system that ‘self-organises’ into coordination patterns, based on constraints Non-linear Dynamics ○ Non linear behaviour/systems have unexpected changes/shifts in behavioiur ○ I.e. boiling water; water stays in the same liquid state until it hits a threshold (100 degrees) then it suddenly shifts to a boiling state ○ I.e. transitioning from walking to runnings - spontaneous shift into a completely new behavioural change, changed behaviour pattern to adapt to new requirements 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 Explains how our body naturally adapts to different conditions such as transition from walking to running, change in speed, without any conscious decision making Attractor States ○ Stable patterns of behaviour that your body organises itself into, these patterns emerge from the process of self-organisation to help achieve the movement goal ○ I.e. the deeper the well the more stable the behaviour/ball.. A little disturbance to disrupt the behaiour.. A knock of the ball ○ I.e. a toddler trying to walk but as they speed up their movement may become unstable/fall over, this is because their attractor state for walking is well developed but for running it is not ○ Stability and Attractors Dynamical Systems Theory How does dynamical systems theory deal with: Open/Closed Loop Control Degrees of Freedom Large emphasis on interaction Coordinative Structures (muscle synergies) with environment, and ○ Functionally specific collections of muscles and joints that therefore closed-loop control. act cooperatively to produce an action (e.g. locomotor If there is not sufficient time for synergy) feedback to be useful, then CNS controls synergies, not independent joints/muscles open-loop control occurs. ○ muscle synergies: These structures simplify the control of movement by reducing the degree of freedom so instead of controlling each muscle/joint our nervous system coordinaged them as a group ○ These structures can be intrinsic (develop naturally i.e. walking) or required through practice (i.e. playing music) 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. Wk 2: L1 - Neurons The Nervous System The central nervous system (CNS) is made up of the brain and spinal cord. The CNS controls the regulation of body systems and the processing and creation of memories. The peripheral nervous system (PNS) is made up of all the 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 = functional units of our nervous system, vary in size and function. Generally contain 3 structures; cell body, dendrites, axon Cell Body (Soma): The control center of the neuron, containing the nucleus and organelles organelles essential for cellular function. ○ Responsible for regulating neuron homeostasis/health Dendrites: Branching structures that receive signals from other neurons, integrating integrating information for processing. ○ Receive information from other neurons ○ All neurons have different number of dentrides, some none some 1000s Axon: The long projection that conducts electrical impulses away from the cell body to target cells. ○ Sends signals away from neuronal ○ End of axon is axon terminals, they relay signals by releasing neurotransmissions as synapses 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. ○ Speeds up the transmission of electrical signals ○ Multiple sclerosis = damage to myellin sheath Autoimmune disorder where the immune system mistakinly attacks and destroys the myelin covering the neurons, causing inflammation, scarring which can cause muscle weakness and coordination problems  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 of living cells. ○ Surrounds myelin sheath in peripheral system ○ Vital for repair and regeneration of damaged nerve fibres ○ Provides structural support and helps guide the regrowth or axons Types of Neurons Sensory (afferent) neurons: Transmit information from sensory receptors to the central central nervous system. They detect external stimuli and proprioceptive feedback. ○ Unipolar - only one single axon and no dendrites Motor neurons: Carry commands from the CNS to muscles (causing them to contract). ○ Alpha motor neurons directly innervate skeletal muscle fibers. Alpha motor neurons are located in spinal column, they connect directly to skeletal muscle fibres ○ Gamma motor neurons control intrafusal fibres of the muscle which help with muscle tone and regulation Interneurons: Form complex networks within within the CNS. They integrate sensory input and motor output, crucial for reflex arcs. ○ Act as connectors between sensory and motor neurons ○ Play a crucial role in the integration of processing information, forming pathways that enable complex movement patterns Action Potential Neurons send information through electrical impulses that travel along the axon. This process occurs in several steps; Resting State - neuron maintains a negative charge inside its membrane due to the distribution of sodium and potassium ions (mainly) Depolarisation - neuron receives a signal and the sodium channels open allowing sodium to flood into the cell causing the inside of the neuron to become positively charged Repolarisation - potassium channels open allowing potassium to leave cell, storing the negative charge Hyperpolarisation and Refractory Period - neuron briefly becomes more negative before returning to its resting state. During this time it can’t fire another action potential, ensuring that neural impulses only travels in one direction This process enables the rapid transmission of electrical signals and allows them to communicate effectively. Neural communication 1. Signal Transmission: Neurons form pathways that relay information from the sensory organs to the brain or spinal cord. 2. Synaptic Gap: Between the dendrites of one neuron and the axon of another neuron is a small gap called the synaptic gap. 3. 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 that it can pass through the synaptic gap and into the next neuron. After the action potential reaches the end of the axon, the neuron needs to communicate with other neurons or muscle fibres. This occurs at the synapse, where electrical signals are converted into chemical signals. The arrival of the sanction potential at the axon terminal causes the release of neurotransmitters (little messengers) into the synaptic gap. These neurotransmitters bind to the receptors on the next neuron/muscle, either exciting or inhibiting it, depending on the type of neurotransmitter. If the signal is strong enough it will trigger an action potential to the next neuron, continuing the transmission process. This combination of electrical and chemical processes allows complex neural communication nd coordinated response such as movement. Wk 2: L2 - Central Nervous System The central nervous system (CNS) is made up of the brain and spinal cord. The CNS controls the regulation of body systems and the processing and creation of memories. The peripheral nervous system (PNS) is made up of all the 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. Anatomy of the Central Nervous System 1. Central Control Center: The brain is the central control center for the body. Every bodily function is controlled by the brain. 2. Conscious and Unconscious Control: Some functions are controlled consciously, such as bending your arms. Others are unconscious, such as breathing or blinking. 3. 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: support celss, provide neurons with nutrition so hey function well The brain is made uo of three main parts; Brainstem; Cerebellum Cerebrum Functions of Brainstem, Cerebellum, and Cerebrum Brainstem: The brainstem controls basic functions like breathing, swallowing, blinking, and vomiting Cerebellum: The cerebellum controls muscle movements, maintains posture, and balance. Cerebrum: The cerebrum is the largest part of the brain and controls higher thought processes. Cerebrum 1. Frontal Lobe Responsible for executive functions, such as planning, decision-making, and personality. Controls voluntary movements and speech. 2. Parietal Lobe Processes sensory information, including touch, temperature, pain, and pressure. Aids in spatial awareness and navigation. 3. Temporal Lobe  Processing auditory information, language comprehension, and memory. Plays a role in emotion and recognition. 4. Occipital Lobe Processing visual information. It receives signals from the eyes and interprets them to create our perception of the world. Primary motor cortex is responsible for initiating movement and controls fine motor skills i.e. typing, playing instruments Priotal area of the brain (primary somatosensory cortex) is responsible for sensory information that we receive from the body. Helps us to integrate information from the environment and allows us to navigate/change movements based on surroundings Premotor area: responsible for helping us plan movements and coordinate sequences i.e. typing out a whole sentence Supplementary motor areal planning and subsequent movement control The Basal Ganglia Deep in the brain Movement initiation and planning (act as a bridge between our intentions to move and actual movement) Control of force and muscle tone ○ Regulates force of movement, determines how much force we apply for different movements i.e. picking up a glass vs lifting a heavier weight differs in amount of force Coordination between antagonistic muscles ○ Coordinates complex movements, without basal ganglia our movements would be unorganised Helps to ensure we dont make unnecessary of involuntary movements, helps to inhibit unwanted movements Helps regulate motor learning and habit formation (as we repeat movements, the basal ganglia refines those movements, making them more automatic and efficient over time) If doesnt function cna be seen as Huntingtons disease The Cerebellum Little brain Receives sensory information from the spinal cord, cerebral cortex and brain stem Sends out motor signals that travel to spinal cord Coordination of movements - ensures movements are smooth and accurate Error detection - sends signal of movement to muscles and a copy of this movement to the cerebellum so it can plan based on sensory feedback and muscle, and can send out corrective plans/movements to ensure we are doing the intended movement  Hand-eye coordination Timing and posture control Motor learning Damaged cerebellum → Ataxia ○ Characterised by clumsy, uncoordinated movements The Brainstem Located directyly under the cerebral hemisphere and is attached to the spinal cord Basic life functions Motor pathways Consists of; ○ Pons; acts as a bridge between the cerebral cortex and the cerebellum. Various neural pathways terminate and pass through the pons as they travel from the cortex to the spinal cord. Pons is responsible for controlling basic bodily functions i.e. chewing, swallowing, breathing ○ Medulla Oblongata; extension of the spinal cord that regulates internal physiological processes such as respiration, regulating heartbeat ○ Reticular Formation; complex network of nuclei and nerve fibres, structure serves as a link between sensory receptors of the body and the motor control centers in the cerebellum and cerebral cortex. Main function is to integrate sensory and motor neural impulses to ensure smooth and coordinated. The reticular formation has access to all sensory information and can influence the central nervous system either by inhibiting or increasing central nervous system activity, which then in turn affects skeletal muscle control. Structure and Function of the Spinal Cord Grey Matter (unmyelinated) 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. Primarily contains neuron cell bodines and axons It features two pairs of horns that play important roles in motor control. Dorsal Horns: Process sensory information ○ contain cells that process sensory information. sensory neurons from various receptors in the bodies, synapse or or finish here. Ventral Horns: Terminate on skeletal muscles to control movement ○ closer to the anterior side of the spinal cord. ○ here we have the alpha motor neuron cell bodies, whose axons terminate on skeletal muscles and help us to control movement. ○ The spinal cord also contains interneurons, specifically renal cells, mostly ○ located in the ventral horns. These interneurons influence alpha motor neurons, often by inhibiting them temporarily, allowing neurons to reset and fire again shortly within the spinal cord. White Matter (myelinated) The white matter, surrounding the grey matter, is composed of myelinated axons that carry signals between the brain and the body. It allows for rapid 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 Tracts These enable the brain and the body to communicate effectively, ensuring our smooth and co-ordinated movement. Ascending Tracts They transmit sensory information from the body to the brain. These tracks typically consist of sequences of two or three neurons that carry information from specific sensory receptors related to touch proprioception pain and temperature. 1. Dorsal Column: Transmits proprioception (he body's awareness of its position and space), touch, and pressure information to the brain. 2. Anterolateral System: Carries pain, temperature, and some touch and pressure signals. 3. Spinocerebellar Tracts: Relay proprioception information directly to the cerebellum for movement coordination. Both the dorsal column and anterolateral System synapse in the thalamus before continuing to the sensory cortex. These pathways cross over in the brain stem, meaning that sensory input from one side of the body is processed on the opposite side of the brain. Descending Tracts these are involved in motor control. they can be categorised into two primary groups → Pyramidal (Corticospinal) and Extrapyramidal the pyramidal tracks or the corticospinal tracts ○ Approximately 60% of these fibres arise from the primary motor cortex, and most of them cross over in the brain stem before continuing down the opposite side of the spinal cord. Extrapyramidal ○ unlike the pyramidal tracks, most of these extra pyramidal tracks, um or fibres don't cross to the opposite side. ○ These tracks are essential for posture, control and regulation of muscles in involved in hand and finger movements. Tract Type Origin Function Pyramidal (Corticospinal) Cerebral Cortex Fine Motor Control Extrapyramidal Brainstem Posture and Gross Motor Control Sensory and Motor Pathways ascending descending Sensory Pathway Motor Pathway Carries information from the body to the brain Carries commands from the brain to the Uses sensory neurons muscles Permits us to feel pain, touch, temperature, and Uses motor neurons pressure Allows for voluntary movements and reflexes  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 muscle tone, with pyramidal fibers crossing in the brainstem. WK2: L3 - 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 1. Connection Point The neuromuscular junction links alpha motor neurons to muscle fibers. 2. Signal Transmission Nerve impulses are transmitted across this specialized synapse. 3. Muscle Response The transmitted signal triggers muscle fiber contraction. Motor Unit Composition and Variability Fine Movements Gross Movements Adaptability Eye muscles have fewer fibers per motor Larger muscles can have up to 700 fibers The variable composition of motor units unit, sometimes just one. This allows for per motor unit. This enables powerful allows for a wide range of movement precise control. contractions. 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 The same physical movement can activate different brain areas depending on the task's cognitive intent. Conclusions 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 organizes motor activity Wk 3: L1 Touch and Proprioception Neural Basis of Touch When we touch an object the mechsnoreceptors in our skin are activated Mechanoreceptors: These receptors are sit within the dermis layer of the skin and they provide our central Provide the CNS with information on pain, temperature, and movement. They detect mechanical changes like pressure and vibration. The central nervous system then uses this information or uses this sensory input to guide our motor actions. Mechanoreceptor send signals to the brain which then process the information to help us make necessary adjustments during movement. This tactile feedback is what allows us to adapt to changes in the environment during motor tasks. The skin contains different types of Mechanoreceptors, which are each specialised to detect certain sensations. ○ Merkel discs, which respond to pressure, giving us information about the texture of an object. ○ Meissner’s corpuscles which help us perceive light touch and with grip control as well. ○ Pacinian corpuscles detect deep pressure and vibrations ○ Ruffini endings which sense skin stretch, and they help us to understand the position of our limbs. all of these together, all of these receptors together, help us to perform delicate, precise motor tasks by continuously sending feedback to our central nervous system. The Role of Tactile Sensory Information in Motor Control Tactile information is important for executing a really wide range of motor skills, and lots of researchers agree that touch plays an important role in in in these different aspects. The five key movement characteristics that are typically influenced by tile feedback are; Movement accuracy Tactile feedback significantly influences the accuracy of fine motor skills. Is significantly impacted when tactile feedback is is compromised. ○ some research shows that when tactile sensations from the fingertips are reduced or removed, like if we use anaesthesia, the precisions of tasks like pointing, reaching, typing, playing instruments are diminished. Movement consistency the ability to repeat movements with similar precision. This study that we have here analysed the movement of the right index finger during typing with and without tactile sensation. They had 12 expert touch typers, type sentences on a keyboar without any visual feedback.then removed that variable and performed the trial with nothing else added. Then after this initial trial, they, anaesthetized the right index fingertips. They repeated the same typing task and found that when tactile feedback from their right finger removed, there was a significant increase in the variability of all the kinematic measures. They found higher the variable error meaning the more variation they had in the fingertip movement without tactile information - the movement becomes less reliable, leading to a higher rate of errors. Movement timing Tactile feedback also plays an important role in movement timing, particularly in rhythmic activities that involve contact with objects or surfaces such as juggling or walking. This study showed that adding a tactile like a Velcro strip on the top of a circle improved the timing accuracy of a circle drawing task. adding tactile information helps the brain coordinate movements more accurately because it provides us with sensory cues at the right time to do certain things.  Movement force Our sense of touch also helps us adjust the force in motor tasks. For instance, when adjustments we lift up a cup, tactile feedback helps us regulate the grip force so we can lift up the cup without spilling what's in it. the central nervous system continuously during such movements, enabling us to adjust group force as necessary without any tactile feedback. In movements like this, we would struggle properly to regulate force, leading to awkward, less effective movements. If you've ever tried to grab a a bottle or a cup or something small where you don't need a lot of force, if you've tried to grab it with a lot of force, often you end up having clunky, more rigid movements, and so things aren't quite as fluid. Estimate movement Aids in estimating movement distance, especially when the task involves both the distance start and the end of a movement involving touch in pointing tasks. Research by Rowan Gordon demonstrated that participants could estimate the distance to a target more accurately when they could feel the surface at the beginning of the end of the movement. So, the tactile feedback here supports the central nervous system in calculating how far and how, how far and how fast to move. Proprioception refers to the sense of our body's position and movement, allowing us to perceive limb position So where our limbs are located in space movement direction, the path that our limbs are taking, movement velocity the speed at which our limbs are moving and muscle activation, the tension of force being exerted by our muscles, this internal sense comes from Proprioceptors. There are specialised sensory neurons located in the muscles, tendons, ligaments and joints. These receptors provide continuous feedback to the central nervous system about the status of our limbs and our body, which is important for coordinating and executing smooth and controlled movements. Proprioreception is essential in both closed loop and open loop motor control systems closed loop control systems; Proprioceptive feedback allows for continuous adjustments during movement, helping us maintain accuracy and co-ordination. So we use that feedback to keep adjusting in an open loop control system, the movements are preplanned and proprioceptive. Feedback plays an important role… plays a a limited role during the execution phase, but is super important in the planning and the learning stages. When we're walking, even when you close your eyes, you can still walk in a straight line without stumbling, because proprioceptors are constantly providing your brain with the information about the position of your legs, the angle of your joints and the tension of your muscles. This internal feedback allows you to adjust your steps in real time without relying solely on vision. Limb position Movement direction Movement velocity Muscle activation Neural Basis of Proprioception  Muscle Spindles - Detect changes in muscle length They're embedded within the skeletal muscles, and they're responsible for detecting changes in muscle length and velocity of those changes. The spindles contain specialised sensory receptors called type one a axons, and they're wrapped around the centre of the intrafusal muscle fibres. When a muscle stretches the axons detect the change in the length and send a nerve impulse to the spinal cord and the brain. The muscle spindles are highly concentrated in the muscles that require precise control. these muscle spindles also play an important role in stretch reflexes like the knee jerk. When the muscle stretches, the spindle sends rapid signal to the spinal cord, and that triggers a reflective contraction to protect the muscle from overstretching. Golgi Tendon Organs - Sense muscle tension, acting as a protective mechanism to prevent injury. they are located at the junction where the muscles connect to the tendons. responsible for detecting changes in muscle tension rather than in length. consist of Type one B sensory axons, and they sense tension or force when muscles contract. When excessive force is applied, the Golgi tendon organ sends signals to the CNS, which then adjusts muscle contractions to avoid damage or over exertion. This is how the Goggi tendon organs helps to prevent injury by ensuring that forces exert exerted by the muscles is not too excessive - a safety mechanism that protects the tendons and the muscles from strain or rupture during intense movements. Joint receptors - Detect joint position and motion. They're found in the joint capsules and in the ligaments detect changes in joint angle force and rotation. These receptors include the ruffini endings, pacincian cospuscles and golgii like receptors. they're particularly sensitive to the extremes of joint movement. When the when the joint reaches its its maximum range of motion, these receptors send signals to the central nervous system to prevent ovary extension. Joint receptors are essential for maintaining joint stability and ensuring smooth coordinations of complex movements. gymnastics, martial arts and that kind of thing where joints are pushed to their limits. These proprioceptive signals are transmitted to the central nervous system through affluent pathways, where they're integrated with information from other other sensory systems, like vision and touch which helps to coordinate these movements. The brain then uses this proprioceptive input to control the spatial and temporal aspects of movement, essentially making sure our limbs move where and when they should. In addition to the role of proprioception in movement, correction and planning, it's also important for coordinating control, particularly in tasks that involve the synchronisation of multiple body parts or segments. Proprioreception provides important feedback that allows us to maintain postural control and achieve spatial temporal coupling between our limb and limb segments Coordination Control Postural Control proprioceptive feedback, often in conjunction with tactile sensory feedback, is important for providing the central nervous system with information to regulate upright posture. they used the tendon vibration technique to alter progressive feedback by vibrating the Achilles tendon. They induced a backward tilt in the participants by approximately three degrees which affected their postural alignment and shifted their centre of pressure backwards. This demonstrates the disrupt that how the disruption of proprioceptive feedback can lead to quite noticeable shifts in postural stability, highlighting the importance of  accurate progressive information for maintaining upright posture. the ability to synchronise movements between different limbs or limb segments. Spatial-Temporal Coupling Between Limbs and Limb Segments → how movements of different body parts are coordinate in both space and time. Bimanual Coordination Intra-limb Coordination Proprioreception plays an important role here in ensuring that limb movements are properly aligned and timed. e.g. of how important proprioception is in people who have sensory neuropathy (a condition where proprioceptive feedback is impaired due to damage to sensory nerves). Shows how they have difficulty coordinating multi joint movements such as reaching for a target. So the limb positions of the person with sensory neuropathy on the right hand side here and in their path that they take reaching for targets versus the people without any sensory neuropathy on the left hand side. Here, the lack of proper reception here leads to poor coordination between different joints, resulting in inaccurate or erratic movements. This points out how essential app proprioceptive feedback is in ensuring smooth and co-ordinated between joint movements in actions like reaching properception is also important for bimanual co-ordination, and coordinating movements between two limbs. When we perform task study use both arms simultaneously, such as rowing, Proprioception helps ensure that both arms move together harmoniously. If proprioception is disrupted, the arms may become de synchronised and often leads coordinating errors. intra limb co-ordination - Researchers have looked at this, demonstrating that Proprioception influences the coordination between different segments of the same limb, such as the upper arm and the forearm. Without this feedback, the synchronisation between the upper arm and the forearm can break down, leading to jerky and uncoordinated movements. 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 specific tasks. Wk 3: L2 - Vision Anatomy of the Eye Cornea: Transparent, dome-shaped front part that helps focus light as it enters the eye. Pupil: Central opening that adjusts size to control light entry (regulate the amount of light that enters the eye). Iris: Surrounds the pupil, controls its size (diameter), and gives eye colour. Lens: Flexible, adjusts shape to focus light onto the retina for clear vision. ○ This adjustment allows us to see objects clearly at varying distances. Sclera: the white part of the eye, that encases the eye's internal structures. It provides protection and maintains the eye's shape. Also serves as kind of an attachment site for the muscles that are responsible for our eyes movements. Neural Components of Vision Image Processing At the abc of the eye is the Retina; where the light is converted into neural signals. couple of different photoreceptors; Rods; specialised for low light conditions. They help us see in dim light and are spread out across the retina's periphery. Cones; are concentrated in the central part of the retina, known as the favela. They're responsible for our sharpest vision and our colour perception. They work best in bright light. When the when light hits the retina, it's bent by the cornea and the lens, creating an inverted and reversed image. This process is essential for accurate visual perception and helps us make kind of sense of the world around us. Visual Pathway to the Brain Movement accuracy - Tactile feedback significantly influences the accuracy of fine motor skills The optic nerve carries visual information from the retina to the brain. At the optic chiasm, some of the nerve fibres cross over to the opposite side of the brain, allowing us to integrate information from both eyes. The visual cortex is located at the back of the brain processes this information that we're receiving from the octave nerve optic nerve. It combines the images from both eyes to create a single, cohesive view of the world. Seeing with both eyes gives us depth perception, which is crucial for judging distances and navigating our environment. It's what allows us to perceive the world in three dimensions. Monocular vs. Binocular Vision We know that using binocular vision or both eyes to see is important but there are instances where we also use monocular vision. There are some studies that indicate that tasks become more accurate and more efficient with our binocular vision to both eyes. For instance, when people use only one eye, we can still reach and grasp for objects. But the accuracy declines as the distance to the object increases something that you probably know more about using both eyes or a binocular vision is that it's super important for depth perception. Without binocular vision, people often misjudge distances and object sizes. These misjudgments aren't um, corrected during the task, which highlights the importance of having both eyes working together. Research shows us that individuals using monocular vision may also move their heads better to gauge the size and distance of objects. Binocular vision benefits include static tasks like reaching and grasping things and in activities where we're walking and encountering objects, it helps us to perceive the 3D characteristics in our environment, and it enables us to navigate around or over obstacles with greater accuracy. This also applies when we're intercepting moving objects. So, like catching, uh, some experiments show us that when participants have only one eye used to hit a moving target, they miss more frequently compared to when they're using both eyes. For people with monocular vision; Two of the biggest changes will occur will be the loss of their peripheral vision to their affected side forabout 30% of their vision and then a loss to their depth perception. This does not necessarily mean that you can't do everyday things. People with monocular vision will do is increase their scanning. So how often they turn their heads to be able to compensate for that missing peripheral vision. So when you're driving a car, you might need to turn your head a little bit further around to do a shoulder check because you don't have that peripheral vision. Central vs. Peripheral Vision Central Vision (the sharp, detailed vision that we use to focus on objects directly in front of us) Middle 2 to 5 degrees of the visual field Object size, shape & distance Walking path Peripheral Vision Limb movement Spatial features covers pretty much every every area outside of our central vision and helps us to detect movement and spatial relationships. For most people, the visual field extends approximately 200 degrees horizontally and 160 degrees vertically. Consider the task of reaching for a cup on a table. Central vision helps us focus on the cup size and shape, and the distance guides our initial hand movement as we reach for the cup, our peripheral vision tracks our hands movement and provides us with real time feedback to adjust our reach and our grasp. If we look at locomotion activities i.e. walking and running Central Vision also plays an important role here by helping us stay on designated path while peripheral vision provides us with information about the spatial features like obstacles or uneven surfaces. studies reveal that people without peripheral vision that they struggle to adjust their path and avoid obstacles. So this would explain why people with monocular vision, like my friend with her glass eye, steer away from things like trial running because they struggle with obstacles and uneven surfaces. Another important thing with peripheral vision is the concept of optical flow, and this is the pattern of motion. What we perceive as we move throughout our environment, peripheral vision captures, captures this flow of visual information, gives us cues about speed, direction and spatial relationships. Whether we're walking down a hallway or again driving in a car. Optical flow helps us to main balance, judge distances and adjust our movements. As we move, the peripheral field re registers the change in the scenery, which informs us how fast we're going, whether we need to slow down or change direction. Optical flow is especially useful in situations where movement is continuous as it provides us feedback about our relative position to other objects. Two Visual Systems for Motor Control Researchers have proposed that our visual visual system might consist of two distinct pathways. ○ the ventral system, and it processes detailed visual information such as colour and form. It's linked to conscious awareness. Anatomically, the ventral stream processes visual information through a pathway from the primary visual cortex to the temporal lobe, ○ The dorsal stream handles spatial information and guides our movement and often without conscious awareness. the dorsal stream routes information from the primary visual cortex to the posterior parietal cortex The ventral stream allows us to recognise and describe what we see, while the dorsal stream helps us to understand where objects are and how to interact with them. For example, someone with damage to the ventral stream might not consciously perceive an object size or orientation, but can still manipulate it accurately. Whereas, damage to the dorsal stream might impair the ability to guide movements based on spatial information These distinctions help us helps us understand how different types of visual information are used for perception and action. Perception-Action Coupling “We perceive in order to act and we act in order to perceive.” action coupling refers to the coordination between what we see and how we move.  It's an essential part of how we interact with our environment. A common example here is hand eye co ordination, like when you play a video game or even try to unlock your door your eyes. Take the information about the target and your hand follows to complete the action. This coupling occurs because the vs the visual system and motor system are interconnected. When you look at an object the brain the brain processes spatial information to guide your movement. For instance, when you're trying to kick a moving ball, your eyes track the ball's movement provide continuous feedback to your legs and feet. This ensures that you can adjust your timing and your force to make contact with the ball at the right moment as your hand or foot moves toward towards a target. Your eyes don't just provide the initial information. They keep providing feedback throughout the movement. In most tasks, your eyes actually lead the movement. Research shows us that the eyes move first, providing the brain with essential details about the target. For example, if your hand undershoots the target, your eyes help guide a secondary adjustment to hit it correctly. This type of co-ordination isn't limited to eye and hand movements. It applies to eye foot movements during activities like walking or stair climbing, and it can even involve other body parts. The key here, really, is that perception and action are tightly integrated and that allows us to navigate our world with precision and fluidity. Time Needed for Vision-Based Movement One of the critical factors in motor control is how quickly we can actually use our visual information to make adjustments for our movements. So research has consistently shown us that; The minimum time required to process visual feedback and make corrections is between 100 to 160 milliseconds. This means that if you make an error in your movement, you need at least this amount of time to detect and correct it before completing the action. This has been demonstrated through various experiments where people performed aiming movements with lights turning on and off when the lights went out. During the movement, participants couldn't see their target and their accuracy dropped. But when the lights were on, they could use visual feedback to correct their aim - showing us how important vision is in movements like these tasks. Interestingly, when people know in advance that they might need to make a correction, they can process visual feedback even faster, sometimes in under 100 milliseconds. This anticipation allows the brain to prepare for possible adjustments and speed up their reaction and their response time. In one experiment, researchers moved a target after their participants had already started reaching for it. The participants were able to adjust their movements based on new visual information in about 100 to 150 milliseconds. In other studies, such as those using uh, prism glasses to distort vision, they found similar correction times ranging from 100 to 160 milliseconds Although there are a few different factors that can influence this processing feedback If you're performing a highly familiar or practise task like playing a sport that you know your brain, you may use visual feedback faster again especially if you're anticipating the certain actions of movement But for complex or unpredictable tasks where real time adjustments are needed, the brain requires at least this 100 or 160 millisecond window to detect an error and make the the correct movement adjustment. So whether you're reaching for a moving object correcting our posture during walking or adjusting the force of a movement mid action vision here is important for providing ongoing feedback. Understanding the time limits of this feedback helps us to appreciate the precision and speed of our visual motor system and the importance of it in everyday activities. 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. when we're moving towards an object/object towards us i.e. catching a ball or avoiding a collision. Our vision provides us important information about when to initiate an action. This is based on time to contact or how much time remains before an object reaches us or we reach the object and it's determined by how the image of that object grows on our retina. The concept of Tau was introduced by David Lee in 1974 and Tau is the optical variable that helps our brain estimate time to contact, based on what on the rate at which an object's retinal image expands. Essentially, as the object gets closer, its image on our retina expands faster. Tau measures the inverse of this expansion right and tells us when an object will make contact, triggering us to make an appropriate action. It is a powerful tool because it works automatically. There's no need for us to consciously think about distance or speed, for example, when we're driving a car and the car in front of you suddenly slows down, our brain uses Tau to determine how hard when and how hard to break. Tao handles that by processing the changing visual information on our retina. The main advantage of Tao is its predictive nature. It allows us to make timely decisions on when to act, even in dynamic environments. The rate of this visual expansion helps the brain predict the right moment to perform an action 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 100-160 ms, 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. Wk 3: L3 Vision Catching, striking & locomotion Fundamental Movement Skills Body management skills - i.e. balancing Locomotor skills - i.e. running, skipping, hopping, Object control skills i.e. catching, striking, throwing we know is that Children that are proficient movers are more willing to participate in sport, which leads to higher self esteem and self-confidence. This allows Children to get greater enjoyment out of sport and hopefully make physical activity part of their their life as they get older. Low fundamental movement skills is often a major barrier to participating in sport and physical activity and is actually one of the main reasons why children will drop out of organised sport. Catching catching a moving object is a complex motor skill that requires precision co-ordination between the eyes, brain and the hands. It's important for sports like baseball, cricket and soccer but it's also something that we use in everyday activities io.e. Keys falling off the table. To catch successfully, a person must be able to estimate the trajectory, speed and timing of an object movement and make the which makes it a kind of perceptual challenge as all as well as a motor challenge hatching can be broken down into three main phases. Phases of Catching  1. the person must move their arm and their hand toward the oncoming object. This movement is based on visual information about the object's speed and direction. 2. hand must be shaped to catch the objects, so this involves opening the fingers and adjusting the hand's orientation to match the size and form of the object. 3. the fingers must close around the object to catch ensuring a secure grasp as the object makes contact with the hand. some researchers showing that successful catching or successful catchers begin preparing their hand for the catch earlier in the ball’s flight, compared to those who fail, this was a study in 11 year old boys, and they found that the boys successfully caught a ball, position their hands and fingers about 113 milliseconds before contact - time to process visual information is quite minuscule as well. Vision of the Object and Catching A lot of this stuff is happening subconsciously, so something that's really interesting is that visual contact with the object is not necessary for the entire duration of the flight. We know that we only need visual input during key moments, specifically at the beginning of the object's flight path and just before it reaches us. Some older research from Elliott and colleagues found that people can catch a ball by only seeing brief snapshots of the balls flight. This suggests that our visual system takes samples of the object's movement rather than needing to continuously track it. This ability to process intermittent visual data is particularly useful in sports like soccer or cricket, where either the ball's obstructed by other players or where you might need to, take your eyes off the off the ball to be able to perform another skill. cricket or baseball, for example, the batter might hit the ball as a fielder. you've seen where roughly the ball's gonna go. You turn. Put your head down, run into the outfield to try and make the catch. Then you search again. Find the ball just before it makes contact with your hand so that middle part of the ball's flight is not always necessary for successful catching. Tau and Catching Initial body positioning Grasping Tau is particularly important for skills like catching. As an object moves closer to us, the image it casts on the retina grows larger at an accelerating rate. Tau gives us a sense of how much time before contact, so we use Tau to decide when to start or adjust movements like we have here catching. When we're catching, we rely on towels to determine when to close our hands or adjust our body's position to intercept an object at the right time. The brain calculates tau without us consciously thinking about it. It's an automatic process that relies on continuous visual feedback. For example, if we're catching our baseball, our brain tracks how quickly the ball size is increasing as it approaches. Without us actually needing to know the speed of the ball our visual system will compute how soon the ball will reach our hands based on its changing visual size, guiding it to us in time for us to catch it. With the time to contact thing, we can break it down into two different phases. our initial positioning when the ball's fire away, we primarily use visual cues to adjust our body position. This involves moving our feet or adjusting our students to line up with where we predict the border land. We aren't necessarily concerned about the precise timing but positioning ourselves effectively. Then linking to prior slide…this is where we make estimations about the trajectory ofthe ball. Then as the ball becomes near we use Tau again to determine the final path of the ball, and it helps us to determine the time that we need to close our hands to make that catch.  This is important because estimating time to contact can lead to missing the catch entirely or closing our hands too early or too late. And we often refer to these as grasping errors. skilled players. such as baseball outfielders develop the ability to read time to contact information with more accuracy with practise. These types of athletes are able to fine tune their sensitivity to tout so they can adjust their actions with more precision. This is why you see some spectacular athleticism in different types of sports, like goalkeeping and soccer. these type of athletes can are better at interpreting the visual information like a small ball speed and trajectory and reacting to it at the right moment. Vision of the Hands and Catching Smythe and Marriott showed that when people couldn't see their hands, they did have more difficulty positioning them correctly to catch a ball. But what they did find is that experience play plays a major role. More experienced catchers like those that participate in ball catching sports, cricket, baseball things like that rely less on seeing their hands because they've developed a greater sense of proprioception in contrast, the the less skilled catchers depend more on visual feedback to coordinate their movement. Striking Similar to catching The action requires precise coordinations between our vision and our motor control to effectively time and execute the strike so striking an object is generally involves three different phases.. Phases of Striking Preparation ○ positioning and timing the movement to align with the object's trajectory so similar to catching again. Execution ○ the actual act of swinging, where coordination between the eyes, hands and body is super important. Follow-through ○ completing the motion after contact with, which helps a bit in controlling the force and direction of the strike. Vision and Striking in Sport An older study by Hubbard and Singh revealed that professional baseball players track the ball only up to a certain point before initiating their swing. Interestingly, the swing duration was consistent, indicating that players adjust the timing of their swing based on the ball speed in line with that Tua strategy. Some other research, also in baseball batting, confirmed that major league players track the ball for longer than less experienced players. Early vision is important Perception-action coupling ○ Involving the initiation of stepping with the front foot to the swing players adjust these actions based on the speed of the ball coming towards them. ○ the front foot movement, this temporal coupling. So the timing here ensures, well, coordinate stripe and allows the body to adapt to varying pitch speed or the flight of the ball speed. study on cricket batsman had high and low skilled batsmen and they faced some different leg spin bowlers. Wearing some optical inclusion glasses. These glasses were used to control the visual information available to the batsman. In each trial, the vision was manipulated in three different ways. The first one was the the vision was blocked before the ball was released so the batsman could only see the bowler's delivery action. The second one was the ball was blocked before it bounced, allowing them to see um, the ball in the the pre bounce flight the third condition was that it wasn't blocked at all. hat they found was that the skilled batsman were better able to use earlier information from the ball's pre bounce flight to guide their movement and successfully make contact to the bat. So able to predict the mo the the ball's flight path a little bit better than the lesser skilled batsman. Locomotion Fundamental skill for daily activity the movement of a person from one place to another, typically involving co-ordinated patterns of muscle activity. The Rhythmic Structure of Locomotion Central Pattern Generators: Groups of nerves (neural circuits) in the spinal cord that create the basic rhythms for movements - like walking and running. ○ They're like the body's internal metronome and creates a basic rhythm for these types of actions. Adapt our walking and running patterns based on how fast we’re moving. central pattern generators is that they can generate these rhythmic patterns without input from the brain. This means that our spinal cord can independently create these movement rhythms necessary for actions like walking and running. We know that central pattern generators adjust the rhythmic patterns based on our speed. For instance, when we walk slowly, our arms and legs move in a 2 to 1 ratio. That is, that our legs move twice as fast for every one swing of our arms. As we start to walk faster, this ratio changes and our arm leg movements become more synchronised, reaching a 1 to 1 ratio at high speeds. When we transition from walking to running, the central pattern generators help us adapt our movement to match increasing speed. This adjustment ensures a smooth and efficient locomotion helping our movements remain co-ordinated even as we change speeds, It fits in with the dynamical systems theory.. Dynamical Systems Theory and Gait Explains movement coordination Allows adaptability theory proposes that movement patterns emerge from the interactions of multiple subsystems within the body that each contribute in this case to overall locomotive function. The dynamical systems the reviews movement patterns as a result of interactions among several systems. When we're doing locomotive activities, we have the neural system that controls signals generated by the nervous system, the musculoskeletal, which is the physical structure of our muscles and our bones, and then also our sensory system. So feedback from such aspects of our sensory system like vision perception and touch. So at different speeds our gate pattern adjusts in response to changes in stride, length and frequency. Relating to walking/running e.g. - We've also got the adaptability that the dynamical systems theory kind of allows us to try and understand, and this theory explains how our gate adapts to various conditions so that when we're walking on uneven terrain, it requires alterations in our stride length and in our in our balance. These adjustments are dynamically regulated through the interactions between our neuromuscular and sensory systems. Understanding dynamical systems theory can help develop rehab strategies for different types of gait disorder disorders by analysing how different subsystems interact. exercise professionals can help design targeted interventions to improve gait and mobility in people with movement impairments. Head Stability and Locomotion affect our different type of locomotion; Visual stability ○ Essential for maintaining balance and coordinate movement when we move. Keeping our heads stable has several important effects  ○ For our visual stability. Keeping a stable head will help us maintain clear and ○ steady visual field, which is important for tasks like navigating through crowded spaces and avoiding objects. ○ A stable head also ensures that our head movements are in sync with the rest of our body, which helps us maintain overall balance Balance and coordination ○ Total coordiantion research has shown us that good head stability contributes to more efficient and stable gait. For example, when walking focusing on a fixed point ahead helps us in maintaining head stability and consequently helps us improve our balance and reduces the risk of stumbling vision is probably one of the more important things that most of us need when performing local motor activities. ○ It provides us with information that is super important in navigating our environment effectively. Vision and Locomotion I.e. long jump run up - this often involves two main phases ○ initial acceleration phase - During this phase, athletes focus on building speed and maintaining a consistent stride pattern. This pattern is largely predetermined and doesn't require immediate visual adjustments. Athletes concentrate on accelerating to reach the optimal need for optimal speed for jumping. the zoning in phase - as athletes in long jump are approaching the takeoff board, they enter This phase uses the visual feedback for making final stride adjustments. So first we have the time to contact information. Athletes use the visual information to estimate how much distance remains until they reach the takeoff board and adjust their stride length accordingly. This information is based on visual cues such as distance of the board and the rate at which we're approaching to ensure they land precisely on the takeoff board. Athletes adjust their stride length based on this visual feedback received, and these adjustments are super important in ensuring a successful takeoff. as athletes get closer and closer to the takeoff their stride length becomes a little less predictable and a little bit more variable as they use visual information for precise movement adjustments. Avoiding Obstacles It's also important for other dynamic activities like sprinting and obstacle navigation, where accurate timing and positioning. We rely on vision to gather information about obstacles in our path including things like size and shape. By observing the size and shape of an obstacle, we can determine how much space is needed to avoid it. Larger or irregular shaped objects require more adjustments compared to smaller, more predictable ones. We can also estimate the distance from the target and its position relative to our trajectory. This helps us in blending required adjustment in our movement path. 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 ○ adjustment varies based on the perceived fragility of the obstacle, we tend to lift our leg higher to avoid potential contact, while for solid objects, the required clearance that we perceive, maybe less. We also modify our step pattern depending on the obstacles, characteristics, for instance, when stepping over a low obstacle, we might take shorter, quicker steps. However, when we're stepping over higher obstacles, we may adopt for a more deliberate, higher stepping motion. These types of strategies are important for safe navigation in dynamic environments, like when walking through a crowded area or running in the bush or on uneven surfaces. Our ability to quickly assess and adjust movement patterns helps us prevent accidents and maintain balance. Conclusions 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. Wk 4: L1 - Attention Attention = The cognitive process of selectively focusing on specific information while ignoring other stimuli. This selective process is really important in motor performance, where athletes or performers in different skills need to philtre out irrelevant information and concentrate on essential details. For example, a football player must focus on the ball and the opponents but ignore the crowd noise and things like that without intention Characteristics of Attention Less efficient attention operates under a few key characteristics; 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 ○ suggests that our cognitive system can only handle a certain amount of information at any given time. It's sometimes called the filter theory, and this being able to handle a certain amount of information creates a kind of bottleneck. So in terms of motor skills, this means that when too many stimuli I demand attention, we're forced to prioritise some and completely ignore the others. Central Resource Theories (CRT) ○ arguse that attention comes from a single finite ○ Pool of attention. No matter how many tasks we're trying to manage, we can only allocate information from this one limited pool. If we're trying to do too many things once our performance in each of them will suffer. 1. Single Resource Pool a. Attentional resources drawn from one pool 2. Capacity Limit a. Total capacity is fixed and limited 3. Resource Allocation a. Distributing resources for multiple tasks ○ Kahneman’s Attention Theory (is a CRT) Attention is allocated based on perceived task demands. The availability of resources influences attention. Resource capacity is determined by both the task demands. It proposes that attention is a flexible resource that can be distributed across tasks depending on both their demands and the individual's mental state. For example, when you perform a complex motor skill like those we see in gymnastics, the athlete often allocates more attention to things like balance and technique, while routine or automatic movements require fewer attentional resources. Kahneman’s also highlights that attention allocation is really heavily influenced by individual factors like motivation, fatigue and arousal encompasses both the physiological and the  psychological activation and plays a really important role in determining the amount of available attentional capacity. According to Kahneman’s, the central pool, um of available resources is flexible, and this flexibility is influenced by the individual's arousal level. Arousal levels can either enhance or diminish someone's attentional capacity when arousals at its optimal level, attentional resources are maximised, allowing for better performance on tasks. However, if arousal arousal levels are too low or too high, the available attention decreases, often leading to poorer performance theory. ○ Role of Arousal 1. Physiological and psychological alertness 2. Influences breadth and focus 3. Optimal levels vary for different tasks 4. Optimal performance at moderate arousal Multiple Resource theories ○ suggests that attention isn't just a single general pool, but rather several distinct pools that are each tailored for different types of processing. So we get a separate pool for visual tasks, separate pool for auditory auditory tasks and then a separate pool for motor tasks. ○ This means that we can more easily multitask when the tasks are using different types of attention. So people can listen to different types of instructionsbut still perform different types of motor skills.Or people can focus on visual cues while also listening to instructions. ○ Separate Resources Attention divided into specialized 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 ○ more difficult the task or urgent the task, the more attention that it's gonna receive. Resource Availability ○ Limited mental resources ○ We can only allocate the attention if we have the mental energy or the cognitive capacity to do so Practice & Expertise ○ Automaticity with practice ○ with practise tasks often become more automatic, meaning that they require fewer resources and this frees up attention for other activities. Dual-Task Procedures Simultaneous execution of two separate tasks Primary task = the task being assessed for attentional demands Secondary task = additional t