KNES 385 Review for Fall 2024 Final Exam PDF

KNES 385 - Review for Final Exam General information about exam The final exam is comprehensive with a larger emphasis on the most recent material (S1-...

KNES 385 - Review for Final Exam General information about exam The final exam is comprehensive with a larger emphasis on the most recent material (S1-10: ~25%; S12-21: ~30%; S23-29: ~45%). Final exam is on Monday Dec 16; 4:00PM-6:00PM (EST) in the lecture hall TWS 0320. Covers material from session #1 to #29 (both lectures and laboratory materials). Similar format to prior exams: multiple-choice questions (only one answer is correct), true/false questions and open answers. Interpret questions in the most straightforward way possible based on your knowledge of the course material. How to use this extended review: - Use this review to remind yourself of the key topics covered in those lectures. - For any term or topic in this review that you do not fully understand, refer back to the relevant lecture slides and/or labs for examples and additional information to help you understand the term or topic. Fall 2024 Bring your calculator (4-function; Scientific; Graphic are all allowed) and check the battery are charged. RJG © 1 2 Definition and examples – notion of motor control Definition and examples – notion of motor skills Motor skill: Activities or tasks that require voluntary control over movements of the joints and body segments to achieve a goal. Motor control: understanding how our neuromuscular system functions to activate The purpose of a motor skill (or action) is to cause some changes and coordinate the muscles and limbs in the environment or in the person’s relation to the environment. involved in the performance of a (well- known or new) motor skill. An activity is a motor skill if it: Coordination: the patterning of head, 1/ Is directed toward the attainment of a goal (action goal) body and/or limb motions relative to each 2/ Is performed voluntarily other and to the environmental objects 3/ Requires movement of joints and body segments and events. 4/ Has been acquired by experience/practice (learning/re-learning) RJG© RJG© 3 4 1 Definitions and examples – notion of skill level and performance Definition and examples – notion of motor learning Motor learning: changes in the capability of a person to perform a Skill level: Another conceptualization of skill (motor skill) skill; it must be inferred from a relatively permanent improvement relates to some degree of competence to perform a task (i.e.; in performance as a result of practice or experience quality of performance) => notion of expertise. Motor learning emphasized: Criteria to determine an individual’s skill level: Consistent, - Acquisition of motor skills Adaptable, Efficient. - Performance enhancement of learned or highly experienced motor skills - Reacquisition of skills that are difficult to perform - Reacquisition of skills that cannot be performed because of injury or disease Performance: the behavioral act of executing a (motor) skill at a specific time and in a specific situation. Notions of interest when studying motor learning: - Behavioral and/or neurological changes that occur during motor learning - Role of variables influencing motor learning (e.g., types of feedback or practice) RJG© RJG© 5 6 Why differentiate movements, motor skills and neuromotor Definition and examples – notion of movement processes? Movements: Specific patterns of motion among joints and 1/ Motor skills, movements and neuromotor processes represent body segments used to accomplish action goals. the order in which motor control/learning are prioritized. Movements are the component parts of a motor skill to accomplish a goal 2/ Not everyone accomplish the same action goal with the same movement pattern or perform the same movement with the same Definition and examples – notion of neuromotor processes neuromotor processes. Neuromotor processes: mechanisms within the central and peripheral nervous systems as well as the muscular systems that 3/ Distinguish the different levels of study since different measured underlie the control of movements and motor skills. are used to evaluate at the different level Movements and motor skills can be observed by the naked eye but not neuromotor processes (they still can be examined!). RJG© RJG© 7 8 2  Definition and examples – notion of abilities Motor skills: Classifications along a continuum Size of primary musculature required Abilities: An ability is a general trait or capacity of an individual Gross Large & that is a determinant of a person’s achievement potential for the Large muscles small muscles Fine Small muscles performance of specific skills. Walking Shooting arrow Sewing Specificity of beginning and end of action Motor abilities: An ability that is specifically related to the Discrete Serial Continuous performance of a motor skill (e.g., multilimb coordination). Specified beginning Continuous series of discrete Arbitrary beginning and end movements and end ABILITIES SKILLS Flipping light switch Playing piano Walking Relative importance of motor control & cognition Stable Modified by practice Low cognitive Cognition & motor High cognitive demand / Motor control both demand / Motor Inherited traits Developed control maximized important control minimized High jumping Playing quarterback Playing poker Few in number Many in number Stability of the environment Closed Open Underlie performance Depend on different Fixed Changing of many skills subsets of abilities environment environment Walking down empty Walking down hallway in busy RJG© RJG© hallway airport 9 10 & Kinda skipped thou Performance Outcome Measures Magnitude Accuracy Time/speed * Outcome measures: Error measures Dichotomy (hit/miss): Hit or miss of the trials (e.g., target, target center) Absolute error (AE): the unsigned deviation from the target or criterion, representing the amount of error (no regard for direction of deviation). Distance Dichotomy hit/miss Reaction Time Height Zones of accuracy Movement Time Constant error (CE): represents magnitude of error in a specific direction (i.e., it is no longer Weight Absolute error Response Time absolute). It quantifies a bias in performance outcomes. Constant error Variable error (VE): index of how much variability there is in the accuracy of performance. It Variable error is a measure of consistency in performance. The typical measure is the standard deviation. Performance process measures Formulas (will be provided on exam if needed): Ex : error on x-axis Ey : error on y-axis Ci : coordinate of the trial i on a given axis Kinematics Kinetics EMG Brain activity/imaging ∑ : summation N : total number of trial Outcome measures do not tell us how a result was achieved. To CT : coordinate of the target on a given axis understand what underlies performance, we need process measures CM : mean coordinate of all trials on a given axis RJG© RJG© 11 12 3  Mainly Multichoice A written , barely Outcome measures: Error measures * Measures of Time Stimulus Movement Movement Same VE Warning Onset Offset Presentation AE decreases CE moves near 0 AE low AE high CE ≈ 0 Foreperiod RT MT CE < 0 T VE low T Light/color (vision) VE low Response time Word/sound (hearing) Shock/vibration (touch) Same AE & VE Same CE CE changes sign AE & VE increase Reaction time (RT): the interval of time from the onset of a ‘go’ signal or stimulus to the initiation of a response (processing speed) Movement time (MT): the interval from the initiation of the AE high AE high response to the completion of the movement. CE > 0 CE ≈ 0 VE low T VE high T Response time: the sum of RT + MT. From the onset of a ‘go’ stimulus to the completion of the movement. RJG© RJG© 13 14 Not as important Measures of Time Kinematics Simple RT Choice RT Discrimination RT Kinematics: Branch of mechanics that describes the spatial and temporal components of motion (Hamill, 2009) Stimulus Use motion capture system (cameras with/without markers, inertial motion unit, etc.). Response key The kinematics raw data in the form of x, y, and z coordinates allow to derive : Index Index Middle Ring Index - Displacement (linear/angular) - Velocity (linear/angular) - Acceleration (linear/angular) - Jerk/smoothness - Coordination (relative motion) - Others RJG© RJG© 15 16 4  Kinetics m Muscle activity – Electromyography (EMG) Electromyography (EMG): EMG signal represents the summation of all of the Kinetics: Branch of mechanics that deals with the cause of motor unit action potentials that are present at a given time, within the region of motion (Hamill, 2009) muscle from which the electrical activity can be detected (Hug, 2018) (motor unit: a single motor neuron plus all the muscle fibers to which it connects) Examples: Ability to compute the ARV and RMS for the EMG signals as done in the lab - Force: push or pull that can cause objects to positively or 𝑘=𝑁 x(k) : value of a sample at time sample k x(k) : value of a sample at time sample k negativelt accelerate (e.g., push on the ground) (Hamill, ARV = 1 |𝑥(𝑘)| ∑ : summation N : total number of samples RMS = ∑𝑘𝑘 =𝑁 =1 𝑥(𝑘) 2 ∑ : summation N : total number of samples √ |: square root 𝑁 |. | : absolute value 𝑁 2009) 𝑘=1 - Torque: product of force and the perpendicular distance of Surface vs. intramuscular approaches its line of action Reflection of the neural drive activating the muscles Can inform on force, fatigue, coordination Analysis in term of amplitude, timing and frequency Equipment includes force platforms, strain gauges, etc. Some limitations - Inform indirectly the strength of muscle contraction - Fairly low skin conductivity - Crosstalk - Tissue structure RJG© 17 18 * Brain activity - Electroencephalography (EEG) Electroencephalography: electrical patterns (‘brainwaves’) created by the Stepwise movement generation – challenging various stages rhythmic oscillations of neurons. Encode sensory information from Input Stimulus various sources (e.g., vision, balance, Ability to compute EEG power (for a given frequency band) as done in lab. identification body/ limb position). “Make sense of 1 P: power; N: total number of sample; n; current sample; x: the sensory information”. 𝑃= 𝑥 𝑁 EEG value; |.| : absolute value; ∑ : summation Human Response Decision of what response to make Advantages: performer selection (“what to do”) - Directly measure brain activation - Good temporal Resolution - Relatively cheap Movement Prepare the motor system to execute - Easy to transport preparation the movements, skills/actions - Silent! Output (programming) (“how to do it”) - Easy to use for many behavioral paradigm and (Performance) with different populations Limitations: - Limited spatial resolution - Set-up time (depending on the system) RJG© RJG© 19 20 5 D Stepwise movement generation – challenging various stages & Stepwise movement generation – challenging various stages Reaction time (processing information speed) Electromyography (EMG) and reaction time Input Stimulus Movement Movement Warning Presentation Onset Offset Stimulus Stimulus identification Response EMG selection Pre-motor Motor Movement Response preparation key (programming) Index Index Middle Ring Index Middle Ring Pinky Foreperiod Reaction Movement Time Time Output Response time (Performance) RJG© RJG© 21 22 understand-dant need word forward Stepwise movement generation – unfolding the model Input D Sensory, cognitive, motor processing stages Input Encoding various sources of sensory information Integration of the sensory information Encoding various sources of sensory information Integration of the sensory information Combining the various sources of sensory information to create an image of the Executive functions, attention, memory systems body/environment Executive functions, attention, memory systems Inverse kinematics Strategies, decision making, high-level planning Strategies, decision making, high-level planning Motor planning (low-level) Motor programming Motor planning (low-level) Motor programming Spinal cord Inverse dynamics Musculo-skeletal system Spinal cord Sensory Motor inputs inputs Output Input (Performance) Musculo-skeletal system IK: Compute the joint angles to reach a desired end-effector position Feedback ID; Compute the torques/force to produce the desired joint angle Output Input (Performance) RJG© RJG© 23 24 6  General properties of sensory receptors * General properties of sensory receptors Five general properties of sensory receptors: Modality - Adequate stimulus When a specific receptor is stimulated (w/ an adequate stimulus) - Modality to cause a consciously perceived sensation, you get the same - Adaptation modality of sensory experience. - Intensity coding - Receptive field A general class of stimulus, determined by the type of energy transmitted by the stimulus and the receptors specialized to sense Adequate stimulus that energy. The unique stimulus that activates a specific receptor at low Adaptation energy level (roughly speaking, it is the stimulus that “naturally” activates the the decrease in the firing rate of a sensory receptor). neuron in response to a constant stimulus. Most receptors are built to respond only or preferably to one All sensory receptors adapt. kind of stimulus energy (e.g., light is the adequate stimulus for photoreceptors). Adaptation can be fast or slow. RJG© RJG© 25 26 General properties of sensory receptors Visual system Intensity coding Structures: visual pathways from the eyes to the cortex Receptors can detect and code strength or magnitude of the stimulus. Frontal lobe Parietal lobe Graded response: the greater the stimulus the greater the response. - Population coding: The larger number of receptors that are Occipital stimulated, the stronger the perceived stimulus. lobe - Rate coding: A strong stimulus causes receptors to fire at a higher Occipital lobe frequency than a weak stimulus. Monocular/ Receptive field binocular vision The region of a sensory surface (retina, skin, etc.) Temporal lobe that, when stimulated, modulates the activity of a neuron. Brainstem Cerebellum Spatial resolution depends on the number of receptors (density) and size of their receptive fields (e.g., basketball vs. pen). RJG© RJG© 27 28 7  make sure can proved exp If Visual system Processes: Two complementary visual processing pathways Visual system Processes: Monocular vs. binocular vision Ventral (what) pathway: from Binocular vision important for depth perception visual cortex to temporal lobe Binocular vision is important for Responsible for object recognition - Preparation and execution of movement (face, house, tool) - Estimation of distance and size of object Dorsal (where) pathway: - Control of motor skills (e.g., locomotion, object interception) visual cortex to parietal lobe Processes: peripheral and central vision Responsible for object location and movement Role of peripheral and central vision during reach-to-grasp: - Peripheral: assessing environment during transport - Central: become critical as hand is closer to object Clinical example: what and where pathways damage Patients with damage to the inferior temporal area: unable to recognize Role of peripheral and central vision during locomotion: objects, but could reach and grasp the object (visual agnosia) - Peripheral: spatial features of walking environment (optical flow) - Central: guidance for staying on the pathways Patients with damage to the posterior parietal areas have a reduced ability to locate objects (but can recognize) RJG© RJG© 29 30 Visual system Vestibular system Semicircular canals Processes: Perception-action cycle with vision Temporal and spatial coordination between vision and motor: Detect angular acceleration (e.g., Eye-hand; foot-hand coordination) of head Sensory consequences of action and movement regulation Three on each side of head Processes: Processing time of visual information and arranged perpendicular to making movement correction as we move each other Movement can be corrected if there is enough time to process visual information and adjust neural command: - Example of implication for coaching: throwing velocity of the ball Can detect rotation about any - Example of implication for rehabilitation: reaching object fast and slow axis. Y RJG© RJG© 31 32 8  clear it Make sufyour on D Vestibular system Vestibular system Utricle and Sacculus: Pathway to CNS: Vestibulocochlear nerve transmits vestibular information to vestibular nuclei in brainstem. Otoconia To cortex Frontal lobe Parietal lobe Oculomotor nerve Static sensitivity: a change in (controls eye movement) Occipital Vestibulo-ocular reflex position of the head alters the (VOR) lobe pattern of hair cell bending due the Vestibular effect of gravity on the otoliths nuclei To Vestibulocochlear cerebellum Temporal Cerebellum nerve lobe Brainstem Dynamic sensitivity: response to Spinal cord To spinal cord. linear acceleration Contributes to postural control. RJG© RJG© 33 34 Somatosensory system - touch & Somatosensory system - touch Role of cutaneous information in : Fast adapting receptors: - Movement accuracy (e.g., reaching, grasping, playing piano) well-suited to encode info - Movement consistency (e.g., keyboard typing) about change in the ongoing stimulation - Movement timing (e.g., rhythmic movement) - Movement force adjustment (e.g., grip force) Slowly adapting receptors: - Estimate of movement distance (e.g., start/end of movement while touching a surface) well-suited to encode info about spatial attributes of the stimuli (e.g., size, shape) fast slowly fast slowly adapting adapting adapting adapting RJG© RJG© 35 36 9  Somatosensory system - proprioception Somatosensory system - proprioception Muscle Spindle Golgi tendon organ (GTO) Intrafusal muscle fibers only show Located in the myotendinous striations at their ends and therefore can junction only contract in these areas Both passive stretch and active contraction of the muscle There are two types of sensory fibers increases the tension of the that monitor the intrafusal muscle. Both tendon, which activates the GTO. are slow adapting, low threshold MUSCLE TENSION!! mechanoreceptors. The tendon organ (GTO) appears to primary afferent  be more sensitive to active  secondary afferent contraction than to passive stretching. RJG© RJG© 37 38 D Somatosensory system - proprioception Role of proprioception in: A Sensory integration - from physical stimulus to perception Combining sensory modalities (vision, vestibular, somatosensory) - Movement accuracy (e.g., pointing precision, movement amplitude) Primary sensory areas: initial sites for sensory processing (e.g., primary somatosensory cortex, primary visual cortex). - Onset of motor commands (e.g., slower without proprioception) Unimodal sensory association areas: integrate the sensory information - Coordination of body and limb segment for only one sensory modality (e.g., uninodal somatosensory cortex, unimodal visual cortex). + Postural control (e.g., increase sway without biased proprioception) Multimodal sensory association areas: integrate the sensory information + Spatial temporal coupling between limb and limbs segments (e.g., for multiple sensory modalities (e.g., posterior association area - parieto-temporal regions). multijoint reaching movements) Sensory information is processed in series (primary → unimodal → multimodal areas) and in parallel (different information pathways). The posterior parietal cortex (PPC) is involved in: - Elaboration of mental representations (awareness of our own body) - Perception of extrapersonnal space (spatial relationship in the world around us) RJG© RJG© 39 40 10  Beable to explain * All experiments - to Illustrations Executive functions Notion of skill level and performance Classification of skills Executive functions (executive or cognitive control): Refer to a family of top-down mental processes needed when you have to concentrate and pay attention, when going on automatic or relying on instinct or intuition would be ill-advised, insufficient, Cerebellar patient performance assessment Reaching movements under various demands or impossible (Diamond, 2013). Input Encoding various sources of sensory information Three core executive functions: Integration of the sensory information Executive functions, attention, memory systems Strategies, decision making, high-level planning Higher-level executive functions Motor planning (low-level) Motor programming - Inhibitory control Reasoning - Working memory Spinal cord Musculo-skeletal system Problem solving - Cognitive flexibility Output Input (Performance) High-level planning Proprioception and movement control Sensory integration Prefrontal cortex critical for executive functions (not the only one) RJG© RJG© 41 42 High level planning Executive functions - Inhibitory control Executive functions - Working memory Inhibitory control: involves being able to control one’s Working memory: a limited capacity system that operates to attention, behavior, thoughts, and/or emotions to override a temporally store and use recently presented information (Baddley, strong internal predisposition or external lure, and instead do 2003; Magill 2021). what’s more appropriate or needed (Diamond, 2013). An active structure where information is stored for a short time and processed/manipulated Inhibition of: - Thoughts memories (cognitive inhibition) Can store about seven items, plus or minus two items. - Attention (selective or focused attention) - Behavior (self-control) Maintains information for 20-30 seconds before losing parts of information. Examples Encoding of smaller units of information into larger units RJG© RJG© 43 44 11  Executive functions - Cognitive flexibility * Higher order executive functions Cognitive flexibility: Cognitive flexibility is a broad term generally referring to our ability to adapt flexibly to our Reasoning: The ability to reach logical conclusions based on constantly changing environment (Cools, 2015). prior information (Goel, 2017) Ability to change perspectives - Spatially (e.g., Consider a view from a different direction) Problem solving: Problem solving is the process of - Interpersonally (e.g., Consider an issue from another standpoint) constructing and applying mental representations of problems to finding solutions to those problems that are encountered in Ability to change how we think about something nearly every context (Jonassen & Hung, 2012) (e.g., trying various ways to solve a problem) High-level planning: a process that considers actions and their Cognitive flexibility requires and builds on inhibitory control and sequential interdependence in terms of the desirability of their working memory outcomes (Matter & Langyel, 2022) (e.g., find new solutions => need to inhibit familiar solutions and load into the working memory a different one) RJG© RJG© 45 46 Memory systems & Long-term memory – Subsystems Declarative memory Short-term memory: a limited capacity system that temporally Semantic memory: Stores our general knowledge about the world store information (no manipulation). based upon experiences (e.g., conceptual knowledge). Episodic memory: Stores our knowledge about personally experienced events, along with their temporal associations (e.g., allows us to mentally "travel back in time). Long-term memory: A more permanent storage repository of information. Procedural memory: Enables us to know “how to do” something, as opposed to enabling us to know “what to do.” (e.g., riding a bike) Allows people to have information about specific past events as well as general knowledge. Type of knowledge Duration: Generally accepted that the information resides in a Declarative knowledge: Knowledge about what to do in a situation relatively permanent state in long-term memory. that is verbalizable. Capacity: Relatively unlimited capacity for information in long- Procedural knowledge: Knowledge that enables one to actually term memory. perform a skill. Typically, not verbalizable or difficult to verbalize. RJG© RJG© 47 48 12  No need understand forward & word Definition and important concepts Theories - Capacity model Attention: characteristics associated with consciousness, awareness, Central-resource capacity theories of attention: and cognitive effort as they relate to the performance of a skill (Magill Attention-capacity theories that propose one central & Anderson, 2021). source of attentional resources for which all activities Attention: select the most relevant stimuli in the physical world for requiring attention compete. processing while filtering out less relevant information to respond quickly to critical environmental changes and achieve behavioral goals Refers to several characteristics associated with more efficiently (Katsuki & Constantinidis, 2014). perceptual, cognitive, and motor activities that establish Concept 1: humans have a limited limits to our performance of motor skills. availability of resources for performing tasks and gaining information Fixed and flexible models Concept 2: environmental information must be reduced or filtered RJG© RJG© 49 50 *Theories – Capacity model Fixed capacity models Beginner Driving the car - steering, Theories – Capacity model Flexible capacity models braking, signaling, etc… Tasks Attention capacity should not be considered fixed as task Monitoring other cars requirements change (Kahneman, 1973) Monitoring position on road Talking to passengers Irrelevant info Available attention that can be given to a task is a pool of effort. This can be distributed to several activities at once. Expert Miscellaneous Driving the car Monitoring position on road Talking to passengers Arousal becomes a factor. Single, fixed capacity Monitoring road position channel Monitoring upcoming stoplight Deciding to pass RJG© RJG© 51 52 Like being Freshman to Senior Campus on 13 D & Top-down and bottom-up attentional processes Top-down and bottom-up attentional processes Top-down (or endogenous) attention: an internally induced Visual search influences three aspects of the action control process in which information is actively sought out in the process. environment based on voluntarily chosen factors (Katsuki - Action selection & Constantinidis, 2014). - Constraining of the selected action - Timing of action initiation Visual search is the process of actively directing visual Bottom-up (or exogenous) attention: an externally induced attention to locate relevant information in the environment. process in which information to be processed is selected automatically because of highly noticeable features of Evidence that eye movements (central vision) directed to a stimuli (Katsuki & Constantinidis, 2014). location are preceded by a shift in attention to that area Any sensory modality could be involved in bottom-up or => coupling attention and eye movements top-down attentional processes RJG© RJG© 53 54 D D Attentional focus Attention and automaticity Attentional focus: The directing of attention to specific Automaticity: Performance of a skill (or its parts) with aspects of our performance or performance environment. little/no demand on attention capacity. Width: Focus can be broad or narrow -orget Relates to evaluation of the task demands in the component Direction: can be external or internal of Kahneman’s model of attention. it - Internal focus: focus of attention on one’s own movement - External focus: focus of attention on the effects of one’s own movement Some problems require various levels of effortful mental activities (also influenced by experience/practice). Switching: changing focus Brain dynamics and automaticity RJG© RJG© 55 56 14 & Measurement of attention & From the sensory to the motor side The dual task paradigm Input Sensory integration (internal Determines attention demands and characteristics of the Encoding various sources of sensory information Integration of the sensory information representations) simultaneous performance of two different tasks Executive functions, attention, memory systems Strategies, decision making, high-level planning Motor areas Primary task is the task of interest Motor planning (low-level) (Motor planning, programming) Motor programming Secondary task (distractor) performance allows to make Spinal cord inferences about attention demands of the primary task Musculo-skeletal system Motor Sensory Output outputs inputs Input (Performance) Limitation of the paradigm Motor associative areas (high-level planning, EEG correlates of attention strategies, goals, etc.) - RJG© RJG© 57 58 Need to know-put in a relelsitiation Like a patient Schematic overview of the motor system D Cortical regions - prefrontal cortex Higher center (PFC) The prefrontal cortex (PFC) is involved in information processing with a high level of integration. Descending Systems LPMC and SMA Basal Ganglia The PFC plays an important role in: Motor Cortex - Executive functions (e.g., inhibitory control, working Cerebellum memory) Motor outputs - Select appropriate response Local circuit neurons Motor Neuron pools - Anticipation of action consequences Spinal Cord and Brainstem Circuits - Sequencing of behavior over time Sensory Inputs Skeletal Muscles RJG© RJG© 59 60 Gives good overview prefrontal to primary motor Cortex 15 ↑ * Cortical regions - premotor cortex Cortical regions - primary motor cortex The premotor cortex (PMC, area 6) includes: - The Lateral Premotor Cortex (LPMC) The primary motor cortex (area 4) : - The Supplementary Motor Area (SMA). - Controls a group of muscles to move an entire segment towards an objective The PMC is involved in : - Eliciting complex movements (multijoints motion; hand shaping) - Elicit simple movements of single joints - Contributing to specify motion features - Is active before movement onset and stay actives during the The PMC receives inputs from the Basal Ganglia and the Cerebellum entire movement. (via the thalamus) - It encodes the movement direction and the force produced to All premotor areas project to the spinal cord (but less than the perform the movement. primary motor area) Cross-over and contralateral movements RJG© RJG© 61 62 · know whats happening D Motor planning and programming Basal Ganglia - structure Motor planning: The structure of Basal Ganglia : - Distributed process involving various brain regions - Mainly PFC, SMA, LPMC (modulated by the Basal Ganglia - Striatum (Caudate nucleus + Putamen) and the Cerebellum!) - Globus pallidus - Select the appropriate motor plans A. Motor Planning B. Motor Program - Substantia Nigra - Subthalamic Nucleus Motor programming: - Distributed process involving various brain regions - Mainly the premotor (e.g., SMA, LPMC) and primary motor areas (modulated by the Basal Ganglia and the Cerebellum!) - Implement the movement plan (e.g., movement amplitude, direction, force). The Basal Ganglia have access to the cortical somatotopy RJG© RJG© 63 64 16 & # understand functi Basal Ganglia - functions Cerebellum – inputs and outputs Basal Ganglia are involved in: Inputs - The choice of the right strategy/motor plans Serves as a multisensorial - Activates & retrieves movement plans integrator (visual, auditory, proprioceptive, vestibular - Movement initiation & completion (activated before movement onset) information) - Scales movement parameters (power, speed, direction, amplitude) - Sequencing information From the spinocerebellar tracts (non-conscious Serial processing throughout the Basal Ganglia - Thalamo proprioception; fast cortical loop (cortex is activated first) conduction speed) The Basal Ganglia do not have direct input or output to the spinal cord RJG© RJG© 65 66 D Cerebellum – inputs and outputs Cerebellum - functions Outputs Muscle tone & ongoing The Cerebellum is involved in: execution of movement Axial, proximal, distal muscles - Spatial accuracy (e.g., pointing) and timing (e.g., coordination) of the movement Timing & Coordination of - Balance and muscle tone skilled movement - Motor control and learning as well as some cognitive functions - Anticipatory computation of the muscular commands (e.g., account for the mechanical effects on the effectors) Posture & The Cerebellum does not project directly to the spinal cord Equilibrium RJG© RJG© 67 68 17 * Cerebellum - functions Feedforward (open-loop) and feedback (closed-loop) control The Cerebellum influences the motor systems by: Open-loop control system: a system of control in which, during the - Evaluating disparities between intentions and action course of an action, sensory information related to the effects of - Adjusting the operation of motor centers in the cortex and brainstem motor commands does not affect future motor commands. during: Movement Motor Commands Muscles, Body o Movement in progress (online control) Control Center & Environment o Repetition of the same movement (learning) The Cerebellum: Closed-loop control system: a system of control in which, during the - Receives many information about the goals, commands and feedback course of an action, sensory information related to the effects of signals associated with the movement preparation and execution motor commands can affect future motor commands. Movement Motor Commands Muscles, Body - Projects mainly to the premotor, motor centers, brainstem (that controls spinal interneurons and motor neurons directly) Control Center & Environment - Is critical for motor learning Sensory Feedback The movement control center is part of the CNS. RJG© RJG© 69 70 Feedforward (open-loop) control Feedforward (open-loop) control and motor program theory Input Feedforward control and pre-planned/programmed responses Encoding various sources of sensory information A motor program is a pre-structured set of motor commands Movement Integration of the sensory information selected by the CNS and sent to the peripheral nervous system Control Center Executive functions, attention, memory systems The concept of a motor program is rooted in information processing and the computer analogy Motor Commands Strategies, decision making, high-level planning Motor planning (low-level) How might you be able to infer that a pre-structured set of Motor programming ‘ commands ’ are the critical information guiding a movement? Spinal cord - Evidence for motor control in the absence of feedback Muscles, Body Musculo-skeletal system - Evidence for motor control in absence of sensory delay & Environment - Longer processing for complex movements Output (Performance) RJG© RJG© 71 72 18  Skip same in being Feedback (closed-loop) control Definition and examples – notion of motor learning Input Motor learning: changes in the capability of a person to perform a skill; it must be inferred from a relatively permanent improvement Encoding various sources of sensory information in performance as a result of practice or experience Movement Integration of the sensory information Control Center Executive functions, attention, memory systems Motor learning emphasized: Motor Commands Strategies, decision making, high-level planning - Acquisition of motor skills - Performance enhancement of learned or highly experienced motor skills Motor planning (low-level) - Reacquisition of skills that are difficult to perform Motor programming - Reacquisition of skills that cannot be performed because of injury or disease Spinal cord Muscles, Body Musculo-skeletal system Notions of interest when studying motor learning: & Environment - Behavioral and/or neurological changes that occur during motor learning Output (Performance) - Role of variables influencing motor learning (e.g., types of feedback or practice) RJG© RJG© 73 74 Neural systems and motor learning Neural systems and motor learning Relationship between learning and memory - Learning is the process of acquiring new information All levels of the CNS contribute to motor learning including the - A memory is created when something new is learned lowest in its hierarchy (e.g., spinal cord, brainstem). - A memory is c