MOTOR BEHAVIOR - EXAM 2

exam on 10/8

an open-loop control system relies on feedback to continue and terminate movement

false

which area of the brain controls our feedback loop?

cerebellum

motor program based theories highlight environmental influence on the mechanical properties of the body and limbs

false

why are motor behavior theories important for the practitioner?

• help identify motor skill performance problems

• can help develop intervention strategies in rehabilitation

• can help evaluate the effectiveness of a chosen intervention program

• can help predict which intervention program would produce the best outcome for learning and re-learning motor skills

continuous motor skills require closed loop control systems

true

invariant features are the signature of a generalized motor program (GMP) and form the basis of what is stored in memory

true

stable states of a system are never dysfunctional

false

which brain lobe is most responsible for the perception and integration of sensory information?

parietal

according to the dynamical systems theory, invariant features are the stable behavioral steady states of the system

false

control parameters are variables, when increased or decreased, can assess the stability of an order parameter

true

what are all aspects of the degree of freedom (DOF) problem?

• synergies

• mechanics

• efficiency

• coordination

efficiency refers to performing the task with an economy of effort

true

according to fitts law, the higher the index of difficulty (ID) the easier the task is

false

which one performer (individual) characteristic that will influence reaction time (RT) according to hicks law?

alertness

muscle spindles are located in the insertion tendon of muscle detect changes in muscle tension

false

mental practice is the act of engaging in visual or kinesthetic imagery

true

what are examples of a constraint-led approach to coaching kid’s football?

• having children play on smaller, size-regulated fields scaled to the player’s age/height/affordances

• adjusting the rules/regulations during performance that are age appropriate

• practicing game-like drills during practice and focusing on limitations the children face

• advancing their skill techniques and progressing play from touch > flag > tackle football respectfully as the kids get older

the mountain of motor development states we will all become skillful at some point during our lifespan

false

regulatory conditions in the environmental context of performance situations are invariant, and therefor act as affordances for movement

true

you don’t need to become proficient in fundamental motor skills in order to pass the proficiency barrier

false

constraints on movement don’t interact, making it easy for practitioners to distinguish them from one another

false

what are examples of a functional constraint?

• cognitive ability

• motivation

• fatigue

according to bernstein, “freeing the DOF” allows for restrictive joint movements to reduce complexity

false

i am afraid to walk outside on uneven/un-supporting surfaces while it’s raining because I am afraid of falling

this is an example of a(n) _____ affordance

subjective

the _____ system forms the foundation for the control of movement

neuromotor

dendrites

receive information

axons

send information - there is only ONE per nerve

sensory (afferent)

peripheral nerves

motor (efferent)

peripheral nerves

inter-neurons

specialized neurons that originate and terminate in the brain and/o spinal cord

sensory (afferent) neurons

send neural impulses to the central nervous system (cns)

what type of tracks do sensory neurons have

ascending

motor (efferent) neurons

collect neural impulses from the cns

what type of tracks to motor neurons have

descending

alpha motor neurons

found in the spinal cord and collect directly with skeletal muscle fibers

gamma motor neurons

supply a portion of the skeletal muscle and are called intrafusal fibers

henneman’s size principal

number of fibers active at any one time influences the amount of force a muscle can exert

increased force mean _____ numbers

increased

four structures

are most directly involved in movement control

cerebrum

four lobes - largest part of the brain

diencephalon

controls attention, mood, and perception of pain

brainstem

integration of sensory and motor neural impulses. inhibits and activates cns to influence skeletal muscle activity

cerebellum

stands alone - smallest part of brain

cerebrum

two halves connected by corpus callosum

attention

the pre-requisite for information processing for movement

primary motor cortex

anterior to central sulcus

premotor area (cortex)

anterior to primary motor cortex

supplementary motor area (cortex)

located on the medial surface of the frontal lobe

primary motor cortex

• contains motor neurons connecting to specific skeletal muscles throughout the body

• critical for movement initiation and coordination of movements for fine motor skills

• involved in the control and learning of postural coordination

supplementary motor area (corext) (sma)

• controls organization of movements before they are initiated and rhythmic coordination during movement

• enables transitions between sequential movements of a learned serial motor skill (typing sentences or playing the piano)

• essential for bimanual coordination

premotor area (cortex)

• plays essential role in planning movements based on external sensory information (environmental context/action preparation)

parietal lobe

interacts with premotor cortex and primary motor cortex before and during movement

temporal lobe

speech and language center

• plays important roles in memory, abstract thought, and judgement

• most strokes affect temporal lobe and speech

occipital lobe

visual information processing

basal ganglia

buried deep within the central hemispheres

• aids in planning and imitation of movement

• controls antagonist muscles during movement

• aids in force control

• parkinson’s disease is associated with dysfunction of basal ganglia dur to lack of dopamine production

cerebellum

• responsible for feedback loop we use to learn motor skills

• involved in control of smooth and accurate movements

• serves as movement error detection and correction system

• active in control of hand-eye coordination, movement timing, force control, and postural control 

• receives efference copy of motor neural signals sent from the motor cortex to the muscles 

what makes a theory

definite predictions about the result of future observations

motor learning and control theories focus on

• explaining human motor behavior

• providing explanations about why people perform skills and learn skills as they do

motor control theory

explains how the nervous system produces coordination movements to successfully perform a variety of motor skills in a variety of environmental context

coordination

the patterning of head, body, and limb movements relative to the patterning of environmental objects and events

skill

performance coordination

environmental

influence coordination

control center (executive)

• generates forward movement instruction to effectors

• do not always use feedback (sensory information)

open loop

does NOT use feedback

• all movement information necessary to complete the action goal is sent to effectors and carried out

closed loop

uses feedback: afferent information sent by various sensory receptors to control center

• more complex human movements

• control center sends information to effectors only to initiate movement

sensory feedback

needed to continue and terminate movement

motor program

based construct that controls coordinated movement

dynamical systems

emphasizes the role of information in the environment and mechanical properties of body and limbs

motor program

a memory representation that stores information needed to perform an action

• memory storage process

• retrieval process

• movement coordination patters

richard schmidt

proposed we use the executive center to generate movement through cognition and memory

generalized motor program (gmp)

each controls a class of actions, which are identified by common invariant features

invariant features and fixed characteristics

• this is the signature of a gmp and form the foundation/basis of what is stored in memory

• characteristics that do not vary across performances of a skill within a class of action

example of invariant features

relative time (percentage) spent on task completion, sequence of actions used to achieve action goal

example of movement parameters

absolute duration (time), force of muscles used, which muscles are used

schema

a rule or a set of rules serves to provide a basis for a decision

schmidt’s schema theory

helps explain how the gmp operates to control coordinated movements

gmp

responsible for controlling movement coordinated patterns for a class of actions (invariant features)

motor response schema

provides specific rules governing the performance of a skill within any situation (movement patterns)

dynamical systems theory

describes the control of coordinated movement by emphasizing the role of environmental information and dynamical properties of the body and limbs

researchers view the process of human development and movement control as a complex system

• identifies laws for understanding how a system evolves/changes over time for one stable state to another due to a particular variable influence

• motor development plays a large aspect of dynamical systems theories as well as motor control

non-linear dynamics

• behavioral changes over time do not follow a continuous, linear progression; but make sudden abrupt changes

• distinct coordination patterns can spontaneously develop as a function of a change in a specific variable (speed)

kelso experiments

linear increase in movement speed led to nonlinear change in the fundamental pattern of movement 

stability

according to dynamics, _____ is the behavioral steady state of a system

stability

_____ means that even when something slightly throws the system off, it naturally (spontaneously) goes back to its stable state - this shows that some variability is normal and even helpful

attractors

the stable behavioral steady states of a system

• preferred behavioral states (preferred coordination patterns)

• stable regions of operation 

• energy efficient

order parameters

• functionally specific variables that define the overall behavior of a system; they define a movement pattern

• enables one coordinated pattern of movement to be distinguished from other movement pattern

• relative phase is the most prominent order parameter

control parameters

• variables, when increased or decreased, will influence the stability of the order parameter

• variables of manipulation to challenge stability of an order parameter

• by assessing the stability, we can shift a coordination pattern from one stable state to another

self-organization

• a movement behavior that spontaneously emerges in response to a particular set of constraints

• coordination patterns self-organizes due to environmental conditions, task demands, and limb dynamics

coordinative structures

• groups of muscles (and joints) constrained to act as functional units by the nervous system to act cooperatively to produce an action

• muscles/joints work together to enable success

• if a perturbation stops a muscles synergy from working (injury) another automatically compensates (self-organization)

intrinsic coordinative structures

• involve actions such as walking, running, and bimanual coordination

• symmetrical movements 

• can lead to inital performance difficulties for some action goals

coordinative structures

• developed through practice are new combinations of muscles and joints acting together to enable success

• we must override intrinsic structures to develop new structures through practice/opportunities/experience

perception-action coupling

refers to the continuous and dynamic relationship between perception and action; where out senses inform our movements and our movements alter our perceptions

• perception informs action

• action changes perception

• feedback loop

• adaption and interaction with surroundings (environment)

degree of freedom problem

in biomechanics is the number of independent ways a system (body) can move or vary without violating any constraints

dof gives us an opportunity to ____ to constant changing environmental situations

adapt

early development

first learning a skill

development throughout the lifespan

injuries, aging, re-learning

nikolai bernstein

formulated dof problem

• the problem results from infinite redundancy, yet flexibility between movements; thus, the nervous system must choose a particular motor solution every time it acts

acquisition

the process of mastering redundant dof

complex movement coordination

neuromuscular control

changes associated with learning

including neural plasticity