Motor Control Flashcards

Flashcards about Motor Control for Physical Therapy

Motor Control

The underlying substrates of neural, physical, and behavioral processes that govern posture and movement.

Processes for motor control

Includes motor, cognitive, and perceptual development

Neural circuits crucial for Motor Control

Cortex, brainstem, cerebellum, and spinal cord

Motor Plan

Limb – the effector of the output of the neural circuit

Goal

Movements are _ oriented

Sensory forward model

Mapped to a set of predicted sensory outcomes referred to as the _.

Nervous and Muscular

Movement emerges as the _ and _ systems mature.

Motor control time frame

Happens in fractions of seconds.

Neurologic dysfunction

The correct movement pattern but having impaired timing, producing the movement too slowly to be functional; or impaired sequencing of muscle activation, producing a muscle contraction at the wrong time.

Reflexive

Sensation cues _ movements.

Sensation

Provides feedback accuracy.

Feedback

Defined as sensory or perceptual information received as a result of movement

Intrinsic feedback

Any sensory source inside the body, such as from proprioceptors, or outside the body; based on sensory responses inherent to the patient's body as part of the desired movement itself.

Extrinsic feedback

Based on an outside source providing feedback; extra or augmented sensory information given to the mover by some external source.

Knowledge-of-performance feedback

Uses a sensory system (such as the therapist's voice) to inform the patient as to whether the quality or efficiency of the movement pattern is achieved

Knowledge-of-results feedback

Informs the patient as to whether the task is accomplished or how close the movement comes to accomplishing the task.

Summary feedback

When the feedback is given after a set number of trials of the task.

Faded feedback

Initially provides feedback after every trial, then decreases to every other trial, every third, every fourth, and so on.

Delayed feedback

Clinician withholds the feedback for a short time (eg, a 5-second delay) after the task has been performed.

Ascending

Sensory information (feedback) is transmitted in _ pathways to higher centers.

Closed-loop system

Type of system control involving feedback, error detection, and error correction that is applicable to maintaining a system goal.

Open loop system

Type of system control in which instructions for the effector system are determined in advance and run off without feedback.

Feedforward

Anticipated sensory consequences of movement that should occur if the movement is correct; sending of signals in advance of movement readies the sensorimotor systems and allows for proactive (anticipatory) adjustments in postural activity.

Primitive Reflexes

Occur early in the lifespan of the infant, not because they are not sophisticated.

Integration

Mechanism by which less mature responses are incorporated into voluntary movement

Righting reactions

Sensory information to orient the head in space and the body relative to the head and the support surface.

Equilibrium reactions:

Complex postural responses that respond to slow balance disturbances; continue to be present into adulthood.

Protective reactions:

Extremity movements in response to quick displacements of the center of gravity out of the base of support

Mobility

Initial random movements are _.

Stability

Maintenance of a posture.

Controlled Mobility

Movement within a posture.

Skill

Movement from one posture to another posture.

Mobility stage

Exhibits random movements within an available range of motion for the first 3 months of development.

Stability stage

The ability to maintain a steady position in a weight-bearing, antigravity posture; also called static postural control.

Tonic holding

Occurs at the end of the shortened range of movement and usually involves isometric movements of antigravity postural extensors

Co-contraction

Simultaneous static contraction of antagonistic muscles around a joint to provide stability in a midline position or in weight bearing.

Controlled mobility

Mobility superimposed on previously developed postural stability by moving within a posture.

Skill

Most mature type of movement, usually mastered after controlled mobility within a posture; mobility is superimposed on stability in non–weight bearing; proximal segments stabilize while distal segments are free for movement.

Postural control

The ability to maintain the alignment of the body, alignment of body parts relative to each other and the external environment

Righting reactions

Responsible for orienting the head in space and keeping the eyes and mouth horizontal.

Protective reactions

Extremity movements that occur in response to rapid displacement of the body by diagonal or horizontal forces

Equilibrium reactions

Allow the body as a whole to adapt to slow changes in the relationship of the center of mass with the base of support.

Motor program model of motor control

Developed to challenge the notion that all movements are generated through chaining or reflexes because even slow movements occur too fast for sensory input to influence them.

Motor program

May also refer to a specific neural circuit called a central pattern generator (CPG), which is capable of producing a motor pattern, such as walking.

Systems model of motor control

Currently used to describe the relationship of various brain and spinal centers working together to control posture and movement; neural control of posture and movement is distributed.

Closed-loop model of motor control

Sensory information is used as feedback to the nervous system to provide assistance with the next action

Open-loop model of motor control

Movement is cued either by a central structure, such as a motor program, or by sensory information from the periphery; movement is performed without feedback.

Postural control

Relationship between posture and movement; readiness to move, an ability not only to react to threats to balance but also to anticipate postural needs to support a motor plan

Components of the postural control system

Identified as part of a postural control system: limits of stability, sensory organization, eye-head stabilization, the musculoskeletal system, motor coordination, predictive central set, and environmental adaptation

Limits of stability

The boundaries of the base of support (BOS) of any given posture; if the center of mass (COM) is within the base of support, the person is stable

Sensory organization

Visual, vestibular, and somatosensory systems provide the body with information about movement and cue postural responses

Somatosensation

Combined input from touch and proprioception.

Eye-head stabilization

Eyes and labyrinths: two of the most influential sensory receptors for posture and balance in the head

Musculoskeletal system

Mechanically linked structure that supports posture and provides a postural response; viscoelastic properties of the muscles, joints, tendons, and ligaments can act as constraints to posture and movement

Muscle tone

Defined as the resting tension in the muscle and the stiffness in the muscle as it resists being lengthened.

Motor coordination

Ability to coordinate muscle activation in a sequence that preserves posture.

Predictive central set

Component of postural control that can best be described as postural readiness

Environmental adaptation

Posture and movement adapt to the environment in which the movement takes place

Nashner’s model of postural control in standing

Ankle strategy, the hip strategy, and the stepping strategy

Degrees of freedom

number of planes of motion possible at a single joint.

Motor learning

The process that brings about a permanent change in motor performance as a result of practice or experience

Adams’s theory of motor learning

Base on closed-loop control; sensory feedback from ongoing movement is compared with stored memory of the intended movement (perceptual trace) to provide the CNS with a reference of correctness and error detection

Schema

A rule, concept, or relationship formed based on experience.

Novice stage

Initial stage of motor learning, the learner reduces the degrees of freedom that need to be controlled during the task; learner will “fix” some joints so that motion does not take place and the degree of freedom is constrained at that joint.

Advanced stage

Learner allows more joints to participate in the task, releasing some of the degrees of freedom. Coordination is improved as agonist and antagonist muscles around the joint work together to produce movement, rather than co-contracting to “fix” the joint in earlier movement attempts

Expert stage

When all degrees of freedom necessary to perform a task in an efficient, coordinated manner are released; learner can begin to adjust performance to improve the efficiency of the movement by adjusting the speed of the movement

Massed practice

Greater practice time than rest time occurs in the session; opportunity for the patient to repetitively practice a motor pattern or functional movement with few interruptions

Distributed practice

Amount of rest time is longer than the time spent practicing; used when the patient has acquired a motor memory of the task, but impairment errors occur and practice is still needed to ensure long- term motor memory

Blocked practice

The same task is repeated several times in a row; one task is practiced several times before a second task is practiced

Random practice

When a variety of tasks is practiced in a random order, with any one skill rarely practiced two times in a row

Constant Practice

Individual practices one variation of a movement skill several times in a row

Variable practice:

The learner practices several variations of a motor skill during a practice session

Whole task practice

Task can be practiced as a complete action; refers to practicing a behavior or task in its entirety.

Part Practice

Task broken up into its component parts.

Whole learning

Motor program is practice as a whole. Whole learning should be taught for simple programs, such as rolling over, coming to sit, coming to stand, and walking.

Open and closed tasks

Movement results when an interaction exists among the mover, the task, and the environment; task to be learned can be classified as either open or closed

Open tasks

Done in environments that change over time such as playing softball, walking on different uneven surfaces, or driving a car

Closed tasks

Skills that have set parameters and stay the same, such as walking on carpet, holding an object, or reaching for a target

OPTIMAL theory

Stands for optimizing performance through intrinsic motivation and attention for learning; theory assumes that attention and motivation (social-cognitive and affective) influence motor learning behavior

Neuroplasticity

Defined as cellular adaptations in the CNS that allow an individual to learn novel skills or relearn functions previously lost because of cellular death by trauma or disease at any age

Use it or lose it

Movements and functional patterns that are not performed or practiced are lost, including the motor circuitry responsible for that movement in the CNS

Use it and improve it

It is not sufficient to just encourage use of the affected extremity. Specific training to improve function on that limb consequently drives the changes in the brain that reinforce this improvement.

Specificity

The training to improve function has to be specific.

Saliency matters

The chosen activity being practiced must be meaningful for the patient.

Repetition and intensity matter

Most recent research on this topic clearly shows that the intensity of therapy that we currently provide the majority of our patients/clients is not sufficient to drive these changes

Cognitive Stage of Motor Learning

Learner consciously has to consider the goal of the task to be completed and recognize the features of the environment to which the movement must conform.

Associative stage of Motor Learning

Learner practices and refines the motor patterns, making subtle adjustments. Spatial and temporal organization increases while errors and extraneous movements decrease

Autonomous phase of Motor Learning

Continues to practice and refine motor patterns; spatial and temporal components of movement become highly organized over time with extensive periods of practice

Kleim and Jones suggested principles (based on research on neuroplasticity)

Use it or lose it, Use it and improve it, Specificity, Saliency matters, Repetition and intensity matter