Motor Control and Plasticity

This set of flashcards contains extensive definitions and examples of motor control and the motor pathway. Taken from Behavioral Neuroscience (Breedlove & Watson, 2023), these flashcards were created as a study guide for Exam 3 in Behavioral Neurobiology at BYU-I.

Reflexes

Simple, unvarying responses to sensory stimuli like touch, pressure, and pain

Motor plan (motor program)

A complex set of commands to muscles established before the behavior starts

Electromyography (EMG)

The recording of electrical activity of muscles

Motor control mechanisms generally have to trade _______ for ________, and vice versa

Accuracy, speed

Closed-loop control mechanism

When a control system receives feedback to maximize accuracy

Open-loop control mechanism

A control mechanism in which feedback from system output is not provided to input control, involving ballistic movements

Hierarchy of the motor control system

Skeletal system, spinal cord, brainstem, primary motor cortex, nonprimary motor cortices, cerebellum/basal ganglia

Smooth muscle

Muscle fibers controlled by autonomic nervous system rather than voluntary control, like the heart muscle

Tendons

Tissue connecting muscles to bones

Synergists

Muscles that act together

Antagonists

A muscle that counteract the effect of other muscles (stretches when the other contracts and vice versa)

Motor neurons

Neurons whose axons activate muscle contractions

Two parts of the striated muscle

Myosin and actin

Fast-twitch muscle fibers

Striated muscle fibers that contract rapidly but fatigues readily (running)

Slow-twitch muscle fibers

Striated muscle fibers that contract slowly but don’t fatigue readily (posture, endurance)

Muscular dystrophy (MD)

Degeneration and functional changes in muscles from biochemical abnormalities

Dystrophin

Proteins needed for normal muscle function

Neuromuscular junction (NMJ)

The regions where motor neuron terminals and adjoining muscle fibers meet

Motor unit

A single motor neuron and the muscle fibers it innervates

Innervation ratio

The number of muscle fibers innervated by one motor neuron

Myasthenia gravis

Autoimmune disorder characterized by profound weakness of skeletal muscles that results from loss of acetylcholine receptors

Proprioception

The perception of body movements and positions