Chapter 8 - Movement

Question 1

Smooth Muscles

Answer 1

Control the digestive system and other muscles

Question 2

Skeletal (Striated) Muscles

Answer 2

Control movement of the body in relation to the environment

Question 3

Cardiac Muscles

Answer 3

The heart muscles; have properties intermediate between smooth & skeletal muscles.

Question 4

Muscle : Axon Ratio (Eyes, Biceps)

Answer 4

Eyes: (3:1); Biceps (100+:1). Allows the eye to move more precisely than biceps.

Question 5

Neuromuscular Junction

Answer 5

Synapse between a motor neuron axon and muscle fiber.

Question 6

What causes a muscle to contract?

Answer 6

Release of acetylcholine in the neuromuscular junction.

Question 7

What causes a muscle to relax?

Answer 7

Nothing. Muscles relax when there is no message to contract.

Question 8

Antagonistic Muscles

Answer 8

Opposing sets of muscles which cause arms or legs to move in opposite directions.

Question 9

Flexor

Answer 9

Muscles that flex the limb. (i.e. at your elbow, it brings your hand toward your shoulder)

Question 10

Extensor

Answer 10

Muscle that extends a limb. (i.e. at your elbow, it straightens your arm).

Question 11

Fast-twitch fibers

Answer 11

Muscle fibers that contract quickly, and fatigue rapidly

Question 12

Slow-twitch fibers

Answer 12

Muscle fibers that contract less vigorously and do not fatigue.

Question 13

Are slow twitch aerobic or anaerobic?

Answer 13

Aerobic

Question 14

Aerobic

Answer 14

Use oxygen during movements. Does not cause fatigue of muscles.

Question 15

Are fast-twitch aerobic or anaerobic?

Answer 15

Anaerobic

Question 16

Anaerobic

Answer 16

Actions do not require oxygen at the time, but need oxygen for recovery.

Question 17

Proprioceptor

Answer 17

A receptor that detects the position or movement of a part of the body.

Question 18

Stretch Reflex

Answer 18

A reflexive contraction of a muscle in response to the stretch of that muscle. DOES NOT PRODUCE a stretch; it is CAUSED by a stretch.

Question 19

Muscle Spindle

Answer 19

A type of proprioceptor. A receptor parallel to the muscle that responds to a stretch.

Question 20

Golgi tendon organs

Answer 20

A type of proprioceptor. Respond to increase in muscle tension. Act as brakes against excessively vigorous contractions. Located in the tendons at opposite ends of

Question 21

Reflexes

Answer 21

Consistent automatic responses to stimuli.

Question 22

Do we move faster when initiating or responding to stimulus?

Answer 22

We respond

Question 23

Ballistic Movement

Answer 23

A movement executed as a whole. Once initiated, it cannot be altered. (i.e. reflexes)

Question 24

Central pattern generators

Answer 24

Neural mechanisms in the spinal cord that generate rhythmic patterns o motor output. “i.e. wing flapping in birds, and the “wet dog shake”). Although stimuli may activate generators, they do not control the frequency.

Question 25

Motor program

Answer 25

A fixed sequence of movements. (i.e. mouse grooming: sitting up->lick paws->wipe paws over face->close eyes->etc)

Question 26

Primary Motor Cortex

Answer 26

The precentral gyrus of the frontal cortex which elicits movements.

Question 27

Posterior Parietal Cortex

Answer 27

Keeps track of the position of the body relative to the world. (i.e. aim, and planning movements)

Question 28

Supplementary Motor Cortex

Answer 28

Important for planning and organizing a rapid sequence of movements.

Question 29

Premotor Cortex

Answer 29

Most active immediately before a movement. Processes information about target and information about the body’s current position.

Question 30

Prefrontal Cortex

Answer 30

Stores sensory information relevant to a movement. Also important for considering probable outcomes of possible movements.

Question 31

Mirror Neurons

Answer 31

Neurons active during preparation for a movement and while watching someone else perform the same or similar movement.

Question 32

Readiness potential

Answer 32

Recordable activity in the motor cortex prior to voluntary movement

Question 33

Corticospinal Tracts

Answer 33

Paths from the cerebral cortext to the spinal cord

Question 34

Lateral corticospinal tract

Answer 34

Set of axons from the primary motor cortex, surrounding areas, and the red nucleus. Controls movements in peripheral areas (like hands & feet)

Question 35

Red nucleus

Answer 35

Midbrain area responsible for controlling the arm muscles

Question 36

Medial corticospinal tract

Answer 36

Axons from many parts of cortex. Axons go to both sides of spinal cord. Controls muscles of the neck, shoulders & trunk, and movements like walking, turning, bending, standing & sitting. Movement includes both sides of tract.

Question 37

What structure of the brain is responsible mainly for tasks that require timing?

Answer 37

The cerebellum.

Question 38

Which structure in the brain assists in shifting attention?

Answer 38

The cerebellum

Question 39

Cerebellar cortex

Answer 39

The surface of the cerebellum

Question 40

Purkinje cells

Answer 40

Flat cells in sequential planes, parallel to each other

Question 41

Paralell fibers

Answer 41

Axons parallel to one another (perpendicular to Purkinje cells)

Question 42

Basal ganglia

Answer 42

Group of large subcortical structures i nthe forebrain. (Caudate nucleus, putamen, globus pallidus). Critical for initiating an action or learning new habits.

Question 43

Basal ganglia path

Answer 43

Cerebral cortex – > caudate nucleus & putamen –> globus pallidus –> thalamus –> cerebral cortex (motor & prefrontal)

Question 44

Which brain structure(s) aid in automatic motor responses that are difficult to put in words?

Answer 44

Basal ganglia

Question 45

Main symptoms of Parkinson’s Disease

Answer 45

Rigidity, muscle tremors, slow movements, and difficulty initiating physical and mental activity.

Question 46

Population with Parkinson’s

Answer 46

1% - 2% of prople over age 65

Question 47

Cause of Parkinson’s

Answer 47

Impairment of basal ganglia.

Question 48

Main treatment for Parkinsons?

Answer 48

L-dopa

Question 49

L-dopa

Answer 49

Precursor to Parkinson’s which can cross the blood-brain barrier then be converted to dopamine in the brain.