Chapter 8 - The Sensorimotor System

Question 1

Sensory feedback

Answer 1

Sensory signals that are produced by a response and are often used to guide the continuation of the response

Question 2

Posterior parietal association cortex

Answer 2

An area of association cortex that receives input from the visual, auditory, and somatosensory systems and is involved in the perception of spatial location and guidance of voluntary behavior

Question 3

Frontal eye field

Answer 3

A small area of prefrontal cortex that controls eye movements

Question 4

Action map

Answer 4

A mental representation of the world or some part of it based on subjective perceptions rather than objective geographical knowledge

(via APA Dictionary of Pyschology)

pg.222 in the book

Question 5

Astereognosia

Answer 5

An inability to recognize objects by touch that is not attributable to a simple sensory deficit or to an intellectual impairment

Question 6

Movement vigor

Answer 6

The control of the speed and amplitude of movement based on motivational factors

Question 7

Motor units

Answer 7

A single motor neuron and all of the skeletal muscle fibers that are innervated by it

Question 8

Motor end-plate

Answer 8

The receptive area on a muscle fiber at a neuromuscular junction

Question 9

Motor pool

Answer 9

All of the motor neurons that innervate the fibers of a given muscle

Question 10

Flexors

Answer 10

Muscles that act to bend or flex a joint

Question 11

Extensors

Answer 11

Muscles that act to straighten or extend a joint

Question 12

Apraxia

Answer 12

A disorder in which patients have great difficulty performing movements when asked to do so out of context but can readily perform them spontaneously in natural situations

Question 13

Contralateral neglect

Answer 13

A disturbance of the patient’s ability to respond to stimuli on the side of the body opposite to a site of brain damage, usually the left side of the body following damage to the right parietal lobe

Question 14

Dorsolateral prefrontal association cortex

Answer 14

An area of the prefrontal cortex that plays a role in the evaluation of external stimuli and the initiation of complex voluntary motor responses

Question 15

Secondary motor cortex

Answer 15

An area of the cerebral cortex that receives much of its input from association cortex and sends much of its output to primary motor cortex

Question 16

Supplementary motor area

Answer 16

The area of secondary motor cortex that is within and adjacent to the longitudinal fissure

Question 17

Synergistic muscles

Answer 17

Pairs of muscles whose contraction produces a movement in the same direction

Question 18

Antagonistic muscles

Answer 18

Pairs of muscles that act in opposition

Question 19

Isometric contraction

Answer 19

Contraction of a muscle that increases the force of its pull but does not shorten the muscle

Question 20

Dynamic contraction

Answer 20

Contraction of a muscle that causes the muscle to shorten

Question 21

Golgi tendon organs

Answer 21

Receptors that are embedded in tendons and are sensitive to the amount of tension in the skeletal muscles to which their tendons are attached

Question 22

Muscle spindles

Answer 22

Receptors that are embedded in skeletal muscle tissue and are sensitive to changes in muscle length

Question 23

Intrafusal muscle

Answer 23

A threadlike muscle that adjusts the tension on a muscle spindle

Question 24

Intrafusal motor neuron

Answer 24

A motor neuron that innervates an intrafusal muscle

Question 25

Skeletal muscle (extrafusal muscle)

Answer 25

Striated muscle that is attached to the skeleton and is usually under voluntary control

Question 26

Patellar tendon reflex

Answer 26

The stretch reflex that is elicited when the patellar tendon is struck

Question 27

Stretch reflex

Answer 27

A reflexive counteracting reaction to an unanticipated external stretching force on a muscle

Question 28

Premotor cortex

Answer 28

The area of the secondary motor cortex that lies between the supplementary motor area and the lateral fissure

Question 29

Mirror neurons

Answer 29

Neurons that fire when an individual performs a particular goal-directed hand movement or when they observe the same goal-directed movement performed by another

Question 30

Primary motor cortex

Answer 30

The cortex of the precentral gyrus, which is the major point of departure for motor signals descending from the cerebral cortex into lower levels of the sensorimotor system

Question 31

Somatotopic

Answer 31

Organized, like the primary somatosensory cortex, according to a map of the surface of the body

Question 32

Motor homunculus

Answer 32

The somatotopic map of the human primary motor cortex

Question 33

Stereognosis

Answer 33

The process of identifying objects by touch

Question 34

Spindle afferent neurons

Answer 34

Neurons that carry signals from muscle spindles into the spinal cord via the dorsal root

Question 35

Withdrawal reflex

Answer 35

The reflexive withdrawal of a limb when it comes in contact with a painful stimulus

Question 36

Reciprocal innervation

Answer 36

The principle of spinal cord circuitry that causes a muscle to automatically relax when a muscle that is antagonistic to it contracts

Question 37

Cocontraction

Answer 37

The simultaneous contraction of antagonistic muscles

Question 38

Recurrent collateral inhibition

Answer 38

The inhibition of a neuron that is produced by its own activity via a collateral branch of its axon and an inhibitory interneuron

Question 39

Central sensorimotor programs

Answer 39

Patterns of activity that are programmed into the sensorimotor system

Question 40

Motor equivalence

Answer 40

The ability of the sensorimotor system to carry out the same basic movement in different ways that involve different muscle

Question 41

Response-chunking hypothesis

Answer 41

The idea that practice combines the central sensorimotor programs that control individual responses into programs that control sequences (chunks) of behavior