Chapter 12

Question 1

vestibular organs

Answer 1

The set of five sense organs (three semicircular canals and two otolith organs) located in each inner ear that sense head motion and head orientation with respect to gravity.

Question 2

spatial orientation

Answer 2

A sense consisting of three interacting modalities: perception of linear motion, angular motion and tilt.

Question 3

vestibular system

Answer 3

The vestibular organs as well as the vestibular neurons in cranial nerve VIII and the centra neurons that contribute to the functional roles that the vestibular system participates in.

Question 4

vertigo

Answer 4

A sensation of rotation or spinning; is often used more generally to mean any form of dizziness.

Question 5

vestibulo-ocular reflex (VOR)

Answer 5

A short-latency reflex that helps stabilize vision by counterrotating the eyes when the vestibular system senses head movement.

Question 6

balance

Answer 6

The neural processes of postural control by which weight is evenly distributed, enabling us to remain upright and stable.

Question 7

kinesthesia

Answer 7

Perception of the position and movement of our limbs in space.

Question 8

active sensing

Answer 8

Sensing that includes self-generated probing of the environment.

Question 9

efferent commands

Answer 9

Information flowing outward from the central nervous system to periphery.

Question 10

afferent signals

Answer 10

Information flowing inward to the central nervous system from sensors in the periphery.

Question 11

graviception

Answer 11

The physiological structures and processes that sense the relative orientation of gravity with respect to the organism.

Question 12

angular motion

Answer 12

Rotational motion like the rotation of a spinning top or wining salon doors that rotate back and forth.

Question 13

linear motion

Answer 13

Translational motion like the predominant movement of a train car or bobblehead doll.

Question 14

tilt

Answer 14

To attain a sloped position like that of the Leaning Tower of Pisa.

Question 15

transduce

Answer 15

To convert from one form of energy to another

Question 16

semicircular canal

Answer 16

Any of three toroidal tubes in the vestibular system that sense angular motion.

Question 17

angular acceleration

Answer 17

The rate of change of angular velocity.

Question 18

otolith organ

Answer 18

Either of two mechanical structures (utricle and saccule) in the vestibular system that sense both linear acceleration and gravity.

Question 19

linear acceleration

Answer 19

The rate of change of linear velocity.

Question 20

sensory conflict

Answer 20

Sensory discrepancies that arise when sensory systems provide conflicting information.

Question 21

sense of angular motion

Answer 21

The perceptual modality that senses rotation.

Question 22

sense of linear motion

Answer 22

The perceptual modality that senses translation.

Question 23

sense of tilt

Answer 23

The perceptual modality that senses head inclination with respect to gravity.

Question 24

amplitude

Answer 24

(vestibular sensation) The size (increase / decrease) of a head movement.

Question 25

direction

Answer 25

The line one moves along or faces, with reference to the point or region one is moving toward or facing.

Question 26

hair cell

Answer 26

Any cell that has stereocilia for transducing mechanical movement in the inner ear into neural activity sent to the brain; some hair cells also receive inputs from the brain.

Question 27

mechanoreceptor

Answer 27

A sensory receptor that responds to mechanical stimulation.

Question 28

receptor potential

Answer 28

A change in voltage across the membrane of a sensory receptor cell in response to stimulation.

Question 29

ampulla

Answer 29

An expansion of each semicircular-canal duct that includes that canal’s cupula, crista, and hair cells, where transduction occurs.

Question 30

crista

Answer 30

Any of the specialized detectors of angular motion located in each semicircular canal in a swelling called the ampula.

Question 31

oscillatory

Answer 31

Referring to back-and-forth movement that has a constant rhythm.

Question 32

sinusoidal

Answer 32

Referring to any oscillation whose waveform is that of a sine curve.

Question 33

Fourier analysis

Answer 33

A mathematical procedure by which any single can be separated into component sine waves at different frequencies. Combining these sine waves will reproduce the original motion trajectory.

Question 34

utricle

Answer 34

One of the two otolith organs; a saclike structure that contains the utricular macula; also called utriculus,

Question 35

saccule

Answer 35

One of the two otolith organs; a saclike structure that contains the saccular macula; also called sacculus.

Question 36

macula

Answer 36

Any of the specialized detectors of linear acceleration and gravity found in each otolith organ.

Question 37

otoconia

Answer 37

Tiny calcium carbonate stones in the ear that provide inertial mass for the otolith organs, enabling them to sense gravity and linear acceleration.

Question 38

velocity storage

Answer 38

Prolongation of a rotational response by the brain beyond the duration of the rotational signal provided to the brain by the semicircular canals; typically yielding responses that are nearer the actual rotational motion than the signal provided by the canals.

Question 39

mathematical integration

Answer 39

Computing an integral.

Question 40

sensory integration

Answer 40

The process of combining different sensory signals. Typically, combining several signals
yields more accurate and/or more pre- cise information than can be obtained from individual sensory signals. This is not the mathematical process of inte- gration learned in calculus (e.g., the integral of acceleration is velocity).

Question 41

vection

Answer 41

An illusory sense of self-motion caused by moving visual cues when one is not, in fact, actually moving.

Question 42

sensory reafference

Answer 42

Change in afference caused by self-generated activity. .

Question 43

sensory exafference

Answer 43

Change in afference caused by external stimuli.

Question 44

autonomic nervous system

Answer 44

The part of the nervous system that is responsible for regulating many involuntary actions and that innervates glands, heart, digestive system, etc.