Chapter 12 (Psy 323)

Question 0

What are the semicircular canals?

Answer 0

They are the three toroidal tubes in the vestibular system that sense angular motion.

Question 1

What are the otolith organs?

Answer 1

They are the mechanical structures in the vestibular system that sense both linear acceleration and gravity. Each otolith organ contains an utricle, a saccule, and maculae.

Question 2

What are the three axes of movement coded by the vestibular system?

Answer 2

x-axis: The axis of motion forward and backward
y-axis: The axis of motion leftward and rightward
z-axis: The axis of motion upward and downward

Question 3

What are the three directions of rotation coded by the vestibular system?

Answer 3

Roll: Rotation around the x-axis
Pitch: Rotation around the y-axis
Yaw: Rotation around the z-axis

Question 4

What do hair cells do in the vestibular system?

Answer 4

Hair cells support the stereocilia that transduce mechanical movement in the vestibular labyrinth into neural activity sent to the brain stem

Question 5

What are mechanoreceptors?

Answer 5

Mechanoreceptors are sensory receptors responsive to mechanical stimulation such as pressure, vibration, or movement.

Question 6

What is a receptor potential?

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Answer 6

It is a change in voltage of sensory receptor cells—hair cells for the vestibular system—in response to stimulation

Question 7

What are cristae?

Answer 7

Cristae are the specialized detectors of angular motion located in each semicircular canal in a swelling called the ampulla.

Question 8

What is an utricle?

Answer 8

An utricle is one of the two otolith organs. A saclike structure that contains the utricular macula. Also called utriculus.

Question 9

What is a saccule?

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Answer 9

A saccule is one of the two otolith organs. A saclike structure that contains the saccular macula. Also called sacculus

Question 10

What are maculae?

Answer 10

Maculae are specialized detectors of linear acceleration and gravity found in each otolith organ.

Question 11

What are otoconia?

Answer 11

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

Question 12

What do subjects report sensing when they are rotated in the dark (or with their eyes closed) for an extended period of time?

Answer 12

Subjects first feel a sense of motion consistent with their actual motion, but report feeling less and less motion over time until finally reporting no sensation of motion at all.

Question 13

How well do subjects do at reproducing passive translations of the body experienced in the dark?

Answer 13

Subjects do quite well at this task. When reproducing the translations with a joystick, subjects also reproduce the velocity of the passive-motion trajectory, indicating that the brain remembers and replicates the velocity trajectory.

Question 14

What is vection?

Answer 14

Vection is an illusory sense of self motion produced when one is not, in fact, moving.

Question 15

What happens when a subject looks at a rotating display for an extended period of time?

Answer 15

They report an illusory sensation of tilt in the direction opposite to the rotation of the stimulus.

Question 16

What is the vestibular-ocular reflex?

Answer 16

It is a compensatory eye movement that adjusts for changes in head position in order to keep the eye fixated on a target.

Question 17

What is the autonomic nervous system?

Answer 17

It is the part of the nervous system innervating glands, heart, digestive system, etc., and responsible for regulation of many involuntary actions.

Question 18

What is a situation in which the autonomic nervous system interacts with the vestibular system?

Answer 18

Motion sickness results from a discrepancy between visual and vestibular motion signals and results in the autonomic response of dizziness, nausea, and sometimes vomiting.

Question 19

What area of the cortex is exclusively devoted to processing vestibular information?

Answer 19

There isn’t one. There are areas of the cortex that respond to vestibular input, but they also tend to respond to visual input.

Question 20

What area of the brain is involved in spatial orientation perception?

Answer 20

The multisensory parieto-insular cortex. It receives input from both the semicircular canals and the otolith organs.

Question 21

What is Mal de Debarquement Syndrome?

Answer 21

After spending time on a boat or in the ocean, it is normal for people to feel a rocking sensation for a few hours. However, if the illusory sense of spatial disorientation, imbalance, and rocking lasts for a month or more, the person might be suffering from “disembarking sickness” or mal de debarquement syndrome.

Question 22

Describe Ménière’s Syndrome.

Answer 22

Patients suffering from this syndrome experience the sudden onset of dizziness, imbalance, and orientation as well as tinnitus, an illusory ringing sound. This combination of symptoms can cause patients to lose their balance or vomit, and unfortunately the symptoms can strike at any time.

Question 23

Vestibular Organs

Answer 23

The set of five organs–three semicircular canals and two otolith organs–located in each inner ear that sense head motion and head orientation with respect to gravity. These organs are also sometimes called the vestibular system or the vestibular labyrinth, but the name vestibular system is often used more generally to refer to the vestibular organs and their neural pathways.

Question 24

spatial orientation

Answer 24

A sense consisting of three interacting sensory modalities: the senses of linear motion, angular motion and tilt.

Question 25

dizziness

Answer 25

A commonly used lay term that nonspecifically indicates any form of perceived spatial disorientation, with or without instability.

Question 26

vertigo

Answer 26

A sensation of rotation or spinning. The term is sometimes used erroneously to mean any form of dizziness.

Question 27

Spatial disorientation

Answer 27

Any impairment o spatial orientation. More specifically, any impairment of our sense of linear motion, angular motion or tilt.

Question 28

Imbalance

Answer 28

Lack of balance; unsteadiness; nearly falling over

Question 29

Angular Motion

Answer 29

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

Question 30

Linear Motion

Answer 30

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

Question 31

Tilt

Answer 31

Attaining a sloping position like of the leaning tower of Pisa.

Question 32

Transduce

Answer 32

To convert from one form of energy to another.

Question 33

Semicircular canal

Answer 33

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

Question 34

Angular acceleration

Answer 34

The rate of change of angular velocity. Mathematically, the integral or angular acceleration of angular velocity and the integral of angular velocity is angular displacement. Angular acceleration, angular velocity, and angular displacement all mathematically represent angular motion.

Question 35

Otolith organ

Answer 35

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

Question 36

Liner acceleration

Answer 36

The rate of change of linear velocity. Mathematically, the integral of linear acceleration is linear velocity, and the integral of linear velocity is linear displacement, which is also referred to as “translation” Linear acceleration, linear velocity, and linear displacement all mathematically represent linear motion.

Question 37

Sense of angular motion

Answer 37

the spatial orientation modality that senses rotation

Question 38

Sense of linear motin

Answer 38

the spatial orientation modality that senses transalation

Question 39

sene of tilt

Answer 39

The spatial orientation modality that sense head inclination with respect to gravity

Question 40

amplitude (chapter 12)

Answer 40

The size (increase or decrease) of a head movement

Question 41

direcction

Answer 41

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

Question 42

velocity

Answer 42

The speed and direction in which something moves.

Question 43

acceleration

Answer 43

A change in velocity

Question 44

Hair cell (chapter 12)

Answer 44

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

Question 45

mechanoreceptor

Answer 45

A sensory receptor that responds to mechanical stimulation (pressure, vibration, or movement).

Question 46

Receptor potential

Answer 46

A change in voltage across the membrane of a sensory receptor cell (in the vestibular system, a hair cell) in response to stimulation