Unit 1 Part 1 B Terms

Question 1

Hallucinations

Answer 1

False sensory experiences, such as seeing something in the absence of an external visual stimulus

Question 2

Hypnagogic sensations

Answer 2

Bizarre experiences, such as jerking or a feeling of falling or floating weightlessly, while transitioning to sleep

Question 3

Delta waves

Answer 3

The large, slow brain waves associated with deep sleep

Question 4

Suprachiasmatic nucleus (SCN)

Answer 4

A pair of cell clusters in the hypothalamus that controls circadian rhythm

Question 5

Insomnia

Answer 5

Recurring problems in falling or staying asleep

Question 6

Narcolepsy

Answer 6

A sleep disorder characterized by uncontrollable sleep attacks. The affected person may lapse directly into REM sleep, often at inopportune times

Question 7

Sleep apnea

Answer 7

A sleep disorder characterized by temporary cessations of breathing during sleep and repeated momentary awakenings

Question 8

REM behavior disorder

Answer 8

A sleep disorder involving motor activity during REM sleep, which typically includes a physical enactment of dream sequences

Question 9

Dream analysis

Answer 9

a technique, originally used in psychoanalysis but now also used in some other psychotherapies, in which the content of dreams is interpreted to reveal underlying motivations or symbolic meanings and representations

Question 10

Sigmund Freud

Answer 10

Austrian neurologist; invented and developed psychoanalysis

Question 11

REM rebound

Answer 11

The tendency for REM sleep to increase following REM sleep deprivation

Question 12

Sensation

Answer 12

The process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment

Question 13

Sensory receptors

Answer 13

Sensory nerve endings that respond to stimuli

Question 14

Perception

Answer 14

The process by which our brain organizes and interprets sensory information, enabling us to recognize objects and events as meaningful

Question 15

Bottom up processing

Answer 15

Information processing that begins with the sensory receptors and works up to the brain’s integration of sensory information

Question 16

Top down processing

Answer 16

Information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations

Question 17

Transduction

Answer 17

Conversion of one form of energy into another. In sensation, the transforming of physical energy, such as sights, sounds, and smells, into neural impulses the brain can interpret

Question 18

Glutamate

Answer 18

Serves as the predominant excitatory neurotransmitter in the brain. Glutamate plays a critical role in cognitive, motor, and sensory functions

Question 19

Absolute threshold

Answer 19

The minimum stimulus energy needed to detect a particular stimulus 50 percent of the time

Question 20

Signal detection theory

Answer 20

A theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes there is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivation, and alertness

Question 21

Hue

Answer 21

The dimension of color that is determined by the wavelength of light

Question 22

Intensity

Answer 22

The amount of energy in a light wave or sound wave, which influences what we perceive as brightness or loudness; determined by the wave’s amplitude

Question 23

Cornea

Answer 23

The eye’s clear, protective outer layer, covering the pupil and iris

Question 24

Pupil

Answer 24

The adjustable opening in the center of the eye through which light enters

Question 25

Iris

Answer 25

A ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening

Question 26

Lens

Answer 26

The transparent structure behind the pupil that changes shape to help focus images on the retina

Question 27

Retina

Answer 27

The light-sensitive back inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information

Question 28

Acommodation

Answer 28

In sensation and perception, the process by which the eye’s lens changes shape to focus images of near or far objects on the retina

Question 29

Rods

Answer 29

Retinal receptors that detect black, white, and gray, and are sensitive to movement; necessary for peripheral and twilight vision, when cones don’t respond

Question 30

Cones

Answer 30

Retinal receptors that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. Cones detect fine detail and give rise to color sensations

Question 31

Optic nerve

Answer 31

The nerve that carries neural impulses from the eye to the brain

Question 32

Blind spot

Answer 32

The point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there

Question 33

Fovea

Answer 33

The central focal point in the retina, around which the eye’s cones cluster

Question 34

Trichromatic theory

Answer 34

The theory that the retina contains three different types of color receptors — one most sensitive to red, one to green, one to blue — which, when stimulated in combination, can produce the perception of any color

Question 35

Opponent process theory

Answer 35

The theory that opposing retinal processes (red-green, blue-yellow, white-black) enable color vision. For example, some cells are stimulated by green and inhibited by red; others are stimulated by red and inhibited by green

Question 36

Feature detectors

Answer 36

Nerve cells in the brain’s visual cortex that respond to specific features of the stimulus, such as shape, angle, or movement

Question 37

Audition

Answer 37

The sense or act of hearing

Question 38

Frequency

Answer 38

The number of complete wavelengths that pass a point in a given time