OpenStax Psychology 2e Chapter 5

Sensation

what happens when sensory information is detected by a sensory receptor

Transduction

conversion from sensory stimulus energy to action potential

Absolute threshold

minimum amount of stimulus energy that must be present for the stimulus to be detected 50% of the time

Subliminal message

message presented below the threshold of conscious awareness

Just noticeable difference (jnd)/ difference threshold

difference in stimuli required to detect a difference between the stimuli

Perception

way that sensory information is interpreted and consciously experienced

Bottom-up processing

system in which perceptions are built from sensory input

Top-down processing

interpretation of sensations is influenced by available knowledge, experiences, and thoughts

Sensory adaptation

not perceiving stimuli that remain relatively constant over prolonged periods of time

Inattentional blindness

failure to notice something that is completely visible because of a lack of attention

Signal detection theory

change in stimulus detection as a function of current mental state

Amplitude

height of a wave

Wavelength

length of a wave from one peak to the next peak

Frequency

number of waves that pass a given point in a given time period

Hertz (Hz)

cycles per second; measure of frequency

Visible spectrum

portion of the electromagnetic spectrum that we can see

Electromagnetic spectrum

all the electromagnetic radiation that occurs in our environment

Pitch

perception of a sound's frequency

Decibels (dB)

logarithmic unit of sound intensity

Timbre

sound's purity

Cornea

transparent covering over the eye

Pupil

small opening in the eye through which light passes

Iris

colored portion of the eye

Lens

curved, transparent structure that provides additional focus for light entering the eye

Fovea

small indentation in the retina that contains cones

Retina

light-sensitive lining of the eye

Photoreceptor cells

light-detecting cell

Cones

specialized photoreceptor that works best in bright light conditions and detects color

Rods

specialized photoreceptor that works well in low light conditions

Optic nerve

carries visual information from the retina to the brain

Blind spot

point where we cannot respond to visual information in that portion of the visual field

Optic chiasm

X-shaped structure that sits just below the brain's ventral surface; represents the merging of the optic nerves from the two eyes and the separation of information from the two sides of the visual field to the opposite side of the brain

Trichromatic theory of color vision

color vision is mediated by the activity across the three groups of cones

Opponent-process theory of color perception

color is coded in opponent pairs: black-white, yellow-blue, and red-green

Afterimage

continuation of a visual sensation after removal of the stimulus

Depth perception

ability to perceive depth

Binocular cues

cue that relies on the use of both eyes

Binocular disparity

slightly different view of the world that each eye receives

Monocular cues

cue that requires only one eye

Linear perspective

perceive depth in an image when two parallel lines seem to converge

Pinna

visible part of the ear that protrudes from the head

Tympanic membrane

eardrum

Ossicles

the three tiny bones in the middle ear

Malleus

middle ear ossicle; also known as the hammer

Incus

middle ear ossicle; also known as the anvil

Stapes

middle ear ossicle; also known as the stirrup

Cochlea

fluid-filled, snail-shaped structure that contains the sensory receptor cells of the auditory system

Hair cells

auditory receptor cell of the inner ear

Basilar membrane

thin strip of tissue within the cochlea that contains the hair cells which serve as the sensory receptors for the auditory system

Temporal theory of pitch perception

sound's frequency is coded by the activity level of a sensory neuron

Place theory of pitch perception

different portions of the basilar membrane are sensitive to sounds of different frequencies

Monaural cue

one-eared cue to localize sound

Binaural cue

two-eared cue to localize sound

Interaural level difference

sound coming from one side of the body is more intense at the closest ear because of the attenuation of the sound wave as it passes through the head

Interaural timing difference

small difference in the time at which a given sound wave arrives at each ear

Deafness

partial or complete inability to hear

Congenital deafness

deafness from birth

Conductive hearing loss

failure in the vibration of the eardrum and/or movement of the ossicles

Sensorineural hearing loss

failure to transmit neural signals from the cochlea to the brain

Ménière's disease

results in a degeneration of inner ear structures that can lead to hearing loss, tinnitus, vertigo, and an increase in pressure within the inner ear

Vertigo

spinning sensation

Cochlear implants

electronic device that consists of a microphone, a speech processor, and an electrode array to directly stimulate the auditory nerve to transmit information to the brain

Four groups of taste

sweet, salty, sour bitter

Umami

taste for monosodium glutamate

Taste buds

grouping of taste receptor cells with hair-like extensions that protrude into the central pore of the taste bud

Olfactory receptor

sensory cell for the olfactory system

Olfactory bulb

bulb-like structure at the tip of the frontal lobe, where the olfactory nerves begin

Pheromones

chemical message sent by another individual

Meissner's corpuscles

touch receptor that responds to pressure and lower frequency vibrations

Pacinian corpuscles

touch receptor that detects transient pressure and higher frequency vibrations

Merkel's disks

touch receptor that responds to light touch

Ruffini corpuscles

touch receptor that detects stretch

Thermoception

temperature perception

Nociception

sensory signal indicating potential harm and maybe pain

Inflammatory pain

signal that some type of tissue damage has occurred

Neuropathic pain

pain from damage to neurons of either the peripheral or central nervous system

Congenital insensitivity to pain (congenital analgesia)

genetic disorder that results in the inability to experience pain

Vestibular sense

contributes to our ability to maintain balance and body posture

Proprioception

perception of body position

Kinesthesia

perception of the body's movement through space

Gestalt psychology

field of psychology based on the idea that the whole is different from the sum of its parts

Figure-ground relationship

segmenting our visual world into figure and ground

Proximity

things that are close to one another tend to be grouped together

Similarity

things that are alike tend to be grouped together

Good continuity

(also, continuity) we are more likely to perceive continuous, smooth flowing lines rather than jagged, broken lines

Principle of closure

organize perceptions into complete objects rather than as a series of parts

Pattern perception

ability to discriminate among different figures and shapes

Perceptual hypothesis

educated guess used to interpret sensory information