Psych 1010: Unit 4

Sensation

Detection of physical energy by the sense organs.

Perception

How the brain interprets raw sensory data.

Photoreception

Sensory information related to light; processed by the eyes.

Mechanoreception

Sensory information related to pressure, vibration, and movement; processed by physical touch.

Chemoreception

Sensory information related to chemicals; associated with taste.

Transduction

Conversion of one energy form into another, such as light energy into action potentials for the brain.

Bottom-up processing

Perception based on simple sensory input.

Top-down processing

Perceptual processes derived from cognitive and memory processes for interpreting information.

Sensory adaptation

The process by which sensory functions become less sensitive to constant stimuli.

Psychophysics

The measurement of sensation.

Absolute threshold

Minimum intensity of a stimulus that a person can detect half the time.

Subliminal perception

Stimuli presented below the absolute threshold.

Just Noticeable Difference (JND)

The degree of difference that must exist between two stimuli before the difference is detected

Weber’s law

The principle that JND is relative to the intensity of the first stimulus.

JND in Marketing

Changes must be at or above the JND to be discernible.

Selective attention

Focusing on a specific aspect of sensory input while ignoring other stimuli.

Cocktail party effect

The phenomenon where we can recognize our names in a noisy environment

Change blindness

Failure to detect changes in the environment due to distractions.

Rods

Photoreceptors in the retina that detect black, white, and grey; sensitive to movement.

Cones

Photoreceptors responsible for sharp focus, color perception, and detail.

Feature detectors

Cells in the visual cortex sensitive to specific features of the environment.

Trichromatic theory

Theory that color perception is based on three types of cones (red, green, blue).

Opponent process theory

Theory that we perceive colors in terms of three pairs of opponent colors. red or green, blue or yellow, and black or white

Visual agnosia

Object recognition deficit due to damage in higher visual cortical areas.

Blindsight

Above-chance visual performance in cortically blind individuals.

Gestalt principles

Principles that determine how we organize sensory information into meaningful wholes.

Perceptual constancy

Recognition that objects remain constant despite changes in sensory input.

Depth perception

The brain's use of cues to determine depth from flat retinal images.

Texture gradient

Near objects appear to have more texture than distant objects.

Binocular depth cues

Depth cues that require both eyes, such as convergence and disparity.

Cochlea

Coiled tube in the ear filled with fluid that vibrates in response to sound.

Hair cells

Tiny cells in the cochlea that transmit neural messages when bent by vibrations.

Conductive deafness

Hearing loss due to malfunction of the ear or eardrum.

Nerve damage

Hearing loss due to damage in the auditory nerve.

McGurk effect

A phenomenon where visual and auditory senses interact to create a third perceived sound.

outear (pinna): Reverse megaphone – funnels sound in toward eardrum

eardrum

Part of the ear that vibrates when sound waves make contact

middle ear

Tiny chamber containing 3 tiny bones (stirrup, anvil, hammer) that act as mechanical amplifier

Cochlea

Coiled tube in ear filled with fluid that vibrates in response to sound

Basilar membrane

Runs through center of cochlea – divided into two chambers, covered with hair cells