sense percept

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

just noticeable difference: difference in stimuli required to detect a difference between the stimuli

mere-exposure effects: the result of developing a more positive attitude towards a stimulus after repeated instances of mere exposure to it.

priming: the process by which recent experiences increase a trait’s accessibility.

sensation: what happens when sensory information is detected by a sensory receptor

signal detection theory: change in stimulus detection as a function of current mental state

subliminal message: message presented below the threshold of conscious awareness

transduction: conversion from sensory stimulus energy to action potential

Weber’s law: Ernst Weber’s discovery that the difference threshold is a constant fraction of the original stimulus and bigger stimuli require larger differences to be noticed

bottom-up processing: system in which perceptions are built from sensory input

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

perception: way that sensory information is interpreted and consciously experienced

sensory adaptation: the reduction in sensitivity after prolonged exposure to a stimulus

top-down processing: interpretation of sensations is influenced by available knowledge, experiences, and thoughts

amplitude: height of a wave

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

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

cornea: transparent covering over the eye

electromagnetic spectrum: all the electromagnetic radiation that occurs in our environment

fovea: small indentation in the retina that contains cones

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

hertz (Hz): cycles per second; measure of frequency

iris: colored portion of the eye

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

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

optic nerve: carries visual information from the retina to the brain

peak: (also, crest) highest point of a wave

photoreceptor: light-detecting cell

pupil: small opening in the eye through which light passes

retina: light-sensitive lining of the eye

rod: specialized photoreceptor that works well in low light conditions

trough: lowest point of a wave

visible spectrum: portion of the electromagnetic spectrum that we can see

wavelength: length of a wave from one peak to the next peak

afterimage: continuation of a visual sensation after removal of the stimulus

binocular cue: cue that relies on the use of both eyes

binocular disparity: slightly different view of the world that each eye receives

depth perception: ability to perceive depth

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

monocular cue: cue that requires only one eye

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

synesthesia: the blending of two or more sensory experiences, or the automatic activation of a secondary (indirect) sensory experience due to certain aspects of the primary (direct) sensory stimulation.

trichromatic theory of color perception: color vision is mediated by the activity across the three groups of cones

vestibulo-ocular reflex: coordination of motion information with visual information that allows you to maintain your gaze on an object while you move.

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

cochlea: a fluid-filled, snail-shaped structure that contains the sensory receptor cells (hair cells) of the auditory system

hair cell: auditory receptor cell of the inner ear

incus: middle ear ossicle; also known as the anvil

malleus: middle ear ossicle; also known as the hammer

pinna: visible part of the ear that protrudes from the head

stapes: middle ear ossicle; also known as the stirrup

tympanic membrane: eardrum

binaural cue: two-eared cue to localize sound

cochlear implant: 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

conductive hearing loss: failure in the vibration of the eardrum and/or movement of the ossicles

congenital deafness: deafness from birth

deafness: partial or complete inability to hear

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

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

monaural cue: one-eared cue to localize sound

place theory of pitch perception: different portions of the basilar membrane are sensitive to sounds of different frequencies

sensorineural hearing loss: failure to transmit neural signals from the cochlea to the brain

temporal theory of pitch perception: sound’s frequency is coded by the activity level of a sensory neuron

vertigo: spinning sensation

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

olfactory receptor: sensory cell for the olfactory system

pheromone: chemical message sent by another individual

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

umami: taste for monosodium glutamate