sensation
the process by which our sensory receptors and nervous system receive and represent stimulus energies from our environment.
app: the picking up of info
perception
the process of organizing and interpreting sensory information, enabling us to recognize meaningful objects and events.
app: interpreting info, may be different between people
bottom-up processing
analysis that begins with the sensory receptors and works up to the brain’s integration of sensory information.
app: info, then interpret
top-down processing
information processing guided by higher-level mental processes, as when we construct perceptions drawing on our experience and expectations.
app: memory trigger, then interpret
selective attention
the focusing of conscious awareness on a particular stimulus.
app: purposeful focus
inattentional blindness
failing to see visible objects when our attention is directed elsewhere.
app: seeing but not noticing
change blindness
failing to notice changes in the environment.
app: super mega focus = blindness to enviroment
transduction
conversion of one form of energy into another. In sensation, the transforming of stimulus energies, such as sights, sounds, and smells, into neural impulses our brain can interpret.
app: electromagnetic energy into neurochemical energy within vision
psychophysics
the study of relationships between the physical characteristics of stimuli, such as their intensity, and our psychological experience of them.
app: study reception vs perception
absolute threshold
the minimum stimulation needed to detect a particular stimulus 50 percent of the time.
app: stimulation needed for detection
signal detection theory
a theory predicting how and when we detect the presence of a faint stimulus (signal) amid background stimulation (noise). Assumes that there is no single absolute threshold and that detection depends partly on a person’s experience, expectations, motivation, and alertness.
app: varying absolute threshold depending on the person
subliminal
below one’s absolute threshold for conscious awareness.
app: unable to be “noticed”
priming
the activation, often unconsciously, of certain associations, thus predisposing one’s perception, memory, or response.
app: association affecting perception
difference threshold
the minimum difference between two stimuli required for detection 50 percent of the time. We experience the difference threshold as a just noticeable difference (or jnd).
app: stimulation needed for recognition
Weber’s Law
the principle that, to be perceived as different, two stimuli must differ by a constant minimum percentage (rather than a constant amount).
app: percentage of differentiation
sensory adaptation
diminished sensitivity as a consequence of constant stimulation.
app: “its fine i’m used to it”
perceptual set
a mental predisposition to perceive one thing and not another.
app: systemic racism
extrasensory perception (ESP)
the controversial claim that perception can occur apart from sensory input; includes telepathy, clairvoyance, and precognition.
app: perception without reception
parapsychology
the study of paranormal phenomena, including ESP and psychokinesis.
app: study of perception without reception
wavelength
the distance from the peak of one light or sound wave to the peak of the next. Electromagnetic wavelengths vary from the short blips of cosmic rays to the long pulses of radio transmission.
app:distance between peaks
hue
the dimension of color that is determined by the wavelength of light; what we know as the color names blue, green, and so forth.
app: color
intensity
the amount of energy in a light or sound wave, which we perceive as brightness or loudness, as determined by the wave’s amplitude.
app: brightness/amount of energy
pupil
the adjustable opening in the center of the eye through which light enters.
app: black part of the eye that is adjusted by the iris
iris
a ring of muscle tissue that forms the colored portion of the eye around the pupil and controls the size of the pupil opening.
app: adjusts the pupil size
lens
the transparent structure behind the pupil that changes shape to help focus images on the retina.
app: focuses light on retina
retina
the light-sensitive inner surface of the eye, containing the receptor rods and cones plus layers of neurons that begin the processing of visual information.
app: has fovea, where most of the rods and cones are and where most of the light is focused by the lens
accommodation
the process by which the eye’s lens changes shape to focus near or far objects on the retina.
app: how the lense focuses things of different distance on the retina
rods
retinal receptors that detect black, white, and gray; necessary for peripheral and twilight vision, when cones don’t respond.
app: receptors for light and dark
cones
retinal receptor cells that are concentrated near the center of the retina and that function in daylight or in well-lit conditions. The cones detect fine detail and give rise to color sensations.
app: receptors for color
optic nerve
the nerve that carries neural impulses from the eye to the brain.
app: connects mechanical to neurological within vision
blind spot
the point at which the optic nerve leaves the eye, creating a “blind” spot because no receptor cells are located there.
app: place with no visual receptor cells
fovea
the central focal point in the retina, around which the eye’s cones cluster.
app: where the majority of rods and cones are, and where the majority of the light is focused
feature detectors
nerve cells in the brain that respond to specific features of the stimulus, such as shape, angle, or movement.
app: allows us to recognize familiarly and perceptual constancy
parallel processing
the processing of many aspects of a problem simultaneously; the brain’s natural mode of information processing for many functions, including vision. Contrasts with the step-by-step (serial) processing of most computers and of conscious problem solving.
app: simultaneous perception, an aspect of perceptual constancy and familiarity
Young-Helmholtz trichromatic (three-color) theory
the theory that the retina contains three different 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.
app: every visual color stems from red, green, and blue
opponent-process theory
the theory that opposing retinal processes (red-green, yellow-blue, 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.
app: colors cancel out the opposite colors,explains the whole inverted image illusion
gestalt
an organized whole. Gestalt psychologists emphasized our tendency to integrate pieces of information into meaningful wholes.
app: the tend to make sense of things automatically
figure-ground
the organization of the visual field into objects (the figures) that stand out from their surroundings (the ground).
app: perception of subject vs background
grouping
the perceptual tendency to organize stimuli into coherent groups.
app: making patterns
depth perception
the ability to see objects in three dimensions although the images that strike the retina are two-dimensional; allows us to judge distance.
app: sucks when you go to make a left turn
visual cliff
a laboratory device for testing depth perception in infants and young animals.
app: device for depth perception
binocular cues
depth cues, such as retinal disparity, that depend on the use of two eyes.
app: depth cues that need two eyes
retinal disparity
a binocular cue for perceiving depth: By comparing images from the retinas in the two eyes, the brain computes distance— the greater the disparity (difference) between the two images, the closer the object.
app: brain uses info from two eyes to determine depth
monocular cues
depth cues, such as interposition and linear perspective, available to either eye alone.
app: depth cues that only need one eye
phi phenomenon
an illusion of movement created when two or more adjacent lights blink on and off in quick succession.
app: lights in a circle that blink in order to look like its going around the circle
perceptual constancy
perceiving objects as unchanging (having consistent shapes, size, brightness, and color) even as illumination and retinal images change.
app: recognizing familiarity in different lighting, angles, etc
color constancy
perceiving familiar objects as having consistent color, even if changing illumination alters the wavelengths reflected by the object.
app: knowing the color even in different lighting
perceptual adaptation
in vision, the ability to adjust to an artificially displaced or even inverted visual field.
app: why we doing like “real mirrors”
audition
the sense or act of hearing.
app: hearing literally anything
frequency
the number of complete wavelengths that pass a point in a given time (for example, per second).
app: inversely proportional to wavelength
pitch
a tone’s experienced highness or lowness; depends on frequency.
app: high notes vs low notes, different pitches
middle ear
the chamber between the eardrum and cochlea containing three tiny bones (hammer, anvil, and stirrup) that concentrate the vibrations of the eardrum on the cochlea’s oval window.
app: connects vibration on eardrum to cochliea
cochlea
a coiled, bony, fluid-filled tube in the inner ear; sound waves traveling through the cochlear fluid trigger nerve impulses.
app: sound travels to trigger nerves
inner ear
the innermost part of the ear, containing the cochlea, semicircular canals, and vestibular sacs.
app: cochlea + balcning stuff
sensorineural hearing loss
hearing loss caused by damage to the cochlea’s receptor cells or to the auditory nerves; also called nerve deafness.
app: neurological deafness
conduction hearing loss
hearing loss caused by damage to the mechanical system that conducts sound waves to the cochlea.
app: mechanical deafness
cochlear implant
a device for converting sounds into electrical signals and stimulating the auditory nerve through electrodes threaded into the cochlea.
app: stimulates auditory nerve when cochlea cant
place theory
in hearing, the theory that links the pitch we hear with the place where the cochlea’s membrane is stimulated.
app: certain hairs are stimulated by certain frequencies
frequency theory
in hearing, the theory that the rate of nerve impulses traveling up the auditory nerve matches the frequency of a tone, thus enabling us to sense its pitch.
app: hairs move to match frequencies
gate-control theory
the theory that the spinal cord contains a neurological “gate” that blocks pain signals or allows them to pass on to the brain. The “gate” is opened by the activity of pain signals traveling up small nerve fibers and is closed by activity in larger fibers or by information coming from the brain.
app: small fibers constantly send pain, large fibers are blocked until stimulated
kinesthesia
the system for sensing the position and movement of individual body parts.
app: physical self-awareness of specific body parts
vestibular sense
the sense of body movement and position, including the sense of balance.
app: physical self-awareness of the body as a whole
sensory interaction
the principle that one sense may influence another, as when the smell of food influences its taste.
app: me with green beans in PreK
embodied cognition
in psychological science, the influence of bodily sensations, gestures, and other states on cognitive preferences and judgments.
app: physicality affecting perception
Gustav Fechner
German scientist and philosopher associated with absolute thresholds.
app: experiments with light photons and sound waves
Ernst Weber
Founder of Weber’s Law, associated with difference thresholds
app: experiments with light photons and sound waves
David Hubel
Neuroscientist who won a Nobel Prize for work regarding feature receptors
app: visual cortex research (motor detection)
Torsten Wiesel
Neuroscientist who won a Nobel Prize for work regarding feature receptors
app: visual cortex research (motor detection)