Sensation and Perception Flashcards
the amount something must be changed in order for a difference to be noticeable
just noticeable different
the minimum amount of stimulus energy (ex. how bright, loud, strong, etc) needed to activate the sensory system
absolute threshold
how different in magnitude 2 stimuli must be in order to be perceived to be different
difference threshold
law that states the change in stimulus intensity needed to produce JND divided by the stimulus intensity of the standard stimulus is a constant - measuring difference threshold
Weber’s Law
law that expresses the relationship between the intensity of the sensation and the intensity of the stimulus
Fechner’s Law
law that suggests Fechner’s law is incorrect, also related sensation and stimulus intensity
Steven’s Law
theory stating that non-sensory factors influence our perception, including experiences, motives, and expectations, and this differs between people
Signal Detection Theory
the tendency of subjects to respond in a certain way due to non-sensory factors
response bias
What is the first step of all sensory information processing?
reception
second step of sensory information processing - involves the translation of physical energy into neural impulses or action potentials
transduction
after transduction, electrochemical energy is sent to various __ in the brain along neural pathways to be processed across the nervous system
projection areas
clear, domelike window in front of your eye that gathers and focuses incoming light
cornea
a hole in the iris that contracts in bright light to keep light out, and expands in dim light to let more light in
pupil
colored part of the eye, has involuntary muscles and autonomic nerve fibers and controls the size of the pupil - therefore the amount of light entering the eye
iris
behind the iris, helps control the curvature of light coming in and can focus near or distant objects on the retina
lens
in the back of the eye, like a screen filled with neural elements and blood vessels, the image detecting part of the eye
retina
functions best in reduced illumination and allow perception only of achromatic colors, have low sensitivity to detail and are not involved in color vision
rods
used for color vision and perceiving fine detail, most effective in bright light, allow for chromatic and achromatic color vision
cones
theory that states the retina contains 2 kinds of photoreceptors, and the organization of the retina makes light pass through intermediate sensory neurons before reaching and stimulating the photoreceptors
duplexity/duplicity theory of vision
cells that group together to form the optic nerve
ganglion cells
where the fibers from the nasal half of retina cross paths
optic chaism
fibers from the __ halves of the retina don’t cross paths
temporal
scientists that found a neural basis for feature detection theory - suggests that certain cells in the cortex are maximally sensitive to certain features of stimuli
Hubel and Wiesel
cells in cortex that give information about the orientation and boundaries of an object
simple cells
cells in cortex that give advanced information about orientation, such as movement
complex cells
cells in cortex that give information about abstract features like object shape
hypercomplex cells
a physical, objective measurement that is simply the amount of light falling on an object
illumination
the subjective impression of the intensity of a light stimulus
brightness
the only photopigment in rods, helps with dark adaptation
rhodopsin
the phenomenon in which a target area appears brighter when surrounded by a darker stimulus than a lighter one
simultaneous brightness/contrast
explains simultaneous brightness/contrast, adjacent cells inhibit one another so if one cell is excited, others near it will be inhibited
lateral inhibition
color perception that has to do with lights, primary colors are blue, green, and red
additive
color perception that involves missing pigments, like finger paints
subjective
theory of color vision that states that the retina contains three types of color receptors (cones) which are sensitive to different colors (red, blue, green) - all colors are formed by combined stimulation of receptors
Young-Helmholtz/Trichromatic Theory
theory of color vision, states that there are four primary colors arranged in opposing pairs (yellow/blue and red/green), red would excite a red/green cell, green would inhibit it
Ewald Hering’s/Opponent Process Theory
a visual sensation that appears after a prolonged or intense exposure to a stimulus
afterimages
refers to the cue of depth perception, when object A covers/overlaps object B, we see object A as being in the front
interposition
convergence of parallel lines in the distance - only appear to converge, we know they do not actually, so we use this cue in forming our impression of depth
linear perspective
refers to the variations in perceive surface texture as a function of distance from an observer
texture gradients
in a car or train - choose a fixation point halfway between you and the horizon, and you will notice that objects closer to you appear to move in the same direction as you do
motion parallax
when the object rather than the perceiver is moving, the motion of the object gives us cues about the relative depth of parts of the object
kinetic depth effect
the distance between the eyes provides us with two disparate views due to the slight differences in horizontal positioning, combining the two views gives us perception of depth
binocular disparity/stereopsis
the integrated visual experience that stands out at the center of attention, one of the most important concepts in form perception
figure
the background against which a figure appears, one of the most important concepts in form perception
ground
Gestalt: elements close together tend to be perceived as one unit
law of proximity
Gestalt: objects that are similar to one another tend to be grouped together
law of similarity
Gestalt: elements that appear to follow the same direction (like a straight line or simple curve) tend to be grouped together, there is a tendency to perceive continuous patterns in stimuli rather than abrupt changes
law of good continuation
Gestalt: the tendency to perceive incomplete objects as being complete
law of closure
Gestalt: perceptual organization will always be “good” - symmetrical, regular, simple
law of Pragnanz
figure/ground configuration theory that there is a one-to-one correspondence between the object in the perceptual field and pattern of stimulation in the brain
Wolfgang Kohler’s Theory of Isomorphism
processing that is data driven, object perception that responds directly to the components of an incoming stimulus on the basis of fixed rules - then sums up the components to arrive at the whole pattern
bottom-up
processing that is conceptually driven, object perception guided by conceptual processes such as memories and expectations that allow the brain to recognize the whole object, then recognize the components
top-down
illusion that occurs when 2 dots flashed in different locations in succession are perceived as a moving dot
apparent motion
illusion of motion occurring when everything around a stationary light is moved
induced motion
illusion that occurs when a light viewed in a totally dark room seems to move, probably because of involuntary eye movements and no frame of reference
autokinetic effect
if a moving object is viewed for an extended period of time, it will appear to move in the opposite direction when the motion stops
motion after-effect
an actual stimulus or event in the world
distal stimulus
the information our sensory receptors receive about the object (in vision, this is the image on the retina)
proximal stimulus
we don’t perceive objects as changing sized, even when retinal size of the object changes
size constancy
Law that size constancy depends on apparent distance - the farther away an object appears to be, the most scaling device in the brain will compensate for its retinal size doubles
Emmert’s Law
We see a shape as consistent, ex. we see a door as a rectangle, though in the course of opening/closing it, it can be a rectangle, trapezoid, or a line
shape constancy
despite changes in the illumination of an object, the apparent lightness of the object remains unchanged because levels of illumination are the same for both object and background
lightness constancy
the perceived color of an object remains constant despite changes in the spectrum of light falling on it
color constancy
way of studying infant perception, record amount of time looking at 2 different stimuli, if there is a difference it can be inferred that the infant can discriminate between the two and prefers the one looked at the longest
preferential looking
way of studying infant perception, when a new stimulus is presented to an infant, he will orient towards it - can tell the difference between the old stimulus they are used to and a new one
habituation
number of sound wave cycles per second, measured in Hertz
frequency
amplitude of sound waves measured in decibels
intensity
the subjective experience of the magnitude or intensity of sound
loudness
subjective experience of the magnitude or intensity of sound
pitch
the quality of a particular sound, related to the complexity of a sound wave or measure of frequency
timbre
part of the ear visible from the outside, main function of channelling sounds into the auditory canal
pinna
channels sound into the eardrum, which vibrates according to incoming sound waves
auditory canal
3 tiny bones in the ear that transmit vibrations of the tympanum into the inner ear
ossicles
edge of stirrup rests on the ___, which is the entrance to the middle ear, which contains the ___
oval window, cochlea
resting on the basilar membrane, composed of hair cells which are the receptors for hearing (like rods and cones in the eye), bending of hair cells causes electrical charges
organ of corti
signals are transmitted out of the cochlea along the nerve fibers, which connects to the ___ and eventually reaches the ___ cortex
auditory nerve, temporal
pitch perception theory that different pitches cause different places of the basilar membrane to vibrate, which causes different hair cells to bend
Helmholtz’s Place-Resonance Theory
theory that suggests that basilar membrane vibrates as a whole, and rate of vibration = frequency of stimulus
frequency theory
principle in which high rates of neural firing can be maintained if nerve fibers work together
volley principle
the movement of the basilar membrane is maximal at different places along the basilar membrane for each different frequency, though the entire membrane vibrates at stimulus (high frequencies closer to cochlea near oval window, low frequencies vibrate near apex/tip of cochlea)
Bekesy’s Traveling Wave
smell receptors are called
olfactory epithelium
4 categories of touch
pressure, pain, warmth, cold
occurs in receptors and information travels to somatosensory cortex in parietal lobe of the brain
transduction
the minimum distance necessary between two points of stimulation on the skin such that the points will be felt as 2 distinct stimuli
2 point threshold
temperature is judged relative to physiological zero, or the temperature of the skin
physiological zero
there is a “gating” mechanism that can turn pain signals on and off, affecting whether we perceive pain, located in spinal cord and is able to block input from sensory fibers before brain receives pain signals
gate theory of pain
our sense of body position
proprioception
balance and body position relative to gravity
vestibular sense
receptors for balance, located in inner ear above and behind cochlea
semicircular canals
awareness of body movement and position, specifically with muscle, tendon, and joint position since receptors are located at/near them
kinesthetic sense
acts as a filter between sensory stimuli and our processing systems - if a stimulus is attended to, it passes through a filter for further analysis, if not it is lost
selective attention
when 2 ears are presented with 2 different messages simultaneously, it has shown that we can attend to one message an dampen out the other
dichotic listening
law that states maintaining attention requires maintaining arousal, performance is worst at extremely low or high levels, optimal at intermediate level
Yerkes-Dodson Law
