Sensation+perception Flashcards
sensation
the process by which our sensory receptions and nervous system get and show stimulus energies from our environment.
perception
organizing and interpreting sensory information, allowing us to recognize meaningful objects and events
top-down vs bottom-up processing
top-down: stimulus –> perception/interp of stim, bottom up: preconcieved notions shape interpretation of stimulus
absolute threshold
the lowest amount of stimulus needed to detect a particular stimulus 50% of the time
signal detection theory
predicts how and when we detect the presence of a faint stimulus (signal) against background stimulation (noise)
subliminal
below your absolute threshold for conscious awareness
difference threshold
the minimum difference between 2 stimuli required for detection 505 of the time- we experience this as the just noticeable difference
Weber’s law
the principle that says to be perceived as different, to stimuli must differ by a constant minimum percentage
sensory adaptation
brain no longer attends to a constant stimulus, even if you think about it you can’t sense it (you hair on your head, unless you move)
sensory habituation
brain gets used to the stimulus and ignores it, but can still perceive it if given conscious thought (you stop paying attention to a fan, but you can still hear whether it is on or off if asked)
sensory accommodation
body changes to adjust to stimulus- pupils dilate to accomodats more light
transduction
conversion of one form of energy to another
energy senses
perceive energy- sight (light), hearing (sound waves), touch (pressure)
chemical senses
detect chemicals- smell and taste
feature detectors
individual neurons—or groups of neurons—in the brain which detect certain types of stimuli, like movements, shape, and angles,
parallel processing
multiple specialized cells provide a complete image by combining sensations of color, shape, shading and movement
trichromatic theory
AKA Young-Helmholtz theory. retina contains red, blue and green cones, combining cones creates other colors. based on color theory (all=white, none=black)
opponent-processing theory
visual information comes in pairs (red-green, yellow-blue, white-black), explains afterimages
cornea
protective lens covering the eye, helps focus light reflection onto retina
iris
colored muscle in eye that adjusts light intake
pupil
small adjustable opening in the eye that determines how much light is let in
lens
focuses incoming light rays in the eye
retina
multilayered tissue on inner surface of the eye
fovea
point of central focus in the eye
optic nerve
carries information from the eye to the brain