Sensation and Perception Flashcards
Covers lectures from February 1, 2013 through February 8, 2013
sensation
the sense organ’s detection of external stimuli, their responses to the stimuli and the transmission of these responses to the brain
perception
the processing, organization and interpretation of sensory signals its results in an internal representation of the stiumulus
transduction
the process by which sensory receptors produce neural impulses when they receive physical or chemical stimulation
sensory coding
the process by which sensory organics translate the physical properties of stimuli into patterns of neural impulses
difference threshold
the just difference between two stimuli
absolute threshold
the minimum intensity of stimulation that must occur before you experience the sensation
signal detection theory
a theory of perception based on the idea that the detection of a faint stimulus requires a judgement
sensory adaptation
a decrease in sensitivity to a constant level of stimulation
pupil
the small opening in the ye, it lets in light waves
iris
the colored muscular circle on the surfaces of the yes; it changes shape to let in more or less light
cornea
the clear outer covering of the eye
lens
the structure in the eye that bends light farther inwards and further focuses the light
retina
the thin inner surfaces of the back of the eyeball; it contains the photoreceptors that transduce light into neural signals
fovea
the center of the retina where cones are densely packed
optic disk
where the optic nerve stems from on the eyeball
rods
retinal cells that respond to low levels of illumination and result in black and white perception
cones
retinal cells that respond to higher levels of illumination and result in color perception
optic nerve
a bundle of axons that extends from ganglion cells at the back of the eyeball
photopigments
light sensitive chemicals that initiate the transduction of light waves in electrical neural impulses
accomodation
the flattening of the lens to focus on distant objects and thickening of the lens to focus on closer objects
ganglion cells
first to generate action potential in the eyeball
trichromatic color theory
color vision results from activity in three different types of cones that are sensitive to different wavelenghts
subtractive color mixing
a process of color mixing that occurs within the stimulus itself; a physical not a psychological process
additive color mixing
a process of color mixing that occurs when different wavelengths of light interact within the eye’s receptors; a psychological process
audition
hearing; the sense of sound perception
sound wave
pattern of changes in air pressure during a period of time; it produces the percept of a sound
eardrum
the thin membrane that marks the beginning of the middle ear; sound waves cause it to vibrate
outer ear
the visible portion of the ear and auditory canal
ossicles
three tiny bones commonly called the hammer, anvil and stirrup
round window
the membrane at the end of the cochlea
oval window
a membrane within the cochlea
basilar membrane
the membrane in the cochlea against which cochlear fluid washes
auditory nerve
the bundle of axons that carry electrical stimulus from the ear to the brain
cochlea
a fluid filled tube that curls into a snail like shape with a membrane at the end called the round window
blindsight
a condition in which people who are blind have some spared visual capacities in the absence of any visual awareness
ventral stream
the lower visual pathway specialized for the perception and recognition of objects
dorsal stream
the higher visual pathway specialized for determining an object’s place in space and relating it to other objects in a scene
reversible figure illusion
a classic illustration when, in an ambiguous figure, the figure and ground periodically reverse
bottom-up processing
a hierachical model of pattern recognition in which data are relayed from one level of mental processing to the next, always moving to a higher level of processing.
top-down processing
a hierarchical model of pattern recognition in which information at higher levels of mental [processing can also influence lower, “earlier” levels in the processing hierarchy
illusory contours
the perception of contours and cues to depth even thought the depth does not actually exist
good continuation
the tendency to interpret intersecting lines as continuous rather that as changing direction radically
principle of proximity
the closer two figures are to each other, the more likely we are to group them and see them as part of the same object
principle of similarity
the tendency to group figures according to how closely they resemble each other, whether in shape, color or orientation
occluder
anything that hides from view a portion of an object or an entire object
prosopagnosia
a deficit in a person’s ability to recognize faces, but not other objects
fusiform gyrus
a portion of the right hemisphere specialized for the the perception of faces
binocular depth cues
cue of the depth perception that arise from the face that people have two eyes
monocular depth cues
cues of depth perception that are available to each eye alone
binocular disparity
a depth cue that arises because of the distance between a person’s eyes results in a slight difference in retinal imagery
convergence
a cue of binocular depth perception; when a person views a nearby object, the eye muscle turn the eyes inward
occlusion
a monocular cue; a near object occludes (blocks) an object that is farther away
relative size
a monocular cue; far-off objects project a small retinal image than close objects, if the far-off object and close objects are the same physical size
linear perspective
seemingly parallel lines appear to converge in the distance
familiar size
we know how large familiar objects are, so we can tell how far away they are by the size of their retinal images
texture gradient
as a uniformly textured surface recedes, its texture continuously becomes denser
position relative to horizon
all else being equal, objects below the horizon that appear higher in the visual field are perceived as being father away
motion aftereffects
when you gaze at a moving image for a long time and then look at a stationary scene, you experience momentary impression that the new scene is moving in the opposite direction from the moving image
compensation for head and eye motion
the brain calculates an object’s perceived movements by monitoring the movement of the yes, perhaps also the head as they track a moving object
stroboscopic motion perception
a perceptual illusion that occurs when two or more slightly different images are presented in rapid succession
perceptual constancy
correctly perceiving objects as constant in their shape, size, color and lightness despite raw sensory data that could mislead perception
kinesthetic sense
perception of the position in space and movement of our bodies and our limbs
vestibular sense
perception of balance
three primaries law of color
almost any color can be created by combining just three wavelengths
gate control theory of pain
in order to experience pain, pain receptors must be activated at a neural gate in t he spinal cord must allow the signals through to the brain
