senses Flashcards
perception
how your brain interprets the sensory input
psychophysics
study of how physical stimuli are translated into psychological experience
stimulus
any detectable input from the environment
threshold
dividing point between energy levels that do and do not have a detectable effect
absolute threshold
minimum stimulus intensity that an organism can detect
just noticeable difference (JND)
smallest difference in stimulus intensity that a specific sense can detect
signal detection theory
detection of stimuli involves decision process as well as sensory process
subliminal perception
registration of sensory input without conscious awareness
sensory adaptation
gradual decline in sensitivity to prolonged stimulation
light
electromagnetic radiation. amplitude is the height, measures brightness. wavelength is between crests, measures hue (color). purity measures saturation (relative amount of whiteness in a picture).
what forms an upside down image of objects on the retina?
cornea and lens
lens
transparent eye structure that focuses the light rays falling on the retina
accommodation
when the curvature of the lens adjusts to alter visual focus. lens gets rounder with close objects, flatter with distant objects
nearsightedness
close objects clear, distant objects blurry
farsightedness
distant objects clear, close objects blurry
pupil
opening in the center of the iris that permits light to pass into the rear chamber of the eye
retina
neural tissue lining the inside back surface of the eye; it absorbs light, processes images, and sends visual information to the brain.
optic disk
hole in the retina where the optic nerve fibers exit the eye
arrange from closest to outside to farthest: rods and cones, ganglion cells, bipolar cells, horizontal cells, amacrine cells
ganglion cells, amacrine cells, bipolar cells, horizontal cells, rods and cones
cones
specialized vision receptors that play a key role in daylight vision and color vision and visual acuity.
fovea
tiny spot in the center of the retina that contains only cones; visual acuity is greatest at this spot
rods
specialized visual receptors that play a key role in night vision and peripheral vision
dark adaptation
the process in which the eyes become more sensitive to light in low illumination
light adaptation
the process whereby the eyes become less sensitive to light in high illumination
receptive field
retinal area that, when stimulated, affects the firing of the cell
optic chiasm
the point at which the optic nerves from inside half of each eye cross over and then project to the opposite half of the brain
simple cells (vision)
respond best to a line of the correct width, oriented at the correct angle, and located in the correct position in its receptive field
complex cells (vision)
care about width and orientation, but respond to any position on their receptive fields
feature detectors
neurons that respond selectively to very specific features of more complex stimuli
ventral stream
“what” pathway: perception of form and color
dorsal stream
“where” pathway: perception of motion and depth
visual agnosia
inability to recognize objects
prosopagnosia
inability to recognize familiar faces
subtractive color mixing
removing some wavelengths of light, leaving less light than was originally there. ends in black.
additive color mixing
superimposing lights, putting more lights in the mixture than exists in any one light by itself. ends in white.
color blindness
encompasses a variety of deficiencies in the ability to distinguish among colors
complementary colors
pairs of colors that produce gray tones when mixed together
afterimage
a visual image that persists after a stimulus is removed
opponent process theory
color perception depends on receptors that make opposite responses to three pairs of colors.
trichromatic theory
human eye has three types of receptors : blue, red, green
reversible figure
a drawing that is compatible with two interpretations that can shift back and forth
perceptual set
readiness to perceive a stimulus in a particular way
inattentional blindness
failure to see objects or events because one’s attention is focused elsewhere
feature analysis
process of detecting certain elements in visual input and assembling them into a more complex form
bottom up processing
progression from parts to whole
top down processing
progression from whole to parts
subjective contours
perception of contours when none actually exist
phi phenomenon
illusion of movement created by presenting visual stimuli in rapid succession
depth perception
interpretation of visual clues that indicate how near or far away objects are
binocular depth clues
clues about distance based on the differing views of the two eyes
retinal disparity
objects within 25 feet project images to slightly different locations on the right and left retinas, so the right and left eyes see slighly different views of the object
visible light
400-750 nanometers
how long does dark adaptation take?
30-45 minutes
interactions in retina
photoreceptor-bipolar cells-ganglion cells-optic nerve-brain
auditory accessory structures
pinna: outer ear flap thing auditory canal tympanic membrane: eardrum malleus: hammer incus: anvil stapes: stirrup
place theory
hair cell (organ of corti) at peak of wave. characteristic frequency
frequency theory
20 hertz-20firing per second. volley theory-a group of neurons fire simultaneously.
what does not go thru the thalamus
olfaction (smell). neurons-axons thru bony plate-> into brain. olfactory bulb connects to amygdala (emotion)
fast pain pathways & slow pain pathways
a-delta fibers & c fibers
proprioception
know where your body is.
connections: cerebellum (movement), autonomic nervous system (digestion), muscles of eyes (nausea).
vestibular sense
position of head in space
vestibular sacs
connect semicircular canals and cochlea. fluid filled. otoliths-ear stones-rest on hair endings.
kinesthesia
where body parts are in relation to each other
transduction
sound mechanical energy into neural response
in vision and hearing, sensory info route:
receptors->sensory nerves-> thalamus-> cerebral cortex
doctrine of specific nerve energies
stimulation of a particular sensory nerve provides codes for that one sense no matter how the stimulation takes place
sound route
ear, thalamus, primary auditory cortex, auditory association cortex
timbre
like being able to hear different instruments. purity or complexity of the sound
volume is
amplitude
pitch is
frequency
transduction of auditory info takes place in the
cochlea
neurons fire most rapidly in
bright light
lateral inhibition
contrast between light and dark, exaggerated.
visual action potentials that reach thalamus are created by
ganglion cells
sensation
what your senses pick up from physical stimuli
