Chapter 3 - sensation and perception Flashcards
sensation
the process by which sensory organs in the eyes, ears, nose, mouth, skin and other tissues receive and detect stimuli
perception
the organization and interpretation of sensory stimuli by the brain
bottom up processing
taking basic information about incoming sensory stimuli and processing it for further interpretation
top down processing
drawing on past experiences and knowledge to understand and interpret sensory information
transduction
the process of transforming stimuli into neural signals
absolute thresholds
the weakest stimuli that can be detected 50% of the time
sensory adaptation
the process through which sensory receptors become less sensitive to constant stimuli
difference threshold
the minimum difference between two stimuli that can be noticed 50% of the time
weber’s law
the law stating that each of the five senses has its own constant ratio determining difference thresholds
signal detection theory
a theory explaining how internal and external factors influence our ability to detect weak signals in the environment
wavelength
the distance between wave peaks or troughs
hue
the color of an object determined by the wavelength of the light it reflects
amplitude
the height of a wave; distance from midpoint to peak or trough
saturation
color purity
cornea
the clear, outer layer of the eye that shields it from damage and focuses incoming light waves
iris
the muscle responsible for changing the size of the pupil
accommodation
the process by which the lens changes shape in order to focus on objects near and far
retina
the layer of the eye containing photoreceptor cells, which transduce light energy into neural activity
photoreceptors
specialized cells in the retina that absorb light energy and turn it into electrical and chemical signals for the brain to process
rods
photoreceptors that enable us to see in dim lighting; not sensitive to color, but useful for night vision
cones
photoreceptors that enable us to sense color and minute details
optic nerve
the bundle of axons from ganglion cells leading to the visual cortex
blind spot
a hole in the visual field caused by the optic disc (where optic nerve hits retina
dark adaptation
ability of the eyes to adjust to dark after exposure to bright light
light adaptation
ability of the eyes to adjust to light after being in the dark
feature detectors
neurons in the visual cortex specialized in detecting specific features of the visual experience such as angles lines and movements
trichromatic theory
the perception of color is the result of three types of cones, each sensitive to wavelengths in the red, green, and blue spectrums
afterimage
an image that appears to linger in the visual field after its stimulus or source is removed
opponent process theory
perception of color derives from a special group of neurons that respond to opponent colors
audition
the sense of hearing
pitch
the degree to which a sound is high or low determined by the frequency of its sound wave
frequency
the number of sound waves passing a given point per unit of time higher frequency is perceived as higher pitch and lower frequency is perceived as lower pitch
cochlea
fluid filled snail shaped organ of the inner ear lined with basilar membrane
place theory
states that pitch corresponds to the location of the vibrating hair cells along the cochlea
frequency theory
states that pitch is determined by thevibrating frequency of the sound wave basilar membrane and associated neural impulses
volley principle
states that the perception of the pitches between 400Hz and 4000Hz is made possible by neurons working together to fire in volleys
olfaction
the sense of smell
gustation
the sense of taste
gate control theory
suggests that the perception of pain will either increase or decrease through the interaction of biopsychosocial factors signals are sent to open or close gates that control the neurological pathways for pain
kinesthesia
sensory system that conveys information about body position and movement
proprioceptors
specialized nerve endings primarily located in the muscles and joints that provide information about body location and orientation
vestibular sense
the sense of balance and equilibrium
illusion
a perception that is inconsistent with sensory data
gestalt
the natural tendency for the brain to organize stimuli into a whole, rather than perceiving the parts and pieces
figure-ground
a central principle of gestalt psychology involving the shifting of focus; as attention is focused on one object all other features drop or recede into the background
depth perception
the ability to perceive three dimensional objects and distances
binocular cues
information gathered from both eyes to help judge depth and distance
convergences
a binocular cue used to judge distance and depth based on the tension of the muscles that direct where the eyes are focusing
retinal disparity
a binocular cue that uses the difference between the images the two eyes see to determine the distance of objects
monocular cues
depth and distance cues that require the use of only one eye
perceptual constancy
the tendency to perceive objects in our environment as stable in terms of shape size and color regardless of changes in the sensory data received
shape constancy
an object is perceived as maintaining its shape regardless of the image projected on the retina
size constancy
an object is perceived as maintaining its size regardless of the images projected on the retina
color constancy
objects are perceived as maintaining their color even with changing sensory data
perceptual set
the tendency to perceive stimuli in a specific manner based on past experiences and expectations
extrasensory perception
the purported ability to obtain information about the world without any sensory stimuli
parapsychology
the study of extrasensory perception
