Chapter 4: Sensation and Perception Flashcards
synesthesia
the perceptual experience of one sense that is evoked by another sense
sensation
simple stimulation of a sense
perception
the organization, identification and interpretation of a sensation in order to form a mental representation
transduction
what takes place when many sensors in the body convert physical signals from the environment into encoded neural signals sent to the CNS
psychophysics
methods that measure the strength of a stimulus and te observer;s sensitivity to that stimulus
absolute threshold
the minimal intensity needed to just barely detect a stimulus
just noticeable difference (JND)
the minimal change in a stimulus that can just barely be detected
Weber’s Law
the just noticeable difference of a stimulus is a constant proportion despite variation in intensity
signal detection theory
an observation that the response to a stimulus depend both on a person’s sensitivity to the stimulus in the presence of noise and on a person’s response criterion
sensory adaptation
sensitivity to prolonged stimulation tends to decline over time as an program adapts to current conditions
visual acuity
ability to see fine detail
retina
light-sensitive tissue lining the back of the eyeball
accommodation
the process by which the eye maintains a clear image on the retina
cones
photoreceptors that detect color, operate under normal daylight conditions, and allow us to focus on fine detail
rods
photoreceptors that become active under low-light conditions for night vision
fovea
an area of the retina where vision is the clearest and there are no rods at all
blind spot
a location in the visual field that produces no sensation on the retina because the corresponding are of the retina contains neither rods nor cones and therefore has no mechanism to sense light
receptive field
the region of the sensory surface that when stimulated, causes a change in the firing rate of te neuron
trichromatic color representation
the pattern of responding across the three types of cones that provides a unique code for each color
color-opponent system
pairs of visual neurons that work in opposition