unit 3 chapter 4 Flashcards
(26 cards)
Sensation
The process of registering the stimulation of sensory receptors by an external physical stimulus.
Perception
The process of organizing sensory informa- tion to form a meaningful interpretation.
Bottom-up processing
The stimulus-driven process of sensation that registers external physical energy and translates it innto neural encoding
Stimulus
Physical energy in the world registered by a sen- sory organ, including light, sound, and smell.
Top-down processing
Perception through the use of information in mem- ory to organize incoming sensations.
Perceptual set
The influence of recent processing as a framework for continuing perception.
Transduction
The process in which physical energy in the world is translated into an electrochemical signal—neurons firing—that represents sensation in the brai
Sensory receptor
Specialized cells in each sense organ that react to only particular kinds of external physical stimulation.
Absolute threshold
The lowest amount of physical energy that can be detected reliably 50 percent of the time using a given sense organ.
Signal detection theory
A sensory testing method that takes into account both the actual stimulus intensity and your readiness to respond
Difference threshold
The smallest difference in sensation that is reliably detectable
Just noticeable difference (jnd)
The smallest amount of change between two stimuli that a person can detect at least half of the time.
Weber’s Law
As the stimulus becomes stronger or larger, so does the just noticeable dif- ference between it and other similar stimuli.
Subliminal perception
Sensation registered “below threshold,” without conscious awareness of its occurrence.
Sensory adaptation
A change in responsiveness to the same stimulation in a sensory organ over time
Wavelength
The distance between peaks of incoming light waves that determines their color.
Retina
The layer of sensory receptor cells lining the back wall of the eye.
Rod cells
Rod-shaped cells in the retina that register degrees of lightness and darkness.
cone cells
Cone-shaped cells on the retina that recognize colors.
Dark adaptation
The increased sensitivity experi- enced when your eyes adjust to lower levels of available light.
Fovea
The focal point of the retina where image process- ing is sharpest due to more cone cells.
Photoreceptors
The rod and cone cells in the retina that register the presence of light waves.
Bipolar cells
Cells that pro- cess incoming information from the rods and cones in the retina.
Ganglion cells
More complex cells that process patterns of receptor activation within the retina.
