Sensation The detection of the elementary properties of a stimulus.
Perception detection of the more complex properties of a stimulus, including its location and
nature, involving learning
Transduction The conversion of physical stimuli into changes in the activity of receptor cells of
Receptor cell Neuron that directly responses to a physical stimuli
Anatomical Coding A means by which the nerves system represents information; different features are
coded by the activity of different neurons
Temporal Coding A means by which the nervous system represents information; different features
are coded by the pattern of activity of neurons (firing faster/slower)
Just-noticeable difference (jnd) – the smallest difference between two similar stimuli that can be
disguised; also called threshold.
Weber fraction Ratio between a just-noticeable difference and the magnitude of a stimulus;
reasonably constant over the middle range of most stimulus intensities.
ThresholdThe point at which a stimulus, or a change in the value of a stimulus, can be
Absolute thresholdmin. Value a stimulus can be detected
Signal detection theorya mathematical theory of the detection of stimuli, which involves discriminating a
signal from the noise in which it is embedded and which takes into account
participants’ willingness to report detecting the signal.
ROC curvereceiver operating characteristic curve – a graph of hits and false alarms of
participants under different motivational conditions, indicates people’s ability to
detect a particular stimulus
Wavelength The distance between adjacent waves of radiant energy; in vision, most closely
associated with the perceptual dimension of hue
Cornea transparent tissue covering the front of the eye
Sclera tough outer layer of the eye; the eye white
Iristhe pigmented muscle of the eye that controls the size of the pupil