Week 8 Flashcards
Opponent Process
The representation of colours by the rate of firing of two types of neurones: red/green and yellow/blue
Opponent Process Theory
The theory that the perception of colour is the result of the activity of three opponent-process channels. (Red/Green, Blue/Yellow, Black/White)
Photoreceptor
A receptive cell for vision in the retina; a rod or a cone
Cone
A photoreceptor that is responsible for acute daytime vision and for colour perception
Rod
A photoreceptor that is very sensitive to light but cannot detect changes in hue
Perception
The detection of the more complex properties of a stimulus, including its location and nature
Transduction
The conversion of physical stimuli into changes in the activity of receptor cells of sensory organs
Receptor Cell
A neuron that directly responds to a physical stimulus, such as light, vibrations, or aromatic molecules
Anatomical Coding
A means by which the nervous 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 in neurons
Psychophysics
A branch of psychology that measures the quantitative relation between physical stimuli and perceptual experience
Just-Noticeable Difference (JND)
The smallest difference between two similar stimuli that can be distinguished; also known as difference threshold
Weber Fraction
The ratio between a JND and the magnitude of a stimulus; reasonably constant over the middle range of most stimulus intensities
Threshold
The point at which a stimulus, or a change in the value of a stimulus, can just be detected
Difference Threshold
The smallest difference between two similar stimuli that can be distinguished; also known as JND
Signal Detection Theory
A mathematical theory of the detection of stimuli, which involves discriminating a signal from the noise in which is it embedded and which takes into account participants’ willingness to report detecting the signal
Receiver Operating Characteristic Curve (ROC 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
The transparent tissue covering the front of the eye
Sclera
The tough outer layer of the eye; the “white” of the eye
Iris
The pigmented muscle of the eye that controls the size of the pupil
Lens
The transparent organ situated behind the iris of the eye; helps focus an image on the retina
Accommodation
Changes in thickness of the lens of the eye that focus images of near or distant objects on the retina
Retina
The tissue at the back inside surface of the eye that contains the photoreceptors and associated neurons
| Thalamus
Information from the sensory organs and motor signals from subcortical structures like the basal ganglia are received by thalamic regions and relayed separately to the cortex. The thalamus is also involved in regulating wakefulness and sleep