In this technique, stimuli are presented in a graduated scale, and participants must judge the stimuli along a certain property that goes up or down
Method of Limits
the colored part of the eye; a muscle that controls the amount of light entering through the pupil
Iris
A bilateral structure (one is present in each hemisphere) in the thalamus that relays information from the optic nerve to the visual cortex
Lateral geniculate nucleus
Area of the cerebral cortex that receives input from the lateral geniculate nucleus, located in the occipital lobe and responsible for early visual processing
Primary Visual Cortex
The study of the relation between physical stimuli and perception events
Psychophysics
A method whereby the threshold is determined by presenting the observer with a set of stimuli, some above threshold and some below it, in a random order
Method of Constant Stimuli
the clear front surface of the eye that allows light in; it is also a major focusing element of the eye
Cornea
A term for opposite-side organization
Contralateral organization
The second area in the visual cortex that receives input; often considered the area that starts with visual associations rather than processing the input
V2
An illusion discovered by Gustav Fechner, and allows the viewer to see an "artificial spectrum of color"
Benham's top
In signal detection analysis, this response occurs when a nonsignal is accurately dismissed as not present
Correct Rejection
The area on the retina that is densest in cones but lacks rods.
Fovea
Retinal ganglion cells that project to the magnocellular layer of the lateral geniculate nucleus; they represent 10% of ganglion cells and possess high sensitivity to light
Parasol retinal ganglion cells
Starts with parasol retinal ganglion cells and continues through the visual cortex into the parietal lobe; often called the “where” pathway, as it codes for the locations of objects and their movement
Dorsal
After staring at a waterfall for some time, Aristotle noticed stationary objects moving upward. This waterfall illusion demonstrates
Motion Aftereffect
This SDT term is a subjective cut-off determined by the observer
Criterion
the number of photoreceptors that connect to each ganglion cell; more ___ occurs for rods than for cones
Convergence
Retinal ganglion cells that project to the parvocellular layer of the lateral geniculate nucleus; they represent 80% of ganglion cells, possess low sensitivity to light, and are sensitive to wavelength
Midget retinal ganglion cells
A column within V1 that is made up of neurons with similar responses to the orientation of a shape presented to those neurons
Orientation Column
The law describing the just-noticeable difference between two stimuli and its relationship with the strength of the stimuli
Weber's law
As the strength of a stimulus increases, the perceptual response increases even more
A condition causing an inability to focus on near objects, also called farsightedness
Hyperopia
Layers of the lateral geniculate nucleus with very small cells that receive input from K ganglion cells (bistratified retinal ganglion cells)
Koniocellular layers
Stacked up in columns, these groups of neurons are a part of V1 that are sensitive to color
Blobs
Helmholtz proposed that perception is not adequately determined by sensory information, so an educated guess is part of the process
Unconscious Inference