Sensation And Perception Ch.3

Front 1

Amacrine cell

Back 1

A neuron that transmits signals laterally in the retina. Amacrine cells synapse with bipolar cells and ganglion cells.

Front 2

Belongingness

Back 2

The hypothesis that an area’s appearance is influenced by the part of the surroundings that the area appears to belong to.

explain:
-Benary cross
-White’s illusion

Front 3

Benary cross

Back 3

-significant because the two areas that appear different both receive the same amount of lateral inhibition

Front 4

Bipolar cell

Back 4

A retinal neuron that receives inputs from the visual receptors and sends signals to the retinal ganglion cells.

Front 5

Center-surround antagonism

Back 5

The competition between the center and surround regions of a center-surround receptive field, caused by the fact that one is excitatory and the other is inhibitory. Stimulating center and surround areas simultaneously decreases responding of the neuron, compared to stimulating the excitatory area alone.

Front 6

Center-surround receptive field

Back 6

A receptive field that consists of a roughly circular excitatory area surrounded by an inhibitory area, or a circular inhibitory center surrounded by an excitatory surround.

Front 7

Complex cell

Back 7

A neuron in the visual cortex that responds best to moving bars with a particular orientation.

Front 8

Contrast

Back 8

The difference in light intensity between two areas. For a visual grating stimulus, the contrast is the amplitude of the grating divided by its mean intensity.

Front 9

Contrast sensitivity

Back 9

Sensitivity to the difference in the light intensities in two adjacent areas. Contrast sensitivity is usually measured by taking the reciprocal of the minimum intensity difference between two bars of a grating necessary to see the bars.

Front 10

Contrast threshold

Back 10

The intensity difference that can just barely be seen between two areas. This is often measured using gratings with alternating light and dark bars.

Front 11

Convergence (neural)

Back 11

When many neurons synapse onto a single neuron.

Front 12

End-stopped cell

Back 12

A cortical neuron that responds best to lines of a specific length that are moving in a particular direction.

Front 13

Excitatory area

Back 13

Area of a receptive field that is associated with excitation. Stimulation of this area causes an increase in the rate of nerve firing.

Front 14

Excitatory-center-inhibitory-surround receptive field

Back 14

A center-surround receptive field in which stimulation of the center area causes an excitatory response and stimulation of the surround causes an inhibitory response.

Front 15

Extrastriate cortex

Back 15

Areas in the cerebral cortex outside the striate cortex. This term is most commonly used to refer to areas associated with vision that are outside the primary visual receiving area in the striate cortex.

Front 16

Feature detector

Back 16

A neuron that responds selectively to a specific feature of the stimulus.

Front 17

Ganglion cell

Back 17

A neuron in the retina that receives inputs from bipolar and amacrine cells. The axons of the ganglion cells that travel out of the eye in the optic nerve.

Front 18

Grating

Back 18

A stimulus pattern consisting of alternating bars with different lightnesses or colors.

Front 19

Hering grid

Back 19

A geometrical display that results in the illusion of dark areas at the intersection of two white “corridors."

explaination:lateral inhibition.

Front 20

Horizontal cell

Back 20

A neuron that transmits signals laterally across the retina. Horizontal cells synapse with receptors and bipolar cells.

Front 21

Inhibitory area

Back 21

Area of a receptive field that is associated with inhibition. Stimulation of this area causes a decrease in the rate of nerve firing.

Front 22

Inhibitory-center-excitatory-surround receptive field

Back 22

A center-surround receptive field in which stimulation of the center causes an inhibitory response and stimulation of the surround causes an excitatory response.

Front 23

Lateral geniculate nucleus (LGN)

Back 23

The nucleus in the thalamus that receives inputs from the optic nerve and, in turn, sends fibers to the cortical receiving area for vision.

Front 24

Lateral inhibition

Back 24

Inhibition that is transmitted laterally across a nerve circuit. In the retina, lateral inhibition is transmitted by the horizontal and amacrine cells.

Front 25

Mach band

Back 25

Perception of a thin dark band on the dark side of a light–dark border and a thin light band on the light side of the border. These bands are an illusion because they occur even though corresponding intensity changes do not exist.

Front 26

Neural circuit

Back 26

A number of neurons that are connected by synapses.

Front 27

Neural plasticity

Back 27

The capacity of the nervous system to change in response to experience. Examples are how early visual experience can change the orientation selectivity of neurons in the visual cortex and how tactile experience can change the sizes of areas in the cortex that represent different parts of the body. See also Experience-dependent plasticity; Selective rearing.

Front 28

Ommatidium

Back 28

A structure in the eye of the Limulus that contains a small lens, located directly over a visual receptor. The Limulus eye is made up of hundreds of these ommatidia.

Good for Research:lateral inhibition

Front 29

Orientation

Back 29

The angle of a stimulus relative to vertical.

Front 30

Orientation tuning curve

Back 30

A function relating the firing rate of a neuron to the orientation of the stimulus.

Front 31

Receptive field

Back 31

A neuron’s receptive field is the area on the receptor surface (the retina, for vision; the skin, for touch) that, when stimulated, affects the firing of that neuron.

Front 32

Selective adaptation

Back 32

A procedure in which a person or animal is selectively exposed to one stimulus and then the effect of this exposure is assessed by testing with a wide range of stimuli. Exposing a person to vertical bars and then testing a person’s sensitivity to bars of all orientations is an example of selective adaptation to orientation.

Front 33

Selective rearing

Back 33

A procedure in which animals are reared in special environments.

-kittens in vertical TUBE

Front 34

Simple cortical cell

Back 34

A neuron in the visual cortex that responds best to bars of a particular orientation.

Front 35

Simultaneous contrast

Back 35

The effect that occurs when surrounding one color with another changes the appearance of the surrounded color.

Front 36

Size-tuning curves

Back 36

A function that indicates a neuron’s response to stimuli of different sizes. Gratings, in which the size of the bars width can be varied, are usually used as stimuli to determine size-tuning curves.

Front 37

Striate cortex

Back 37

The visual receiving area of the cortex, located in the occipital lobe.

Front 38

Superior colliculus

Back 38

-controls eye movements

receives 10% percent of the ganglion cell fibers that leave the eye in the optic nerve

Front 39

Tuning curve, orientation

Back 39

See Orientation tuning curve.

Front 40

Visual acuity

Back 40

The ability to resolve small details.

Front 41

White’s illusion

Back 41

A display in which two rectangles are perceived as differing in lightness even though they both reflect the same amount of light and even though the rectangle that is perceived as lighter receives more lateral inhibition than the one perceived as darker.