Chapter 6

Front 1

Sensory receptors

Back 1

Specialized neurons that detect a particular category of physical events

Front 2

Sensory transductions

Back 2

The transference of sensory events into changes in cell membrane potential

Front 3

Receptor potential

Back 3

A slow, graded electrical potential produced by a receptor cell in response to a physical stimulus

Front 4

Hue

Back 4

Dimension of light determined by wavelength

Front 5

Brightness

Back 5

The intensity of light

Front 6

Saturation

Back 6

Purity of light

Front 7

Saccadic movements

Back 7

The rapid, jerky movement of the eye used in scanning a visual scene

Front 8

Pursuit movement

Back 8

The slower, smoother movement of the eye when following a moving object, maintaining the image on the fovea

Front 9

Accommodation

Back 9

The alteration of the shape of the lens by ciliary muscles, focussing images of near or distant objects on the retina

Front 10

Retina

Back 10

The neural tissue and photoreceptive cells located on the inner surface of the posterior portion of the eye

Front 11

Rod

Back 11

Sensitive to light of low intensity

Front 12

Cone

Back 12

Maximally sensitive to one of three different wavelengths of light, encoding colour vision

Front 13

Fovea

Back 13

The central region of the retina, and contains only cones

Front 14

Optic disc

Back 14

A feature of the retina where the axons conveying visual information gather together and leave through the optic nerve, producing a blind spot

Front 15

Bipolar cells

Back 15

A bipolar neuron that conveys info from the photoreceptors to the ganglion cells

Front 16

Ganglion cells

Back 16

Receives visual information from bipolar cells, whose axons give rise to the optic nerve and carry visual information to the rest of the brain

Front 17

Horizontal/Amacrine cells

Back 17

Cells that transmit info in a direction parallel to the surface of the retina, thus combining messages from adjacent photoreceptors

Front 18

Lamellae

Back 18

Thin plates of membrane containing photopigments, found in the outer segment of photoreceptors

Front 19

Photopigments

Back 19

Special molecules embedded in the membrane of the lamellae, consisting of opsins and retinal

Front 20

Opsin

Back 20

Protein

Front 21

Rhodopsin

Back 21

Opsin found in rods, consisting of rod opsin and retinal

Front 22

Retinal

Back 22

A lipid, synthesized by vitamin A

Front 23

Dorsal lateral geniculate nucleus (LGN)

Back 23

A group of cell bodies within the lateral geniculate body of the thalamus

Front 24

Magnocellular layers

Back 24

One of the two inner layers in the LGN, transmits info necessary for the perception of form, movement, depth, and differences in brightness to the primary visual cortex (PVC)

Front 25

Parvocellular layers

Back 25

Four outer layers of the LGN, transmits info necessary for perception of colour and fine details to the PVC

Front 26

Koniocellular layers

Back 26

Sublayer found ventral to the other layers, transmits info from short (blue) wavelength cones to the PVC

Front 27

Calcarine fissure

Back 27

A horizontal fissure on the surface of the posterior cerebral cortex

Front 28

Optic chiasm

Back 28

A cross-shaped connection where the optic nerves join

Front 29

Receptive field

Back 29

The part of the visual field that an individual 'sees'

Front 30

Protanopia

Back 30

Hereditary visual disorder in which red and green is confused, which both look yellowish to those with this condition (red cones are filled with green opsin)

Front 31

Deuteranopia

Back 31

Red and green hues are confused, as the green cones are filled with red opsin

Front 32

Tritanopia

Back 32

Blue cones are either lacking or faulty, but since there are so few of them they don't affect visual acuity

Front 33

Simple cells

Back 33

Orientation-sensitive neuron whose receptive field is set up in an opponent fashion

Front 34

Complex cells

Back 34

Neuron that continued to respond to movement, no apparent inhibitory surround (movement detectors)

Front 35

Hypercomplex cells

Back 35

Neurons that respond to lines of a particular orientation, but have an inhibitory region at the end (or ends), meaning they can detect the location of ends of a line of a particular orientation

Front 36

Sine-wave grating

Back 36

A series of fuzzy, unfocused parallel bars

Front 37

Spatial frequency

Back 37

The relative width of the bands in a sine-wave grating, measured in cycles per degree of visual angle

Front 38

Retinal disparity

Back 38

A stimulus that produces images on slightly different parts of the retina on each eye

Front 39

Cytochrome oxidase (CO) blobs

Back 39

Contains wavelength (colour) sensitive neurons, part of the parvocellular system

Front 40

Extra-striate cortex

Back 40

The region of the visual association cortex that surrounds the striate cortex

Front 41

Dorsal stream

Back 41

A system of interconnected regions of visual cortex involved in perception of spatial location, beginning with the striate cortex and ending with the posterior parietal cortex

Front 42

Ventral stream

Back 42

A system of interconnected regions of visual cortex that are involved in the perception of form, beginning with the striate cortex and ending with the inferior temporal cortex

Front 43

Inferior temporal cortex

Back 43

Highest level of the ventral stream

Front 44

Posterior parietal cortex

Back 44

Highest level of the dorsal stream

Front 45

Colour constancy

Back 45

The relatively constant appearance of colours viewed under varying lighting conditions

Front 46

Cerebral achromatopsia

Back 46

Inability to discriminate among visual hues

Front 47

Visual agnosia

Back 47

An inability to perceive or identify visual stimulus, though visual details can still be detected and the person retains normal intellectual capacity

Front 48

Lateral occipital complex (LOC)

Back 48

A large region of the ventral stream of the visual association cortex that responds to a wide variety of objects and shapes

Front 49

Prosopagnosia

Back 49

The inability to recognize particular faces

Front 50

Fusiform face area (FFA)

Back 50

A region located in the inferior temporal, involved in the perception of faces

Front 51

Extra-striate body area (EBA)

Back 51

Region of the ventral stream that is specifically activated by photographs, silhouettes, or stick drawings or human bodies/body parts

Front 52

Para-hippocampal place area (PPA)

Back 52

Location in a region of the ventromedial temporal love that is activated by the sight of scenes or backgrounds

Front 53

Optic flow

Back 53

The relative movements between the visual elements of the environments and the observer

Front 54

Akinetopsia

Back 54

Inability to perceive movement

Front 55

Intra-parietal sulcus

Back 55

The end of the dorsal stream of the visual association cortex