chapter 4 Flashcards
(33 cards)
1
Q
optic chiasm
A
- location in the optic tract where the optic nerve from each eye splits in half
- nasal retinae cross over
- temporal retinae stay on the same side
2
Q
optic tract
A
- extension of the optic nerve starting at the optic chiasm, continuing into the brain
3
Q
contralateral representation of visual space
A
- left visual world goes to the right side of the brain
- right visual world goes to the left side of the brain
4
Q
ipsilateral organization
A
- same side organization
- temporal retina project to the same side of the brain
5
Q
lateral geniculate nucleus (LGN)
A
- bilateral structure (one in each hemisphere) in the thalamus
- receives information from the optic nerve
- sends information to the visual cortex
6
Q
magnocellular layers
A
- layers of the LGN
- large cells, receive input from M ganglion cells
7
Q
parvocellular layers
A
- layers of the LGN
- small cells, receive input from P ganglion cells
8
Q
koniocellular layers
A
- layers of the LGN
- very small cells, receive input from K ganglion cells
9
Q
parasol retinal ganglion cells (M cells)
A
- project to the magnocellular layer of the LGN
- high sensitivity to light
10
Q
midget retinal ganglion cells (P cells)
A
- project to parvocellular layers
- sensitive to wavelength, low light sensitivity
11
Q
bistratified retinal ganglion cells (K cells)
A
- project to the koniocellular layer
- sensitive to wavelength, low light sensitivity
12
Q
superior colliculus
A
- structure at the top of the brain stem, beneath the thalamus
- controls eye movements
13
Q
smooth pursuit eye movements
A
- voluntary tracking movements
14
Q
saccades
A
- most common/raid eye movements
- sudden eye movements, looking from one object to another
15
Q
primary visual cortex (V1)
A
- area of the cerebral cortex, located in the occipital lobe
- receives input from the LGN
- early visual processing
16
Q
retinotopic map
A
- point by point relation between the retina and V1
17
Q
cortical magnification
A
- allocation of more space in the cortex to some sensory receptors than others
- fovea has a larger cortical area than the periphery
18
Q
simple cells
A
- V1 neurons
- respond to particular orientations
19
Q
orienting tuning curve
A
- graph demonstrating typical response of a simple cell to stimuli or different orientation
20
Q
complex cells
A
- neurons in V1
- respond to a variety of stimuli across different locations
21
Q
end stopped neurons
A
- neurons that respond to stimuli that end within the cells receptive field
22
Q
ocular dominance column
A
- column within V1
- made up of neurons that receive input from only the left or right eye
23
Q
orientation column
A
- column within V1
- made up of neurons
- orientation of shape
24
Q
hypercolumn
A
- 1mm block of V1
- contains the ocular dominance and orientation columns for a particular region in visual space
25
blobs
- group of neurons within V1
- sensitive to color
26
interblobs
- group of neurons
- sensitive to orientation in vision
27
extrastriate cortex (secondary visual cortex)
- collective term for visual areas in the occipital lobe other than V1
28
V2
- second area in the visual cortex that receives input
29
ventral pathway
- midget and bistratified retinal ganglion cells
- visual cortex, inferotemporal cortex, temporal lobe
- "what" object identification and color vision
30
dorsal pathway
- parasol retinal ganglion cells
- visual cortex, parietal lobe
- "where" location of objects/movement
31
object agnosia
- deficit in identifying and recognising objects even though vision remains intact
32
inferotemporal cortext
- region in the temporal lobe
- receives input from the ventral visual pathway
- object identification
33
contralateral organization
- opposite side organization
- nasal retina project to opposite sides of the brain
