Parallel Processing Flashcards
When does the segregation between layers begin?
Ganglion cell layer
What input do the four dorsal LGN layers receive?
Midget parvocellular ganglion cells
What input do the two ventral LGN layers receive?
Parasol magnocellular ganglion cells
What layers send to layer IV-c beta?
Parvocellular
What layers send to IV-C alpha?
Magnocellular
Dorsal stream
Contains magnocellular input and is destined for the posterior parietal cortex
Ventral stream
Contains parvocellular input and is destined for the inferior temporal cortex
Which cells transmit a red-green color opponent signal
Midget ganglion cells
Which cells are sensitive to high spatial and low temporal frequencies
Midget ganglion cells
Which g cells have smaller receptive fields
Midget ganglion cells
Which cells have smaller cell bodies and dendritic trees
Midget ganglion cells
Which cells have a slower axonal conduction
Midget ganglion cells
Which cells synapse in 6, 5, 4, and 3 in the LGN
Midget ganglion cells
Which cells make up 10% of the ganglion cell population
Parasol ganglion cells
Which cells transmit an achromatic signal
Parasol ganglion cells
Which cells are sensitive to low spatial, high temporal frequencies and motion
Parasol ganglion cells
Which cells have the largest receptive field
Parasol ganglion cells
Which cells have larger cell bodies and large dendritic trees
Parasol ganglion cells
Which cells have faster axonal conduction
Parasol ganglion cells
Which cells synapse in layers 1 and 2 of the LGN
Parasol ganglion cells
Which cells comprise of 8% of the ganglion cell population
Bistratified ganglion cells
Which cells transmit a blue yellow color opponent signal
Bistratified ganglion cells
Which cells synapse in the interlaminar regions of the LGN
Bistratified ganglion cells
Spatial frequency
Level of detail contained per degree of visual light, measured in cycles/degree
Transient response
a response is shown only during stimulus abrupt on and off
Linear response
Total response of the cell is the sum of its response to the sub-parts of the stimulus
Null position
When the grating is placed such that half the light stripe falls on the center and the other half on the surround to get a neutralized response
Lesion in what region would cause reduced sensitivity to contrast at high spatial frequencies?
Dorsal layers, parvocellular system
Lesion in what region would cause reduced wavelength-based discriminations with color perception?
Dorsal layers, parvocellular system
Lesion in what region would cause reduced sensitivity to contrast at low spatial frequencies
Ventral layers, magnocellular
Lesion in what region would cause severe reduction in detection of high temporal frequency flicker?
Ventral layers, magnocellular syystem
Lesion in what region would leave color vision in tact?
Ventral layers, magnocellular system
Isoluminant gratings
Isolates the magnocellular and parvocellular layers with alternate bars of different chromaticities of the same luminance
Which system detects isoluminance
Parvocellular
Chromaticity
Combination of hue and saturation
Primary open angle glaucoma
Chronic progressive optic neuropathy typically associated with an elevation in IOP
Perimetric tests
Measures relative sensitivity of peripheral vision
Which neurons are affected first in glaucoma?
Magnocellular neurons (larger axons)
What stimulus is used in frequency doubling perimetry?
Low spatial frequency, high temporal frequency, with a rate of flicker of 15Hz
