Central Visual Pathways Flashcards
How is Optic Chiasm different from Optic Nerve?
It hold incoming information from both the eyes.
Where do the retinal ganglion axons terminate?
dorsolateral geniculate nucleus of the thalamus.
What is the functional role of Pretectum?
It is the center for coordinating pupillary light reflex.
What did Hubel and Wiesel’s experiment reveal?
Visual stimuli encoding activity of a distinct
population of orientation-selective neurons responding to a particular preferred stimulus orientation. (Highest in Vertical and none in Horizontal)
Why must cortical neurons show selectivity for particular stimulus dimensions?
The receptive fields with stimulus specific properties match the statistical architecture of natural scenes and would therefore maximize the amount of information transferred with a minimum of redundancy
What do the Magnocellular and Parvocellular pathway constitute?
The retinogeniculate pathway to visual cortex layer 4
What happens when magnocellular and parvocellular pathways are damaged?
Magnocellular - inability to perceive motion
Parvocellular - visual acuity and color vision is impaired.
What is the difference between cerebral akinetopsia and achromatopsia?
Akinetopsia - deficit in motion perception
Achromatopsia - deficit in color perception
What are near and far cells in binocular disparity?
Group of neurons that lie beyond the fixation plane are known as far cells and that lie in front of the fixation plane are known as near cells to mediate stereoscopic depth perception
What do the dorsal and ventral stream pathways convey?
The dorsal pathway conveys spatial information for localizing objects and the ventral pathway conveys the physical features of the object for object recognition.
