psyc 355 module 6 audio transcript flashcards

Flashcards about retinofugal projections, striate cortex, extra-striate cortical areas, auditory cortex and vestibular system

What are retinofugal projections?

Axons of ganglion cells that form the optic nerve

What are the two main targets of retinofugal projections?

The lateral geniculate nucleus (LGN) in the thalamus and non-thalamic targets

Where does the optic nerve form?

The optic disc, a region at the back of the eyeball also known as the blind spot

What occurs at the optic chiasm?

A partial crossing of axons where axons from the nasal retina cross

What is a hemifield?

Half of the visual field

How is visual information from each hemifield processed in the brain?

Left hemifield information is processed by the right side of the brain, and vice versa

What is the binocular visual field?

The region where the left and right hemifields overlap

What is the lateral geniculate nucleus (LGN)?

A region of the thalamus where axons of ganglion cells synapse

What are the optic radiations?

A bundle of white matter formed by axons of neurons from the LGN on their way to the visual cortex

Which layers of the LGN do axons from ganglion cell P-type project to?

Layers 3, 4, 5, and 6

Which layers of the LGN do axons from ganglion cell M-type project to?

Layers 1 and 2

Which layers of the LGN do axons from ganglion cell non-M, non-P project to?

Layers K-1 to K-6

What role does the hypothalamus play as a target of retinofugal projections?

Biological rhythms, including sleep and wakefulness

What role does the pretectum play as a target of retinofugal projections?

Control the size of the pupil and certain types of eye movement

What role does the superior colliculus play as a target of retinofugal projections?

Control the orientation of the eyes in response to new stimuli

What is the striate cortex (V1)?

The first cortical target of visual information, located in the occipital lobe

What is retinotopic organization?

Adjacent cells of the retina project to adjacent cells in the LGN, which project to adjacent cells in V1

What are ocular dominance columns?

Stripes of neurons responding preferentially to input from one eye or the other in the striate cortex

What are blobs?

Patches of neurons in layer three of the striate cortex involved in visual processing

What are blobs made of?

Neurons sensitive to color

What is the dorsal stream involved in?

The analysis of visual motion and the visual control of action

What is the ventral stream involved in?

Our perception of the visual world and the recognition of objects

What is area MT (V5) specialized in?

Detecting motion of objects

What is area MST involved in?

Motion perception

What is V4 involved in?

Color perception

Which project area from V4 is specialized in color perception and face recognition

Area IT

What is the function of inner hair and other hair cells?

Detect the signal, while the outer hair cells amplify the signal

Which area of temportal lobe is similar in its structure to the striate cortex

Primary auditory cortex (A1)

What do the otolith organs detect?

Forces of gravity and tilt of the head

What do the semicircular canals detect?

Rotation of the head

What do otolithic organs detect in detail?

Head angle changes and linear acceleration

What do semicircular canals detect in detail?

Turning movement of the head and angular acceleration

Where do the axons from the vestibular nerve synapse?

Vestibular nuclei neurons and cerebellar neurons

What is the vestibulo-ocular reflex (VOR)?

Allows you to fixate on an object, even when you move your head