Neurophysiology - Lecture 16 & 17

The distance between two crests or troughs (peak to peak measurement)

Filled with a jelly like fluid, refracts light onto the retina

Where the optic nerve leaves the eye, causes a blind spot

Where accomodation occurs

Center of the retina, focused vision, where light falls when looking straight ahead

Located at the center of the macula, dense # of photoreceptors

A fat lens is a result of ciliary muscles ______ and is used to see _____________.

A flat lens results when ciliary muscles _______ and is used for seeing ___________.

As aging occurs the lens _______, so it is harder for the lens to go _______, which impairs _________ vision.

Nearsightedness, also known as ________, is corrected by a ________ lens to reduce refractive power

__________, or farsightedness, is corrected by a ______ lens to add refractive power.

This condition is corrected by an asymmetric lens to compensate for the asymmetry of the eye's lens.

Increased fluid pressure in the eye causing optic nerve damage and eventually death resulting in blindness

The cones degenerate, central vision is lost, but peripheral vision remains due to the rods.

Clouding of the lens and the lens must be surgically removed and replaced with a plastic one.

3 layers of the Retina

Ganglion Cells contain

Bipolar Cells contain

Peripheral vision, sensitive to light, high convergence and motion detection

Central vision, sensitive to color, low convergence and fine discrimination

Cones are more concentrated at the _____________

Rods are concentrated more heavily ______________ the fovea

Rods and cones constantly regenerate this protein, because one it changes, it falls off of the receptor

3 types of cones

After about __ minutes in the dark, the rods are more sensitive than the cones

On-center and off-center receptive fields ________ boundaries between light and dark.

Ganglion cells responsible for fine detail. Have small receptive fields, sustained APs and color opponent cells

Ganglion cells than are responsible for movement. Have large receptive fields, are sensitive to low contrast and have fast AP.

Red/green type color opponent ganglion cells are ______ while blue/yellow are ________.

Why do we have parallel processing in the visual system?

mixed info from both visual fields

nasal visual fields cross over at the

same information from one visual field travels along the

Why do we have binocular vision and what does it allow for?

Can use two images taken from slightly different angles and present them next to each other, producing depth perception in once focused image

2 pictures taken from slightly different angles and overlayed. One image is presented to each eye through color filtering glasses, which allows depth perception in a flat field.

Responsible for pupillary light reflex and moves head to orient to a visual image.

__________ layers take info from P-type while ____________ layers take info from m-type

Lateral Geniculate Nucleus organization (dorsal to ventral)

The major input to the LGN is the _________ cortex and the rest of the brain.

Project from layer 1 & 2 of LGN to layer IVCalpha

Project from layers 3-6 of LGN to layer IVCbeta

______ visual cortex cells respond strongly to a given orientation.

_______ visual cortex cells respond strongly to movement in a direction

5 things the primary visual cortex is responsible for.

In the extrastriate cortex, the _______ is the 'where' pathway, so motion is analyzed.
________ is the 'what' pathway, detail and color are analyzed.

Damage to V4, loss of color vision (only see black and white), subjects describe the world as depressing and food as unappetizing and hard to taste.

The eyes use the amount of light on the retina to help judge if an area is ________. All other colors are then compared to this baseline _______ color.

Inability to identify common items, but may be able to copy drawing of items and draw items from memory

Inability to recognize faces, including close family and themselves. Damage to IT and the Fusiform Face Area.

Damage to area MT of the brain; loss of ability to perceive motion, though perception of objects is intact

Perception of movement when none exists

Perception of motion in a stationary stimulus after viewing a moving stimulus. Occurs in area MT

Biological motion is the perception of motion related to living things. This involves the ________ __________ Sulcus

When shown a still that suggests motion, people remember the motion as being ______ along than it actually is. This activates brain areas ___ and ____

Apparent and real motion occur in _____ & _______ (areas of visual cortex)