Visual System and Neural Pathways

These flashcards cover key concepts from the lecture on the visual system and neural pathways, including receptive fields, types of bipolar and ganglion cells, and structures involved in visual processing.

Receptive Field

A small area of retina where light changes a neuron's firing rate.

Bipolar Cells

Cells in the retina that transmit signals from photoreceptors to ganglion cells, with ON and OFF types depending on their response to light.

ON Bipolar Cells

Bipolar cells that depolarize in response to light, effectively turning 'on' with light input.

OFF Bipolar Cells

Bipolar cells that hyperpolarize when light is shined onto a photoreceptor, effectively turning 'off' with light input.

Center-Surround Organization

The structure of bipolar and ganglion cell receptive fields, where the center and surround areas respond oppositely to light.

Ganglion Cells

Neurons in the retina that receive input from bipolar cells, responsible for transmitting visual information to the brain.

M-Type Cells

A type of ganglion cell with larger receptive fields, low-resolution vision, and rapid conduction of action potentials.

P-Type Cells

A type of ganglion cell comprising about 90% of the ganglion population, sensitive to color and small details.

Color Opponency

The phenomenon where the response to one color is canceled by showing another color in the receptive field surround.

Intrinsically Photosensitive Retinal Ganglion Cells (ipRGCs)

Ganglion cells that use melanopsin as a photopigment and are involved in circadian rhythms rather than fine pattern vision.

Optic Chiasm

The part of the visual system where optic nerve fibers cross from one side to the other, allowing for visual information processing.

LGN (Lateral Geniculate Nucleus)

The major relay center for visual information received from the retina, organized in distinct layers.

Ocular Dominance Columns

Alternating bands in the striate cortex where inputs from the left and right eyes are organized.

Cytochrome Oxidase Blobs

Pillars within the striate cortex that are associated with color processing and receive input from koniocellular pathways.

Magnocellular Pathway

A visual processing pathway that is sensitive to motion and guidance of actions.

Parvocellular Pathway

A visual pathway that analyzes fine object shape and small details.