LGN to 10/10

LGN sends info to

The primary visual cortex (6)

What does retinotopically organized mean in terms of Visual Cortex 6?

Neighboring cells tend to receive info from multiple nearby ganglion cells

It’s like a fMRI machine. corresponds to visual field

The V1 cells receptive fields are _____ compared to LGN fields

Bigger

What is another name for a simple cell?

Bar or edge detector

What are the functions of simple cells VI?

They locate smaller stripes, orientation and location, width, bar, edge

What is the process for a simple cell neuron VI?

It's like a circuit. Each ganglion cells goes to subsequent receptor. Light on retina → Ganglion cell → combine with 2 others to make a Simple cell neuron

What is a complex neuron?

A complex neuron is a bunch of simple cell neurons VI tract the movement of a bar if it is moving from side to side across the retina

What is the definition for a complex neuron?

Multiple simples neurons make up one VI complex neuron

What happens when the lens on your eye gets flatter/thin?

you are seeing something in the far distance

FLAT - FAR

What happens when the lens gets round/globular on your eye?

you are seeing something in near focus, something closeby by. ROUND - REAR (BUTT)

What is the process of light entering eye

Light → Ganglion cells → Amacrine Cells → Bipolar cells → Photoreceptors HYPERPOLARIZED. Closes Na+ channels

What is the process to get visual info from eye? from photoreceptor to visual cortex

Photoreceptors → Bipolar cells (ON/OFF CENTER) - light on center/surround → glutamate release and it is DEPOLARIZED, inhibits off surround/off center → Ganglion Cells → Nerve Optic fibers → Optic Nerve where Optic Disc is → Optic Chiasm → Optic Tract → Lateral Geniculate Nucelus (form optic radiation) → Primary Visual Cortex (VI)

What photoreceptor is responsible for rhodopsin

rods (scotopic)

What photoreceptor is responsible for photosopin?

cones (photopic)

What are the functions of the bumps and ridges of the pinna?

modify sound (suppress/enhance), human speech detector and alerts body of direction and distance of noise

parvocellular

fine, details for cones. colors, small receptive fields

magnocellular

depth and motion, rods, large receptive fields

ocular dominance slab/column

vertical column neurons in one eye. Adjacent → other eye. Same receptive field

prefer one eye over the other

orientation column

→ vertical column of neurons that respond -. rod shaped stimuli particular orientation

what are the 3 different types of maps?

dominance, location, and orientation

How many layers are in the LGN?

6

V1 → V2

→ V2 combined information from multiple V1 neurons to build complex representations

→ Textures

→ Multiple actual features and some illusionary features

What are V2, V3, V5?

They are all on the same side

What are V1, V4, and V6?

All on different sides

What are the dorsal pathways?

location: V1 – V5/MT – Posterior parietal cortex

What are ventral pathways?

identification: V1 – V2 – V4 – IT

V2 → V4

V4 neurons respond to complex radial and concentric stimuli

→ Wavelength (color) specific receptive fields

V4 → IT

Inferior temporal cortex responds to complex shapes, sensitivity to color and texture

→ Facial recognition (fusiform face area)

→ Prosopagnosia

or “face-blindness”

V1 → V5

→ V5 (medial temporal lobe) neurons perceive speed and direction of moving stimulus

→ Motion blindness

V5 → Posterior parietal cortex

▪ V5→Posterior parietal cortex

→ Neurons tuned to spatial location of objects

→ Planned movements, visuomotor transformation

Lesions in the parietal cortex

Hemi-spatial neglect

What layers of LGN are parvocellular?

layers 3-6

what layers of LGN are magnocellular?

layers 1-2