PSY 323: Receptive Fields

Receptive fields

Region on retina that connects to a single cell further along the visual pathways

Each + is an excitatory location on retina

True

Each - is an inhibitory location on retina

True

On center vs Off center

The excitatory/inhibitory layout of receptive fields is called

Lateral Inhibition

Lateral Inhibition allows receptive fields to detect changes in

brightness

Line & Edge Detection

A receptive field detects a feature when its response \n changes in the presence of that feature

Receptive fields are a mechanism to identify all of the lines and edges in a scene

True

Receptive fields will respond most vigorously when their size matches the size of the stimulus

True

Strong Positive Response

Looks Bright

More Negative Response

Looks Dimmer

Visual pathways

•80% of Optic Tract heads here \n •Circular receptive fields with increased contrast \n •Reticular Activating System increases flow at higher \n arousal

Lateral Geniculate Nucleus

Retinotopic Mapping

Each layer is a map of entire ½ retina

Adjacent regions on retina connect to adjacent regions in LGN

Same region on retina is lined up vertically across layers