Higher-Order Visual Processing

Two parallel pathways Retinogeniculostriate Recently evolved Used by mammals for perceptual processing Retinotectal Evolved long ago Used by mammals for control of gaze

temporal crescent

Retinogeniculostriate pathway retina



lateral geniculate nucleus of thalamus



striate cortex (visual cortex, V1)

Retinotectal pathway retina



optic tectum (superior colliculus)

Orientation Columns Ocular Dominance Columns

Receptive Fields

Retina + LGN + Visual Cortex + + + +

Receptive Fields

Retina + LGN + V1 + + + + + + -