W9: Form, Spatial and Motion Perception

Perception of form

• V1 Striate- V2 Extrastriate (ES) --> ventral stream of ES cortex

• Damage to ES cortex has led to understanding of regional functioning

• Visual Agnosia --> impaired object recognition

• Areas identified in inferior temporal and lateral occipital complexes activated by object categories

• Prosopagnosia- impaired facial recognition

^fusi-form face area (FFA) of temporal lobe (more active in the right)

Perception of space

*Mainly V5

• Retina, striate and extra striate cortex (ECS)

• Monocular but also binocular (stereopsis from retinal disparity) disparity in binocular- when neurons in V5 are most active (detecting change in visual field- movement)

• Disparity sensitive neurons found in the dorsal stream ESC

• Dorsal stream primarily involved, ending in posterior parietal lobe 

• 'Where' and 'How'- guides action

Perception of orientation and movement

• Neurons in striate cortex sensitive to orientation

• Extrastriate cortex responsible for movement perception

• V5 or MT (medial temporal region)

• Receives information from superior colliculus

• Medial Superior Temporal (MST) responsible for processing of optic flow across retina

N/A