lecture 5: perceptual organisation, gestalt psychology, and face perception

What are the main components of low-level vision?

Low-level vision extracts local information about lines, bars, and edges.

What is the role of mid-level vision in perception?

Mid-level vision joins isolated features into larger groups, forming the basis for object recognition in high-level vision.

What do the ventral and dorsal streams in the visual brain represent?

The ventral ('what') stream is for object identification, while the dorsal ('where') stream processes visuo-spatial information.

What does 'No Strict Separation' mean in the context of visual processing?

It refers to the complex connectivity and lack of strict anatomical or functional separation between the ‘what’ and ‘where’ streams.

What is the main challenge in mid-level vision?

The challenge is how local information processed in V1 is grouped into larger, meaningful units due to ambiguities.

What principle do Gestalt psychologists emphasize regarding perception?

The principle that relationships between elements are critical for perception; the whole is greater than the sum of its parts.

List two principles of perceptual organization according to Gestalt psychology.

Principles of proximity and similarity.

What is the 'Face Inversion Effect'?

It refers to the disruption of processing fine details and relationships between features when a face is inverted.

What is prosopagnosia?

Prosopagnosia is the failure to identify or distinguish between faces, despite otherwise normal visual and cognitive abilities.

What does the norm-based code in face recognition represent?

Facial features are represented as deviations from the average face, highlighting distinctive features that define individuals.

What evidence supports the idea that face processing might be special?

Evidence includes the presence of special neurons in the inferotemporal cortex, reliance on holistic processing, and the phenomenon of prosopagnosia.