L12: Vision 2 Flashcards
Who created the processing streams?
Milner and Goodale 1993
What does neuroimaging reveal?
object category and specific acitivty in ventral system
What is the fusiform gyrus?
face area
What is the grandmother cell?
Refers to neuron that would only respond to meaningful stimulus such as their grandmother (Hubel & Wiesel)
What is visual agnosia?
inability to recognise objects associated with damage to ventral cortical processing stream
What are the two types of visual agnosia?
apperceptive - perceptual
associative - semantic
What is bilateral parietal syndrome?
inability to interpret the totality of a scene (simultanagnosia)
inability to control visually guided movement (optic ataxia)
What did patient DF suffer from?
carbon-monoxide poisoning leading to diffuse posterior brain damage
What were the results of patient DF’s damages?
apperceptive agnosic: unable to discriminate object identity (effectively blind)
accurately reach and grasp objects
What does damage to the ventral stream cause?
Visual agnosias.
What does damage to dorsal processing regions lead to?
Spatial and action processing disorders (neglect and optic ataxia).
What did the evidence from patient DF suggest?
Dorsal pathways support visually guided actions and ventral pathways supports perception of object form and identity.
