Object Recognition Flashcards
What percentage of the neurones in the parietal cortex have receptive fields that exclude the fovea?
60%
What are the names of the two visual pathways?
Dorsal (where)
Ventral (what)
What stimulus do neurons in the parietal cortex respond to?
Variety including large objects, small objects
What do the receptive fields in the temporal cortex always encompass
Fovea
What versus where in the monkey visual cortex (pohl, 1973)
They found that the inferotemporal cortex is the where
Parietal cortex is the where
What do lesions to the inferotemporal cortex impair
Object recognition
What do lesions to the parietal cortex impair
Spatial recognition
What versus where: neuroimaging evidence (kohler et al (1995))
What did they do
Given two pics
Spatial location same/ different?
Object identity same/ different?
What v where: kohler results: what did they find in those with parietal cortex lesions
Hemispatial neglect and optic atoxia
What v where: kohler: results: what did they find in those with temporal cortex lesions
Visual agnosia
Deficit in recognising objects
What is apperceptive agnosia
Can’t perceive objects
Need more info to identify an object
Don’t have object constancy
What is object constancy
Can recognise objects from different angles
Describe how that links to the miller lyer illusions
Not sure but know what it is
What did the study by Henson et al (2002) look at?
Object recognition
FMRI adaptation > region in left fusiform cortex that represents objects in a viewpoint independent manner
What is integrative agnosia
Can’t see objects as a coherent whole (2 triangles and a square)
How would patients with integrative agnosia draw two squares and a triangle (kanwisher)
Lateral occipital complex combines features into shapes
What is associative agnosia
Can’t access semantic knowledge of objects
Can’t represent objects by their function
Describe the study by tanaka and Farrah (1993)
Looks at face perception
Faces are processed holistically
What is prospoagnosia
Can’t recognise faces
Can recognise common objects
Can recognise people from their voices
What did kanwisher suggest
The fusiform face area- a face processing module
What would suggest that the FFA has within category distinction
Sheep farmer with prospoagnosia
- failed to recognise familiar faces
- could recognise individual sheep from his flock
What are grandmother cells
Cells that respond preferentially to your grandmothers face
Computationally inefficient
Susceptible to error
Novel objects
Changed in the appearance if grandmother
What are the criticisms of the quiroga Study about Jennifer Anniston neurons in temporal cortex
Small subset of neurons recorded from a small set of stimuli tested
Cell also responses to the word Jennifer Anniston
What the ensemble theory
Object recognition results from activation across complex feature detectors
Granny recognised when these higher order neurons are activated
