Chapter 6 Object Recognition Flashcards
object recognition 4 concepts
-precision: using the term perceive or recognize correctly
-perceive: seeing that is object
-recognize: identifying
what object is and what
is use for
- unity: we perceive a unified whole
- flexibility robust: recognizing objects despite shifts in orientation, lighting, occlusion
- memory bound: once we perceive an image, memories are triggered
hierarchical coding hypothesis
-we have neurons that detect specific features (like edges, corners) and other things and then gets put together to make up one object
EX: vertical edge->corners–>rectangular surface =table
grandmother cells..how likely this theory
- recognition arises from the activation of neurons that are finely tuned to specific stimuli
- we have a specific neuron in our brain that is specific for recognizing specific objects
ex: halle berry neuron
ensemble theories…how likely are these to be true
- Stimulus recognition is based on the collective activation of many neurons
- we have neurons that recognize multiple features and put them together into a single object
ex: specific hair, lips, face = grandma
Dorsal visual processing stream
- WHERE
- spatial perception
-bilateral PARIETAL lobe
ventral visual processing stream
- WHAT
- object perception and recognition
-bilateral TEMPORAL lobe
Is there a dissociation for what and where information in the auditory system?
- NO
- Ventral= identifying pattern/ WHAT
- Dorsal = WHERE/ sound location
Describe 2 lines of evidence supporting this theory (Dorsal and Ventral)
- lesion studies with monkeys
- Outcome of bilateral temporal lobe lesions : Difficulty discriminating shapes
- Outcome of bilateral parietal lobe lesions: Difficulty discriminating object location
agnosia
Inability to interpret sensations and hence to recognize things, typically as a result of brain damage
visual agnosia
- deficit in visual recognition
- trouble recognizing objects
- see all the details, but no idea what an object is
optic ataxia
- deficit in visual-manual guidance
- can identify the object and see where is located, but when trying to grab they can’t
- when not watching they can interact with the object
apperceptive agnosia
- difficulty in developing coherent percept
- Good at visual views of objects in typical views, but difficulty when object is in an unusual view/perspective
- Trouble when items are shadowed together or unusual orientation
integrative agnosia
-Subtype of apperceptive agnosia involving failure to integrate parts of an object into a coherent whole
- difficulty putting objects together
- cannot separate objects from each other
associative agnosia
-Cannot understand or assign meaning to objects, but can parse them
- Trouble identifying objects
- trouble giving meaning of the object
-able to see objects separately, but not able to name them
Which region of the brain is involved in face recognition? How is this region controversial?
- fusiform face area
- An area in the ventral temporal lobe that appears specialized to detect faces
- Some controversy on whether it’s a face specific area or an expert specific area
- this area like faces, but can also be activated when use to identify expert objects or when doing things one is an expert in
