COGS 101A Lecture Notes - Lecture 8: Ponzo Illusion, Canny Edge Detector, Retina
● Object Recognition
○ Ventral Pathway
■ Visual form agnosia
● Can’t recognize seen objects
○ Dorsal Pathway
■ “What where” deficit
● dorsal pathway damaged = not being able to see where an object
it
■ Where/ How/ “Action”
● DF
○ Temporal lobe damage
○ Couldn’t recognize where the mail slot was but when told
to mail a letter, was able to do so
■ Needed goal
○ Double Dissociation
■ One subject has damage to one area of the brain causes fcn A to be
absent, other subject has different section damaged means fcn B is
absent
○ Neuropsychology
■ Use double dissociation to figure out what sections of the brain do what
○ Experiments
■ Object discrimination
● Monkey shown an object and rewarded for recognizing it
(choosing the right one)
○ Temporal
■ When lesioned, monkey couldn’t learn again
○ Parietal
■ Could learn
■ Landmark discrimination
● Monkey choose the food contained next to cylinder to get food
○ Temporal
■ When lesioned, monkey could still learn
○ Parietal
■ Couldn’t learn
○ iClicker
■ Nick has temporal lobe damage, so he is more likely to tell two objects
apart
■ Where/how/ action pathway is called this because a person can fit an
object to an orientation when action is involved
○ Computational Level
■ What problem does it solve or overcome?
○ Algorithmic level
■ What steps does the system take?
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Document Summary
Dorsal pathway damaged = not being able to see where an object it. Couldn"t recognize where the mail slot was but when told to mail a letter, was able to do so. One subject has damage to one area of the brain causes fcn a to be absent, other subject has different section damaged means fcn b is absent. Use double dissociation to figure out what sections of the brain do what. Monkey shown an object and rewarded for recognizing it (choosing the right one) Monkey choose the food contained next to cylinder to get food. Nick has temporal lobe damage, so he is more likely to tell two objects apart. Where/how/ action pathway is called this because a person can fit an object to an orientation when action is involved. How is this physically instantiated in the brain or system. What are the neural correlates of object perception.