Action perception - HLP3 Flashcards
Why is action perception important? (5)
- understand the actions and intentions of others
- threat detection
- positive or negative action?
- building alliances
- interact with potential mates
What are cells in V4 and cells in V5 particularly sensitive to?
V4 = colour
V5 = direction
Where does visual information go after the eye? (3)
LGN –> V1 –> along to the V5
What are some properties of V5 cells? (4)
- larger receptive fields than V1
- sensitive to moving stuff, direction and speed
- contains a retinotopic map of the visual world
- microstimulation of directionally sensitive ones biases perception of motion in that direction
Where is the V5 connected to?
the medial superior temporal cortex
What are medial superior temporal cortex cells sensitive to? (4)
- translation
- expansion
- contraction
- rotation
What are the 6 different percepts from biological motion stimuli?
- actions
- hand actions, facial actions, speech
- gender
- emotion
- body weight
- identity
What happens when you show people biological motion dots moving in the same way but from different starting points?
Don’t perceive them as a person
Where is there activation when perceiving a person in biological motion stimuli?
posterior superior temporal sulcus (pSTS)
What can improve biological motion recognition?
sound
Which children don’t preferentially observe biological motion?
with autism
What other interesting thing can people derive from biological motion?
emotion
When is there STS activation in terms of biological motion? (3)
- observing it
- imagining it
- facial motion
where in the brain responds to rigid, non-articulated motion?
middle temporal gyrus
What happens as you go further down the STS?
responds more to the articulated nature of moving human stimuli
What are 3 study results showing when the hMT/V5 is active?
- more when viewing moving squares than stationary ones
- more when illusionary motion compared to no illusionary motion
- more when a figure shows implied motion (also STS activation)
Where does integration of form and motion happen? What will cells there respond to?
within the superior temporal sulcus - the cells will respond to a specific combination
What do many monkey STS cells respond to?
linking implied motion to walking direction
What is more likely to be happening than grandmother cells?
population coding of actions - output of multiple cells with different perception functions
What do STS cells not specify to? (4)
lighting, size, position in space, instance
What types of coding are there in STS cells? (3)
- view-dependent
- view-independent (allocentric)/ object-centred
Which brain regions respond to bodies? Where are they close to?
EBA and FBA
close to face regions
what is the hierarchy of object and body response size?
whole bodies > body parts > face parts > other objects and object parts
What does disruption of the occipital face area impair?
face processing
