AIP shows fMRI adaptation for real grasping

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AIP shows fMRI adaptation for real grasping
SFN, ATLANTA, October 16, 2006
Greg Króliczak, Derek Quinlan Teresa McAdam
Jody Culham

• CIHR Group in Action Perception
• Department of Psychology
• University of Western Ontario
• London, CANADA

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Object and grip selectivity in macaque AIP
Visually-guided hand manipulation
Murata et al. 2000. J Neurophysiol.
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Putative human equivalent
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(Grill-Spector et al., 1999. Neuron)
Grill-Spector, Henson Martin (2006) TRENDS in
Cognitive Sciences
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• Current study
• 1) Does AIP encode the object?
• If so, AIP would show fMR-A for repeated
  objects.
• fMRI evidence suggests that AIP encodes the end
  goal of the action (cf. Hamilton Grafton, 2006,
  J Neurosci.)

• 2) Does AIP encode the grasp?
• If so, AIP would show fMR-A for repeated grasps
• Neurophysiological evidence suggests AIP encodes
  the grasp (Murata et al. 2000. J Neurophysiol.)
• But Two-Streams hypotheses suggests that the
  dorsal stream, including AIP, has no memory (cf.
  Goodale Milner, 1992 2005)

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4 Tesla MRI scanner (Varian, Palo Alto, Siemens)
Robarts Research Institute, London, Ontario,
CANADA
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GRASPARATUS II
Octagonal cylinder covered with Velcro
Shield
Object
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GRASPARATUS II
Octagonal cylinder covered with Velcro
Shield
Object
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GRASPARATUS II
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Stimuli NOVEL 3D Objects
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(No Transcript)
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DESIGN
Different Object
Same Object
Same Grasp
Different Grasp
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ROI contrast Grasping - Reaching
Same Object Same Grasp
1
Different Object Reach Out
Same Object Different Grasp
1
-
4 x
Different Object Same Grasp
1
AIP
Different Object Different Grasp
1
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Single Subjects - ROI Analysis in AIP (G-R)
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Single Subjects - ROI Analysis Left AIP (G-R)
2.5
2
1.5
Activation (Beta Weights)
1
0.5
0
Conditions
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Single Subjects - ROI Analysis Left AIP (G-R)
2.5
2
1.5
Activation (Beta Weights)
1
0.5
0
Conditions
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Single Subjects - ROI Analysis Right AIP (G-R)
2
1.5
1
Activation (Beta Weights)
0.5
0
Conditions
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Single Subjects - ROI Analysis Right AIP (G-R)
2
1.5
1
Activation (Beta Weights)
0.5
0
Conditions
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RFX (G-R)
Left AIP
Right AIP
Z 49
Z 46
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Left AIP RFX (G-R)
Z 49
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Right AIP RFX (G-R)
Z 46
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Discussion
The results consistent with Shmuelof Zohary
(2005) Neuron
Participants watched repeated video clips!

• BUT
• The two streams model suggests that the dorsal
  stream has no memory it is crucial to study real
  actions
• Mirror-neuron responses may differ from
  grasp-selective responses in AIP
• Viewing a grasping hand may activate intentions
  to grasp which disappear gradually with repeated
  clips.

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Behavioral evidence The dorsal stream has no
memory 1) Garofeanu et al. 2005 grasping
functional objects in a repetition priming
paradigm 2) Cant et al., 2005 repeated grasping
of abstract objects in movement precuing
paradigm No improvement in RT, but no kinematics
measured
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Summary
Our results support the idea that the dorsal
stream mediates visually-guided actions. BUT,
contrary to claims that dorsal stream has no
memory (Goodale Milner, 1992, 2005), we found
evidence suggesting that
1) some information related to objects and/or
visuomotor transformations - is stored in AIP
(and/or its related networks), and 2) this
information is used for grasp planning and/or
programming if similar grasping kinematics can be
repeatedly utilized.