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Sensory-motor integration. Bijan Pesaran. Visual response in PMv centered on hand. Graziano and Gross (1994). Visual response in PMv centered on hand. Graziano and Gross (1994). Invariant visual response in VIP. Duhamel et al (1997). Duhamel et al (1997). PRR neurons are eye-centered.
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Sensory-motor integration Bijan Pesaran
Visual response in PMv centered on hand Graziano and Gross (1994)
Visual response in PMv centered on hand Graziano and Gross (1994)
Invariant visual response in VIP Duhamel et al (1997)
PRR neurons are eye-centered Batista et al (1999)
Updating of response in PRR Batista et al (1999)
Mechanisms for encoding multiple variables • Centered tuning curve
Eye position influences visual response of 7a neurons Andersen et al (1985)
Gain field Tuning curve Mechanisms for encoding multiple variables • Centered tuning curve • Multiplicative encoding - gain field
Visual receptive fields in VIP partially shift with eye position Eye positions Avillac et al (2005)
Gain field Tuning curve Mechanisms for encoding multiple variables • Centered tuning curve • Multiplicative encoding - gain field • Partial shift encoding – intermediate reference frame
Eye position encoding • Widespread phenomenon throughout visual and motor cortices Peaked response Eye left Eye middle Eye right Response Target position
Eye position encoding • Difficulty addressing flanking responses Peaked response Flanking response Eye left Eye middle Eye right Response Target position
Gain model Shifting model
Nonlinear 3D geometry and muscle dynamics Geometry of visually-guided reaching • Eye-centered • Hand-centered • Relative position vectors T T-H T-E H H-E E E-H
Nonlinear 3D geometry and muscle dynamics Geometry of visually-guided reaching T T-H T-E H H-E E E-H What is code? Batista et al (1999) Eye-centered MIP PMd Pesaran et al (2006) PMv T-E Graziano et al (1997) Hand-centered T-H
- - + + Multiple reference frames Direct Transformation Eye-centered hand location • Direct visuomotor transformation • Supports Area 5 data (Buneo et al 2002) Nonlinear 3D geometry and muscle dynamics Eye-centered target location Hand-centered target location Motor output Serial Transformation Head-on-body position Body-centered hand position Eye-in-head position Head-centered target location Nonlinear 3D geometry and muscle dynamics Eye-centered target location Body-centered target location Hand-centered target location Motor output
Encoding relative position Nonlinear 3D geometry and muscle dynamics T Nonlinear muscle dynamics T-H T-E H H-E E E-H • Coordinating the hand and the eye • Eye-centered • Hand-centered • Relative hand-eye position • Vectors in abstract space Batista et al 1999 MIP PMd PMv Graziano et al 1997
1 2 Time (sec) 0 Cue Start Delay Hold Go Design reference frame task
1 2 Time (sec) 0 Cue Start Delay Hold Go Design reference frame task
Design reference frame task • Four initial eye positions
Design reference frame task • Four initial eye and hand positions
Design reference frame task • Four initial eye, hand and target positions • 111 PMd neurons and 48 MIP neurons
- - + + Sensory-motor transformations Serial Transformation Eye-in-head position Head-on-body position Body-centered hand position Head-centered target location Eye-centered target location Body-centered target location Hand-centered target location - +
Sensory-motor transformations Direct Transformation Eye-centered hand location - Hand-centered target location + Eye-centered target location Buneo et al. (2002)
Sensory-motor transformations Relative position Transformations Hand-centered target location + Eye-centered target location - Eye-centered hand location Relative location of hand and eye Hand-centered eye location - Hand-centered target location Eye-centered target location +
T T-H T-E H H-E E E-H Relative position particularly useful for coordination • Relative hand-eye position could be important for hand-eye coordination • Can map hand and eye onto each other • Computationally efficient • No need to code for all combinations of locations
T T-H T-E H H-E E E-H Relative position particularly useful for coordination • Relative hand-eye position could be important for hand-eye coordination • Can map hand and eye onto each other • Computationally efficient • No need to code for all combinations of locations
T T-H T-E H H-E E E-H Relative position particularly useful for coordination • Relative hand-eye position could be important for hand-eye coordination • Can map hand and eye onto each other • Computationally efficient • No need to code for all combinations of locations