Computing Target Location

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Computing Target Location
In what coordinate frame do we plan our
movements? 1.) Visual target T 2.)
Representation of the End Effector ee 3.) The
idea of a difference vector from the ee to the
T. The target appears on the retina. The eyes
can move inside the orbit. The head can move and
so can the position of the shoulder joint.
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Gain fields from the PPC area 7a
pg 190 in the book. taken from Andersen et al
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Accumulation of errors. These movements were made
without visual feedback of the arm or hand.
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Very little change in cells activity as the
target and eyes move together
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Memory of the plan or target information.
Maintaining movement plan after a target
disappears
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Difference between the brain regions with respect
to loads. Kinimatics vs. Dynamics.
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Planning saccades vs. reaching movements.
R1 reach cue1 R2 reach cue2 same for S1 and
S2
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Planning movements away from a stimulus. 5d
fixation centered representation of the target
location.
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When there is a reach the cell only cares about
the reaching and not the saccade in the opposite
direction indicating that the monkey had been
planning a covert reach.
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planning the next movement in a sequence PPC
Looked at cells that increase activity durring a
delay period only for reaches not for saccades.
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