Aligning Vision and Proprioception 2 Inactivation of PMv or PMd with small injections of muscimol did not disrupt reaching movements significantly in the baseline condition. During prism adaptation however inactivation of the left PMv affected adaptation only to prisms that shifted the visual field to the left. Possibly indicating a role for PMv in the alignment of the difference vector with proprioception information, which is in agreement with results presented in section 14.1 were we saw PMv encoded the direction and distance of a target with respect to the hand regardless of hand orientation. Why would inactivation of the left PMv only cause problems when adapting to a left ward shifting prism?

Note that the right visual field is represented in the left hemisphere

Situation for prisms that shift to the left. The subject will miss the target to the left of the target, thus the target will be to the right of the fixation point, which is represented in the left hemisphere.

Spatial Neglect There were no problems if they cut just one optic tract, or the corpus callosum and anterior commissure, or the PPC on one side. However if they cut one optic tract, the corpus callosum and the anterior commissure they then saw a contralateral spatial neglect. B and C shows that the remembered target position moves from one hemisphere to the other with movement of fixation Gaffan and Hornak

Adaptation after prisms lasted for 4 days and actually improved hours after the session. Rossetti et al

Cerebellar damage prevents adaptation. PMV has reciprocal connections with the cerebellum via the thalamus, ION and basilar pontine nuclei, and damage to these areas causes similar results. Martin et al

Subjects made reaches in virtual 3d to targets without visual feedback of their finger in B. They then made reaches to the box seen in B with altered visual feedback 3 cm around the target such that their hand was displaced 6 cm to the left. C. Post-exposure reaching without visual feedback. D. Model predictions in a spherical coordinate frame with the origin between the eyes. Vetter et al

Subjects made reaching movements to one visual target. The visual mapping was then changed such that the seen finger position was = to [x-ay, y], that is the finger would appear shifted in the x direction in proportion to the distance along the y direction. 1. posture adducted degree abduction degree abduction Baraduc and Wolpert

Reaching with a 30 degree visual rotation. Krakauer et al