The name is absent

36

(59.9%) and 0P2 (59.8%) were significantly active, with a smaller fraction of active

voxels in OP3 (19.1%) and OP4 (21.7%).

Figure 7. Relationship between Cytoarchitectonically defined areas and somatosensory Vibrotactile
activation. A, Cytoarchitectonic regions in and near Sl from the Anatomy Toolbox (z=54 mm)
(Eickhoff, et al. 2005; Geyer, et al. 1999; Grefkes, et al. 2001). B, Average somatosensory activation
(orange-to-yellow color scale) under cytoarchitectonie boundaries (colored outlines). C,
Cytoarchitectonic regions in and near S2 (z=18 mm) (Eickhoff, et al. 2006a; Eickhoff, et al. 2006b). O,
Average somatosensory activations under cytoarchitectonie boundaries.

Discussion

These experiments demonstrate that simple Vibrotactile stimuli evoke robust
BOLD fMRI responses in MST but not in MT. A potential source for Vibrotactile responses
in MST is a projection from the ventral intraparietal area (VIP). In nonhuman primates,
VlP receives input from hand and arm regions of S2, and in turn

VIP projects to MST (Lewis and Van Essen, 2000). Connections from macaque VIP to MT
are much sparser than those from VIP to MST, perhaps reflecting the weaker
Vibrotactile responses in MT than MST observed in the present study. Although the
connectivity of human MST is uncertain, studies using diffusion tensor
fractography (Rushworth, et al. 2006) and functional effective connectivity (Peltier, et al.
2007) offer promising avenues of exploration. Additional support for VIP contributions

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