The name is absent

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to MST activation comes from a recent fMRI study, which proposed that the human
homolog of VIP lies in the postcentral sulcus (Sereno and Huang 2006). Consistent with
this proposal, we observed a strong focus Of somatosensory activity in the mediolateral
regions of the postcentral sulcus (Fig. 7). However, the homology between monkey and
human parietal cortex is far from settled (Grefkes and Fink 2005), and other parietal
areas must also be investigated as possible anatomical sources for tactile responses in
MST.

In a meta-analysis of 57 functional imaging studies of S2, Eickhoff et al. (EickhOff,
et al. 2006a) found somatosensory activation in four Cytoarchitectonically defined
regions of parietal operculum (OP1-OP4), with the highest probability of activation in
OPl (putative 52). Consistent with this analysis, we also observed activation in each
cytoarchitectonie region, with the highest fraction of active voxels in OP1∕S2. There are
likely to be important functional differences between the cytoarchitectonie subdivisions
of the parietal operculum. In particular, 0P2 may be equivalent to PIVC, the
Parietoinsular vestibular cortex. Our study found strong Vibrotactile activation in
0P2∕PIVC, suggesting that multisensory convergence of tactile and vestibular
information may occur in this region. Vibration applied to the neck can induce changes
in steering of locomotion (Bove, et al. 2001) and perceived body orientation (Karnath, et
al. 1994), demonstrating the behavioral relevance of vestibular-tactile integration.
Additional studies examining the response of 0P2 to the tactile and vestibular cues
produced during natural behaviors, such as head movements (Petit and Beauchamp

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