The name is absent

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imagery is an active process engaged by demanding tasks, making this possibility
unlikely: because there was no behavioral task for hand or foot stimulation in our study,
there was no reason for subjects to engage in imagery. Furthermore, it is highly unlikely
that over the hundreds of trials in our rapid event-related design, the subject would
reliably (and in a time-locked manner) engage in visual imagery of the stimulus or the
body part that was stimulated. Finally, it is also unlikely that imagining the visual
appearance of the hand evokes stronger responses in MST than imagining the visual
appearance of the foot, which is what was measured. Despite this evidence against an
imagery explanation, we cannot definitively rule out a contribution of visual imagery
Withoutadditionalstudies.

The second cognitive factor that we consider is attention. MT+ is part of the
"attentional network" that shifts spatial attention to exogenous cues (Beauchamp, et al.
2001; Corbetta, et al. 1998). Tactile stimuli might produce a shift in the focus of
attention to the body location of the stimulus. However, like visual imagery, shifting
attention is a resource-demanding process. As argued for imagery, without a task
requiring them to shift attention, it seems likely that subjects would habituate over the
Courseofthehundredsoftrialsofpassivestimulation.

We next consider perceptual processes that may explain MST activation. We
now turn to more likely processes. The first perceptual process that may be an
explanation for tactile MST activity is spatial transformation. An fMRI study suggests
that anterior regions of MT+ (likely MST) code space in a Spatiotopic (body centered) as
opposed to retinotopic reference frame (d'Avossa, et al. 2∞7). MST might be part of a

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