The name is absent

34

Subjects were not required to make any behavioral responses to the
hand or foot Vibrotactile stimuli, and little activation Was observed in area MT. Because
MTis known to be modulated by spatial attention (Beauchamp, et al. 1997; O'Craven, et
al. 1997; Treue and Maunsell 1996), this raises the question of whether attending
specifically to the Vibrotactile stimulation would have resulted in increased activity in
MT. To address this question, in a control experiment on a single subject, stimulation
was delivered to different locations on the hand, and the subject made a behavioral
response depending on the pattern of stimulation. As shown in Figure 68, despite
attention directed to the site of stimulation, activation was observed in MST but not in
MT. ,^,' ;         .. 7 ". <          .       >            . '"          ' ■'          ; -       ' Ч ■' ■■■

A second question concerns the relative amplitude OfsOmatosensory and visual
responses in MST. Becausethevisual Iocalizer stimuli used a block design (20sof
stimulation), whereas the somatosensory experiment used a rapid event-related design
(2 s of stimulation), it was not possible to directly compare the amplitudes of response.
Therefore, in another control experiment on a single subject, a rapid event-related
design was used to present point-light displays of biological motion, a stimulus known to
evoke strong responses in MT+ (Beauchamp, et al. 2003; Peelen, et al. 2006). Consistent
with amplitudes observed in previous studies, MST showed a 0.54% response to moving
points. In the same subject, the MST response amplitude to Vibrotactile stimulation of
the contralateral hand was 0.26%, approximately one-half as large (Fig.

6C).          , '                ∙.                 .                                         ' .          ;                                    . ' ' ■            :• ■ ^?          ■' :              .

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