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IfsTsmsishomologoustomacaquesTpjtshouldalsohavesimiIarfunctionaI
properties, above and beyond simply responding to the same three sensory modalities.
We used previous electrophysiological and fMRI studies of macaque STP as a gauge to
compare the functional properties of macaque STP with the functional activation of the
human STS as measured in this study; simultaneous electrophysiological and fMRI
studies have shown good correlation between mùItiunit activity, local field potentials
and the BOLD response (Logothetis, et al. 2001). Retinotopy in macaque STP, as
measured with fMRI, is relatively crude (Nelissen, et al. 2006). Receptive fields of single
units in STP are large; most are limited to the contralateral visual field but about a third
also respond to the ipsilateral visual field (Hikosaka, et al. 1988). This would predict a
significant ensemble BOLD fMRI response for ipsilateral stimulation, and a larger
response for contralateral stimulation. This is exactly the BOLD signal we recorded from
STSms: ipsilateral responses were significantly greater than zero, but significantly
weaker than the response to contralateral visual stimulation. Macaque STP shows a
significant fMRI response to moving compared with static stimuli (Nelissen, et al. 2006)
and visually-responsive macaque STP neurons are best activated by moving stimuli
(Bruce, et al. 1981; Hikosaka, et al. 1988). Consistent with this finding, we observed
significantly greater responses to moving compared with stationary stimuli in STSms, .
with only a weak response to static images. Macaque STP shows only a weak BOLD
preference for shapes compared with scrambled shapes (Nelissen, et al. 2006) and
single STP neurons show little or no selectivity for shape (Bruce, et al. 1981; Hikosaka, et
al. 1988). This matches our finding of no significant difference between real arid