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al. 2007) consistent with the so-called law of inverse effectiveness (Stein and Meredith
1993). In the present experiment, differences in auditory-tactile integration were not
observed for weak and strong tactile stimuli, possibly because all of the auditory stimuli
Werewellabovethreshold.
Double label studies show that projections into STP from parietal and temporal
lobe (carrying visual and auditory information, respectively) project to non-overlapping,
but often adjacent, patches of cortex (Hackett, et al. 2007; Seltzer, et al. 1996; Smiley, et
al. 2∞7). Functional responses in macaque STP are also unevenly distributed (Dahl, et
al. 2007). Consistent with these findings, in a high resolution fMRI study, human STSms
was observed to contain a patchy distribution of auditory, visual and multisensory
auditory- visual responses (Beauchamp, et al. 2004a). It is not clear whether macaque
STP or human STSms contains an additional, dedicated set of patches that respond
Preferentiallyto somatosensory stimulation, or whether somatosensory stimuli arrive in
STSms within the previously described auditory, visual and multisensory patches.
Homology between macaque STP and the human STS multisensory area
We hypothesized that if human STSms is the homolog of macaque STP, it should
share the same anatomical relationship with nearby identified areas, especially the
adjacent area MST. Detailed functional mapping showed that human STSms was located
just anterior to areas MST and MT, the same anatomical relationship that exists
between MT, MST and STP in macaque cortex (Fig. 5D) (Lewis and Van Essen 2000a).