The name is absent

18

Introduction

The strategies used by the brain to integrate information from different sensory
modalities are a question at the heart of cognitive neuroscience. One view is that all of
sensory cortex is essentially multisensory (Ghazanfar and Schroeder 2006; Grefkes, et al.
2001). In support of this idea, functional neuroimaging studies have reported responses
to tactile stimuli in regions of occipital lobe traditionally regarded as purely visual
(Amedi, et al. 2001; Eickhoff, et al. 2005; Sathian, et al. 1997). More recently, two
groups have reported responses to tactile stimuli in area MT, a region considered to be
essential for processing visual motion (Blake, et al. 2004; Hagen, et al. 2∞2). In these
studies, responses in MT were observed to complex moving tactile stimuli: a brush
stroking the arm (Hagen, et al. 2002) ora rotating three-dimensional globe (Blake, et al.
2004). However, it is known that simply imagining a moving stimulus evokes activity in
MT (Goebel, et al. 1998) and that visual imagery in general is a powerful, specific
activator of visual cortex (lshai, et al. 2000; O'Craven and Kanwisher 2000). If in previous
studies subjects engaged in visual motion imagery (such as imagining the movement of
the brush as it traveled up and down the arm or the motion of the globe as it rotated),
activation in MT could have been an indirect result of visual imagery rather than a direct
result of somatosensory stimulation.

The standard MT localizers used in previous studies identify a region (which we
henceforth refer to as MT+) (Beauchamp, et al. 1997) that contains at least two distinct
areas, MT and MST. In nonhuman primates, MT and MST have distinct functional
specializations and different patterns Ofanatomical connectivity (Komatsu and Wurtz

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