title: Role of the precuneus in the detection of incongruency between tactile and visual texture information: A functional MRI study.
abstract: Visual clues as to the physical substance of manufactured objects can be misleading. For example, a plastic ring can appear to be made of gold. However, we can avoid misidentifying an object׳s substance by comparing visual and tactile information. As compared to the spatial properties of an object (e.g., orientation), however, little information regarding physical object properties (material properties) is shared between vision and touch. How can such different kinds of information be compared in the brain? One possibility is that the visuo-tactile comparison of material information is mediated by associations that are previously learned between the two modalities. Previous studies suggest that a cortical network involving the medial temporal lobe and precuneus plays a critical role in the retrieval of information from long-term memory. Here, we used functional magnetic resonance imaging (fMRI) to test whether these brain regions are involved in the visuo-tactile comparison of material properties. The stimuli consisted of surfaces in which an oriented plastic bar was placed on a background texture. Twenty-two healthy participants determined whether the orientations of visually- and tactually-presented bar stimuli were congruent in the orientation conditions, and whether visually- and tactually-presented background textures were congruent in the texture conditions. The texture conditions revealed greater activation of the fusiform gyrus, medial temporal lobe and lateral prefrontal cortex compared with the orientation conditions. In the texture conditions, the precuneus showed greater response to incongruent stimuli than to congruent stimuli. This incongruency effect was greater for the texture conditions than for the orientation conditions. These results suggest that the precuneus is involved in detecting incongruency between tactile and visual texture information in concert with the medial temporal lobe, which is tightly linked with long-term memory.
authors.affiliation: Division of Cerebral Integration, National Institute for Physiological Sciences, Okazaki 444-8585, Japan; Department of Physiological Sciences, The Graduate University for Advanced Studies (Sokendai), Japan. Electronic address: kitada@nips.ac.jp.
authors.forename: Ryo
authors.initials: R
authors.lastname: Kitada
authors.affiliation: Department of Physiology, Osaka City University Graduate School of Medicine, Osaka 545-8585, Japan; Pathophysiological and Health Science Team, RIKEN Center for Life Science Technologies, Kobe 650-0047, Japan.
authors.forename: Akihiro T
authors.initials: AT
authors.lastname: Sasaki
authors.affiliation: Research Center for Child Mental Development, University of Fukui, Eiheiji 910-1193, Japan.
authors.forename: Yuko
authors.initials: Y
authors.lastname: Okamoto
authors.affiliation: ATR Brain Activity Imaging Center, Seika-cho 619-0288, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Kochiyama
authors.affiliation: Division of Cerebral Integration, National Institute for Physiological Sciences, Okazaki 444-8585, Japan; Department of Physiological Sciences, The Graduate University for Advanced Studies (Sokendai), Japan.
authors.forename: Norihiro
authors.initials: N
authors.lastname: Sadato
mesh_terms: D000293:Adolescent; D000328:Adult; D001931:Brain Mapping; D005260:Female; D006801:Humans; D008279:Magnetic Resonance Imaging; D008297:Male; D010296:Parietal Lobe / Q000000981:diagnostic imaging / Q000502:physiology*; D010775:Photic Stimulation; D010812:Physical Stimulation; D055698:Touch Perception / Q000502:physiology*; D014796:Visual Perception / Q000502:physiology*; D055815:Young Adult
keywords: Material; Multisensory; Orientation; Touch; Vision; fMRI