title: Tactile priming modulates the activation of the fronto-parietal circuit during tactile angle match and non-match processing: an fMRI study.
abstract: The repetition of a stimulus task reduces the neural activity within certain cortical regions responsible for working memory (WM) processing. Although previous evidence has shown that repeated vibrotactile stimuli reduce the activation in the ventrolateral prefrontal cortex, whether the repeated tactile spatial stimuli triggered the priming effect correlated with the same cortical region remains unclear. Therefore, we used event-related functional magnetic resonance imaging (fMRI) and a delayed match-to-sample task to investigate the contributions of the priming effect to tactile spatial WM processing. Fourteen healthy volunteers were asked to encode three tactile angle stimuli during the encoding phase and one tactile angle stimulus during the recognition phase. Then, they answered whether the last angle stimulus was presented during the encoding phase. As expected, both the Match and Non-Match tasks activated a similar cerebral network. The critical new finding was decreased brain activity in the left inferior frontal gyrus (IFG), the right posterior parietal cortex (PPC) and bilateral medial frontal gyri (mFG) for the match task compared to the Non-Match task. Therefore, we suggest that the tactile priming engaged repetition suppression mechanisms during tactile angle matching, and this process decreased the activation of the fronto-parietal circuit, including IFG, mFG and PPC.
authors.affiliation: Biomedical Engineering Laboratory, Graduate School of Natural Science and Technology, Okayama University Okayama, Japan.
authors.forename: Jiajia
authors.initials: J
authors.lastname: Yang
authors.affiliation: Biomedical Engineering Laboratory, Graduate School of Natural Science and Technology, Okayama University Okayama, Japan.
authors.forename: Yinghua
authors.initials: Y
authors.lastname: Yu
authors.affiliation: Biomedical Engineering Laboratory, Graduate School of Natural Science and Technology, Okayama University Okayama, Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Kunita
authors.affiliation: Intelligent Robotics Institute, School of Mechatronical Engineering, Beijing Institute of Technology Beijing, China ; Key Laboratory of Biomimetic Robots and Systems, Ministry of Education China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Huang
authors.affiliation: Biomedical Engineering Laboratory, Graduate School of Natural Science and Technology, Okayama University Okayama, Japan ; Key Laboratory of Biomimetic Robots and Systems, Ministry of Education China.
authors.forename: Jinglong
authors.initials: J
authors.lastname: Wu
authors.affiliation: Human Brain Research Center (HBRC), Kyoto University Graduate School of Medicine Kyoto, Japan.
authors.forename: Nobukatsu
authors.initials: N
authors.lastname: Sawamoto
authors.affiliation: Human Brain Research Center (HBRC), Kyoto University Graduate School of Medicine Kyoto, Japan.
authors.forename: Hidenao
authors.initials: H
authors.lastname: Fukuyama
keywords: delayed match to sample task; fMRI; priming effect; tactile spatial working memory