オザキ　イサム   Ozaki Isamu   尾﨑　勇    所属   東邦大学  医学部 医学科    職種   研究員（寄付講座）
論文種別	原著
言語種別	英語
査読の有無	査読あり
表題	Tonotopic maps and short-term plasticity in the human auditory cortex
掲載誌名	正式名：International Congress Series ISSNコード：0531-5131
巻・号・頁	1270(C),pp.67-73
著者・共著者	Isamu Ozaki
発行年月	2004
概要	We showed tonotopic maps in the human auditory cortex based on the analysis of auditory evoked magnetic fields (AEFs) and rapid changes in tonotopic maps during auditory attention tasks. The location and strength of the N100m dipole for 400- and 4000-Hz tones were successively calculated before and at around the peak latency. In the right hemisphere, the current dipoles for 400 and 4000 Hz moved toward anterolateral direction before the N100m peak, showing parallel arrangement of the isofrequency bands. In the left hemisphere, the movement direction of 400-Hz dipoles was anterolateral, while that of 4000-Hz dipoles was lateral. This difference in the layout of isofrequency bands between right and left auditory cortices reflects distinct functional roles in auditory information processing such as pitch vs. phonetic analysis. In addition, when subjects tried to discriminate the differences in pitch or laterality, N100m amplitude increased. The N100m dipole distance between 400- and 4000-Hz tones was enlarged during pitch discrimination tasks especially in the right auditory cortex but was unchanged during laterality discrimination tasks. These dynamic changes in the N100m dipole presumably reflect a short-term plasticity in the primary auditory cortex. © 2004 Elsevier B.V.
DOI	10.1016/j.ics.2004.05.083