2004 Fiscal Year Final Research Report Summary
Investigation of neuropsychological processes in music perception using magnetoencephalography.
| Project/Area Number |
15500330
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| Research Category |
Grant-in-Aid for Scientific Research (C)
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| Allocation Type | Single-year Grants |
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| Section | 一般 |
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| Research Field |
Biomedical engineering/Biological material science
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| Research Institution | Tokyo Denki University |
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Principal Investigator |
NEMOTO Iku Tokyo Denki University, Department of Information Environment Design and Integration, Professor, 情報環境学部, 教授 (40105672)
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| Co-Investigator(Kenkyū-buntansha) |
KAWAKATSU Masaki Tokyo Denki University, 情報環境学部, 講師 (50297587)
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| Project Period (FY) |
2003 – 2004
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| Keywords | music perception / magnetoencephalography(MEG) / backward masking / dissonant chords / melody perception / working memory / auditory 40 Hz response / N1m |
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| Research Abstract |
Our research has been done under the four main topics given below with brief descriptbion of the results.
(1)Auditory backward masking and MEG Auditory masking is considered to have significant bearing on musical perception through frequency selectivity and time resolution. Furthermore, it has been recently found out that the amount of backward masking is related to the development of language ability of children, which makes its research all the more important. We investigated MEG responses to stimuli causing backward masking. The results show for example that the N1m peak amplitudes demonstrate some nonlinear relationship between the internal responses to signal and to masker. We are constructing a model for this phenomenon utilizing the time window proposed for behavioral results of backward masking experiments.
(2)MEG responses to dissonant chords We found in particular, that for two pure tones with the minor second interval, evoked magnetic fields show higher frequency components (20-40Hz) superimposed on a DC component around 200-400 ms after the onset of the tones. We are looking for signal sources for these components using many subjects. We also note the similarity between this longer latency components with the evoked magnetic fields to 40-Hz modulated chirps or pure tones.
(3)Melody perception, working memory and MEG responses We prepared several phrases composed of three notes and presented them to subjects in a similar manner to experiments for investigation of working memory. The evoked magnetic fields were related to the difficulty in memory tasks imposed on the subjects.
(4)Phase synchronization in the MEG 40 Hz component This experiment is related to (2)as described. We measured the synchronization of the phases of 40 Hz component when the subject hears 250-500 Hz tone modulated 40 /s. A model describing the dynamics of the phase has been proposed.
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