QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

The Journal of Neuroscience, May 7, 2008, 28(19):4897-4903; doi:10.1523/JNEUROSCI.5031-07.2008

This Article Full Text Full Text (PDF) Supplemental Data Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Hirano, S. Articles by Onitsuka, T. Search for Related Content PubMed PubMed Citation Articles by Hirano, S. Articles by Onitsuka, T. Pubmed/NCBI databases Medline Plus Health Information Schizophrenia

 Previous Article  |  Next Article 

Brief Communications
Abnormal Neural Oscillatory Activity to Speech Sounds in Schizophrenia: A Magnetoencephalography Study

Shogo Hirano, Yoji Hirano, Toshihiko Maekawa, Choji Obayashi, Naoya Oribe, Toshihide Kuroki, Shigenobu Kanba, and Toshiaki Onitsuka

Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, Fukuoka 812-8582, Japan

Correspondence should be addressed to Dr. Toshiaki Onitsuka, Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashiku, Fukuoka 812-8582, Japan. Email: toshiaki{at}npsych.med.kyushu-u.ac.jp

Schizophrenia impairs many cognitive functions, and abnormalities in language processing have been proposed as one of the bases for this disorder. Previously, it was reported that different magnetoencephalography (MEG) patterns of the evoked oscillatory activity (eOA) of 20–45 Hz to speech and nonspeech sounds were evidence of a fast mechanism for the representation and identification of speech sounds in humans. The current study tested the hypothesis that the schizophrenics would show abnormal neural oscillatory activity, as measured by eOA, to speech and nonspeech sounds. Twenty patients and 23 control subjects participated in this study. MEG responses to speech and nonspeech sounds were recorded and eOA power and phase locking at 20–45 Hz were analyzed. Patients showed significantly delayed peak latencies of the eOA power and phase locking to speech sounds in the left hemisphere and to nonspeech sounds in the right hemisphere. Patients also showed a significantly reduced eOA power to speech sounds in the left hemisphere in 0–50 ms and a significantly larger eOA power to speech sounds in the left hemisphere in 100–150 ms. In addition, the analyses of the lateralization index revealed the pattern of hemispheric lateralization to be the opposite in patients. These results indicated that patients showed different characteristics of eOA compared with normal controls, probably related to deficits in a fast mechanism for identifying speech sounds. Moreover, the present study suggests that schizophrenia might be characterized by an opposite pattern of hemispheric lateralization in auditory evoked oscillations.

Key words: evoked oscillatory activity; schizophrenia; speech sounds; magnetoencephalography; lateralization; wavelet transform

---

Received June 14, 2007; revised March 21, 2008; accepted March 21, 2008.

Correspondence should be addressed to Dr. Toshiaki Onitsuka, Department of Neuropsychiatry, Graduate School of Medical Sciences, Kyushu University, 3-1-1, Maidashi, Higashiku, Fukuoka 812-8582, Japan. Email: toshiaki{at}npsych.med.kyushu-u.ac.jp

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help