Introduction: We measured duration mismatch negativity (dMMN), P3a, and reorienting negativity (RON) in subjects with at-risk mental state (ARMS), patients with first-episode or chronic schizophrenia, and healthy volunteers. The main interest was to determine if these event-related potentials provide a biomarker associated with progression to overt schizophrenia in ARMS subjects.
Methods: Nineteen ARMS subjects meeting the criteria of the Comprehensive Assessment of ARMS, 38 patients with schizophrenia (19 first-episode and 19 chronic), and 19 healthy controls participated in the study. dMMN, P3a, and RON were measured with an auditory odd-ball paradigm at baseline.
Results: During the follow-up period (2.2 years), 4 out of the 19 ARMS subjects transitioned to schizophrenia (Converters) while 15 did not (non-Converters). dMMN amplitudes of Converters were significantly smaller than those of non-Converters at frontal and central electrodes before onset of illness. dMMN amplitudes of non-Converters did not differ from those of healthy controls, while Converters showed significantly smaller dMMN amplitudes compared to control subjects. RON amplitudes were also reduced at frontal and central electrodes in subjects with schizophrenia, but not ARMS. Converter subjects tended to show smaller RON amplitudes compared to non-Converters.
Conclusions: Our data confirm that diminished dMMN amplitudes provide a biomarker, which is present before and after the development of psychosis. In this respect, RON amplitudes may also be useful, as suggested for the first time based on longitudinal observations.
Keywords: mismatch negativity, reorienting negativity, event-related potentials, prodromal, schizophrenia
Citation: Higuchi Y, Seo T, Miyanishi T, Kawasaki Y, Suzuki M and Sumiyoshi T (2014) Mismatch negativity and P3a/reorienting complex in subjects with schizophrenia or at-risk mental state. Front. Behav. Neurosci. 8:172. doi: 10.3389/fnbeh.2014.00172
Received: 27 January 2014; Accepted: 23 April 2014;
Published online: 13 May 2014.
Edited by:Ales Stuchlik, Academy of Sciences of the Czech Republic, Czech Republic
Reviewed by:Julio Eduardo Armijo, Universidad de Santiago, Chile
Copyright: © 2014 Higuchi, Seo, Miyanishi, Kawasaki, Suzuki and Sumiyoshi. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) or licensor are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
*Correspondence: Tomiki Sumiyoshi, Department of Clinical Research Promotion, National Center of Neurology and Psychiatry, 4-1-1 Ogawahigashi, Kodaira, Tokyo 187-8551, Japan e-mail: firstname.lastname@example.org