News Releases & Research Results Elucidation of the mechanism of impaired predictability of the brain in schizophrenia

The results of collaborative research conducted by JSPS Overseas Research Fellowships Daisuke Koshiyama and Assistant Professor Kenji Kirihara and Professor Kiyoto Kasai of the Department of Neuropsychiatry, Graduate School of Medicine, the University of Tokyo Hospital.

• Patients with schizophrenia have reduced mismatch negative potentials (*1). However, whether such potentials reflect the impaired predictability of the brain (*2) or other mechanisms remain inconclusive.
  *1: Measured mainly by electroencephalography. Generally measured by an oddball task (in which subjects hear the same sound repeatedly and sometimes different sounds). Negative changes in electrical potentials that occur 100-200 milliseconds after hearing a different sound.
  *2: As recently reported, the brain processes information not passively but by predicting the surrounding environment and correcting predictions based on deviation from obtained information (prediction error) while seeing or hearing.
• In the present research, besides the routine oddball task, many standard tasks in which subjects hear multiple sounds at random were employed to measure mismatch negative potentials, demonstrating that the decrease in mismatch negative potentials in schizophrenia was caused by disorders of components associated with brain predictability.
• The results of should be applied to future research for developing therapies with animal models.

This research project was conducted with the support of the Brain Mapping by Integrated Neurotechnologies for Disease Studies by AMED.

The published online inSchizophrenia Bulletin on February 19.

Koshiyama D., et al. Reduced auditory mismatch negativity reflects impaired deviance detection in schizophreniaSchizophrenia Bulletin
DOI：10.1093/schbul/sbaa006.