Music rhythm perception and production relate to treatment response in schizophrenia

Accumulating evidence indicates that pathophysiology of schizophrenia involves abnormalities in the dopamine and glutamatergic neuronal systems. Antipsychotic medications are currently used to normalize dopaminergic function for schizophrenia. However, approximately 30 % of the patients have no response to antipsychotic medications, which is classified as treatment-resistant schizophrenia (TRS). Furthermore, dopamine and glutamate levels in the neural basis have been reported to differ between TRS and non-TRS. In this study, we assumed that these differences may affect music rhythm perception and production abilities between the two groups. We examined fifty-seven schizophrenia (26 TRS, 31 non-TRS) and thirty-one healthy controls (HCs) by using the Harvard Beat Assessment Test (H-BAT). As a result, we found that rhythm production was worse in patients with TRS compared to patients with non-TRS and HCs, while no difference was observed between patients with non-TRS and HCs. In addition, rhythm perception and production abilities were impaired in the whole patient group compared with HCs. Furthermore, in the patient group, the deficits were correlated with cognitive impairments. Collectively, these results suggest that patients with schizophrenia may have rhythm processing deficits, with particular a rhythm production problem in the TRS group.