Human, who has cooperative society, can tell who has reciprocity and who does not, by observing others' interaction. This study showed that highly prosocial common marmosets have this ability, but despotic Japanese monkeys do not. These results suggest that common marmoset is a suitable animal model for studying human social disorder, such as autism.

In the neonatal autism-model marmoset, we showed a significant reduction of anterior commissure, which connected bilateral social brains. Abnormal expression of axon guidance molecules mediating formation of anterior commissure were also observed in this animal-model. These features might be useful for early diagnosis and early intervention/ therapy of human autism.

The Brain/MINDS project aims to further understand the human brain and neuropsychiatric disorders through ‘‘translatable’’ biomarkers. Here, we describe the neuroethical issues of the project that have arisen from clinical data collection and the use of biological models of neuropsychiatric disorders.

Mismatch negativity (MMN) reduction is one of the most robust findings in schizophrenia that is related with early psychosis, functional abilities and translatable into animal models. We reviewed clinical MMN research and basic research in animal models and human intracranial recording for understanding neural mechanism of MMN.

We demonstrated that the gamma-band auditory steady-state response (ASSR), which is significantly impaired in patients with schizophrenia compared with healthy controls, is significantly correlated with plasma levels of D-serine, a co-agonist of the glycine binding site of N-methyl-D-aspartate (NMDA) receptor, in the schizophrenia group. These findings suggest that the gamma-band ASSR may reflect NMDA receptor function in schizophrenia.