Kazuhiko Iwata

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AIM The present study aimed to test the construct validity and internal consistency of the Social Cognition Screening Questionnaire (SCSQ) (Japanese version). METHODS We first tested whether the subscale scores and the total score of the SCSQ could discriminate patients with schizophrenia from normal controls. Next, we tested the internal consistency.(More)
We conducted a noninvasive near-infrared spectroscopy (NIRS) study using the game of rock, paper, scissors (RPS) as a simple neurocognitive task for the prefrontal cortex (PFC) in 15 healthy volunteers. We employed an opposite "to lose" RPS task coupled with a normal "to win" RPS task, since the former requires inhibition of behavior, one of the most(More)
AIMS Facial emotion perception is considered to provide a measure of social cognition. Numerous studies have examined the perception of emotion in patients with schizophrenia, and the majority has reported impaired ability to recognize facial emotion perception. We aimed to investigate the correlation between facial expression recognition and other domains(More)
AIM Methods to improve neurocognitive impairments are of important research interest. This study sought to examine the synergistic effects of neurocognitive rehabilitation and antipsychotics for schizophrenia. METHODS Subjects were 43 patients diagnosed with schizophrenia or schizoaffective disorder in a randomized trial of the effects of neurocognitive(More)
Many researchers and practitioners have suggested that improving the cognition of patients with schizophrenia is very important for achieving true "recovery". There is a strong relationship between cognitive function and social functioning; cognitive function affects functional outcomes of schizophrenic patents. Therefore, rehabilitation methods to improve(More)
Aiming to provide the synthetic speech with the ability to express speaker's intentions and subtle nuances, we investigated the relationship between the speaker's intentions that the listener perceived and sentence-final particle/intonation combinations in Japanese conversational speech. First, we classified F0 contours of sentence-final syllables in actual(More)