Abstract
The topics about emotion, decision-making and consciousness have been traditionally dealt with humanities and social sciences. However, recent advances in non- invasive neuroimaging techniques (fMRI) and cognitive sciences made these topics hot research areas in neurosciences. The emerging field of social brain research or social neuroscience will greatly contribute to clinical psychiatry. Here, I will introduce our recent interdisciplinary neuroscience approach combining molecular neuroimaging techniques (positron emission tomography : PET), cognitive sciences and economics to understand neural as well as molecular basis of altered decision- making in neuropsychiatric disorders. We found that people with low D1 receptor density in the striatum showed more non- linear probability weighting (more pronounced overestimation of low probabilities and underestimation of high probabilities). We also examined relationship between the degree of loss aversion and noradrenalin transmission by PET. Our finding was that individual with low norepinephrine transporter density in the thalamus tended to be more loss averse. We hope that understanding the molecular mechanism of extreme or impaired decision- making can contribute to the assessment and prevention of neuropsychiatric disorders.
