Neuroreport
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Changes in the visual environment might be detected automatically. This function is provided by the sensory systems and showed, for instance, by the pop-out phenomenon. ⋯ In this study, the deviating stimulus feature was embedded in a task-relevant object presented in the focus of attention. With this, visual mismatch negativity was observable only with position deviants presented in the upper visual half field but not by lower half field presentation or color deviants.
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Early studies of rest cerebral metabolism and perfusion reported no association with intellectual capacity. We revisit this issue using a larger sample (N=146) and a continuous arterial spin labeling technique to measure perfusion, and working memory capacity as a measure of intellectual capacity. ⋯ However, there were also weak positive correlations in the auditory areas, accompanied by analogous correlations in all other areas associated with sensory modalities, with a preference for right lateralization. These findings are discussed in terms of the cortical and vascular organization of the brain.
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We established a human embryonic stem cell line derived from frozen human embryos of Chinese origin. The cell line expressed the pluripotent markers SSEA-4, TRA-1-60, TRA-1-81, Oct-4, and alkaline phosphatase. The pluripotency of the cell line was also demonstrated in vivo by teratoma formation in severe combined immunodeficiency mice. ⋯ The embryoid bodies were transferred to an adherent culture system in serum-free medium. The differentiating cells derived from the embryoid bodies expressed Nestin and Sox2, markers of neural progenitor cells. After the induction of cyclic AMP for 7 days, the neural progenitor cells had differentiated into neurons and glial cells.
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Feedback negativity (FN) is elicited when the outcome is worse than expected. Here we report that changes in outcome probabilities affect the reward prediction level reflected in the FN. We used a slot machine-like gambling task in which a button press produced one of the six outcomes: -10, -5, -1, +1, +5, and +10. ⋯ The smaller gains elicited an FN when the largest gain occurred frequently, whereas the smaller losses continued eliciting an FN even when the largest loss occurred frequently. The reward prediction level appears to be easy to raise but difficult to diminish. This disposition helps overcome a suboptimal situation.
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The primary mechanism by which cocaine induces stereotypy has been difficult to discern because cocaine has three high-affinity targets: the reuptake transporters for dopamine (DAT), norepinephrine, and serotonin. To dissect out the role of DAT in cocaine effects, we generated a knock-in mouse line with a cocaine-insensitive DAT (DAT-CI mice). DAT-CI mice provide a powerful tool that can directly test whether DAT inhibition is important for cocaine-induced stereotypy. ⋯ In fact, 40 mg/kg cocaine suppressed stereotypy in DAT-CI mice but produced profound stereotypy in wild-type mice. These findings suggest that DAT inhibition is necessary for cocaine-induced stereotypy. Furthermore, mechanisms independent of DAT inhibition appear to inhibit stereotypy.