Serotonin Differentially Regulates Short- and Long-Term Prediction of Rewards in the Ventral and Dorsal Striatum

BACKGROUND: The ability to select an action by considering both delays and amount of reward outcome is critical for maximizing long-term benefits. Although previous animal experiments on impulsivity have suggested a role of serotonin in behaviors requiring prediction of delayed rewards, the underlying neural mechanism is unclear. METHODOLOGY/PRINCIPAL FINDINGS: To elucidate the role of serotonin in the evaluation of delayed rewards, we performed a functional brain imaging experiment in which subjects chose small-immediate or large-delayed liquid rewards under dietary regulation of tryptophan, a precursor of serotonin. A model-based analysis revealed that the activity of the ventral part of the striatum was correlated with reward prediction at shorter time scales, and this correlated activity was stronger at low serotonin levels. By contrast, the activity of the dorsal part of the striatum was correlated with reward prediction at longer time scales, and this correlated activity was stronger at high serotonin levels. CONCLUSIONS/SIGNIFICANCE: Our results suggest that serotonin controls the time scale of reward prediction by differentially regulating activities within the striatum

Development of a gamma-ray tracking detector and its performance test

The gamma-ray tracking detector is a germanium detector realizing both high efficiency and Compton background suppression by reconstructing the scattering process of the incident gamma-rays from the positions and energy deposits of the gamma-rays at each interaction points in the detector. Its high position resolution is also beneficial for accurate Doppler correction. In the tracking detector, the interaction positions are determined three-dimensionally with high position resolution by analyzing the signal waveform from the segmented electrodes. We have measured waveforms for different interaction points of gamma-rays using a GRETINA Quad Detector. The experiment was performed using a gamma-ray beam from the GACKO beam line at the NewSUBARU electron storage ring facility. The three dimensional position of the interaction in points are selected first by collimating the incident gamma-rays and then by measuring the gamma-rays scatted at 90 degree in the detector by using a narrow slit. Obtained waveforms were compared with the simulated waveform.5th Joint Meeting of the APS Division of Nuclear Physics and the Physical Society of Japa

Active life expectancy for people over 65 years old in a local city in the northern part of Tohoku district

Life expectancy does not necessarily match quality of life (QOL). A cohort study involving a population of 10,107 in a certain city of Japan was conducted to evaluate active life expectancy (ALE), which has a direct relationship with QOL. The ALE that took functional recovery rates into account was 17.20 and 19.08 years for males and females respectively, at the age of 65. These values increased by 2.98 and 3.87 years for men and women, respectively, compared with when functional recovery rates were not considered. ALE may serve as an indicator for the objective evaluation of various public health services provided by local governments

National trends in the outcomes of subarachnoid haemorrhage and the prognostic influence of stroke centre capability in Japan: retrospective cohort study

Objectives To examine the national, 6-year trends in in-hospital clinical outcomes of patients with subarachnoid haemorrhage (SAH) who underwent clipping or coiling and the prognostic influence of temporal trends in the Comprehensive Stroke Center (CSC) capabilities on patient outcomes in Japan.Design Retrospective study.Setting Six hundred and thirty-one primary care institutions in Japan.Participants Forty-five thousand and eleven patients with SAH who were urgently hospitalised, identified using the J-ASPECT Diagnosis Procedure Combination database.Primary and secondary outcome measures Annual number of patients with SAH who remained untreated, or who received clipping or coiling, in-hospital mortality and poor functional outcomes (modified Rankin Scale: 3–6) at discharge. Each CSC was assessed using a validated scoring system (CSC score: 1–25 points).Results In the overall cohort, in-hospital mortality decreased (year for trend, OR (95% CI): 0.97 (0.96 to 0.99)), while the proportion of poor functional outcomes remained unchanged (1.00 (0.98 to 1.02)). The proportion of patients who underwent clipping gradually decreased from 46.6% to 38.5%, while that of those who received coiling and those left untreated gradually increased from 16.9% to 22.6% and 35.4% to 38%, respectively. In-hospital mortality of coiled (0.94 (0.89 to 0.98)) and untreated (0.93 (0.90 to 0.96)) patients decreased, whereas that of clipped patients remained stable. CSC score improvement was associated with increased use of coiling (per 1-point increase, 1.14 (1.08 to 1.20)) but not with short-term patient outcomes regardless of treatment modality.Conclusions The 6-year trends indicated lower in-hospital mortality for patients with SAH (attributable to better outcomes), increased use of coiling and multidisciplinary care for untreated patients. Further increasing CSC capabilities may improve overall outcomes, mainly by increasing the use of coiling. Additional studies are necessary to determine the effect of confounders such as aneurysm complexity on outcomes of clipped patients in the modern endovascular era