VIP interneurons in sensory cortex encode sensory and action signals but not direct reward signals.

Vasoactive intestinal peptide (VIP) interneurons in sensory cortex modulate sensory responses based on global exploratory behavior and arousal state, but their function during non-exploratory, goal-directed behavior is not well understood. In particular, whether VIP cells are activated by sensory cues, reward-seeking actions, or directly by reinforcement is unclear. We trained mice on a Go/NoGo whisker touch detection task that included a delay period and other features designed to separate sensory-evoked, action-related, and reward-related neural activity. Mice had to lick in response to a whisker stimulus to receive a variable-sized reward. Using two-photon calcium imaging, we measured ΔF/F responses of L2/3 VIP neurons in whisker somatosensory cortex (S1) during behavior. In both expert and novice mice, VIP cells were strongly activated by whisker stimuli and goal-directed actions (licking), but not by reinforcement. VIP cells showed somatotopic whisker tuning that was spatially organized relative to anatomical columns in S1, unlike lick-related signals which were spatially widespread. In expert mice, lick-related VIP responses were suppressed, not enhanced, when a reward was delivered, and the amount of suppression increased with reward size. This reward-related suppression was not seen in novice mice, where reward delivery was not yoked to licking. These results indicate that besides arousal and global state variables, VIP cells are activated by local sensory features and goal-directed actions, but not directly by reinforcement. Instead, our results are consistent with a role for VIP cells in encoding the expectation of reward associated with motor actions.

Suicide and the standardized mortality ratio among Republic of Korea Armed Forces personnel, 2011-2016.

PURPOSE: This study examined the number of suicides in the Republic of Korea (ROK) Armed Forces and compared the relative suicide risk of military personnel with that in the general population. METHODS: Age-, sex-, and calendar year-adjusted standardized mortality ratios (SMRs) and 95% confidence intervals were calculated to compare the number of suicides between the ROK Armed Forces and the general population. RESULTS: Between 2011 and 2016, there were 405 suicides by ROK Armed Forces Personnel. The ROK Armed Forces had significantly fewer suicides than expected compared with the general population (SMR = 0.46, 95% confidence interval 0.41~0.50, based on 405 deaths). This was evident for both rank groups (soldiers and officers). In addition, a significant decrease was observed in the soldier group when comparing the SMR in 2016 with the previous 5-year average. CONCLUSIONS: Overall, during the period 2011-2016, the ROK Armed Forces had fewer suicides than expected when compared with the general population.

The effect of repeated exposure to virtual gambling cues on the urge to gamble.

INTRODUCTION: This study aimed to investigate the effectiveness of using a virtual reality (VR) casino environment in cue exposure therapy (CET) for gambling. The main objective of this study was to assess the ability of five VR casino cues to elicit subjective reactions and physiological responses that can be used within the CET paradigm. A second objective was to analyze changes in participants' urge to gamble after repeated exposure to a VR casino program and relaxation training. METHODS: Twelve recreational gamblers were exposed to five virtual environments with casino-related cues that reproduced typical gambling situations. Self-reported subjective urges and psychophysiological responses were recorded during exposure. RESULTS: All virtual environments with casino-related cues generated craving in recreational gamblers, whereas no increase in the psychophysiological variables was observed. In addition, urges to gamble elicited by VR casino environment reduced through repeated exposure and relaxation training. CONCLUSION: These findings provide evidence of the effectiveness of VR for simulating casino environments in the treatment of gambling.

Comparison of the effectiveness of virtual cue exposure therapy and cognitive behavioral therapy for nicotine dependence.

Previous studies have reported promising results regarding the effect of repeated virtual cue exposure therapy on nicotine dependence. This study aimed to compare the effectiveness of virtual cue exposure therapy (CET) and cognitive behavioral therapy (CBT) for nicotine dependence. Thirty subjects with nicotine dependence participated in 4 weeks of treatment with either virtual CET (n=15) or CBT (n=15). All patients were male, and none received nicotine replacement treatment during the study period. The main setting of the CET used in this study was a virtual bar. The primary foci of the CBT offered were (a) smoking cessation education, (b) withdrawal symptoms, (c) coping with high-risk situations, (d) cognitive reconstruction, and (e) stress management. Daily smoking count, level of expiratory carbon monoxide (CO), level of nicotine dependence, withdrawal symptoms, and subjective craving were examined on three occasions: week 0 (baseline), week 4 (end of treatment), and week 12 (follow-up assessment). After treatment, the daily smoking count, the expiratory CO, and nicotine dependence levels had significantly decreased. These effects continued during the entire study period. Similar changes were observed in both virtual CET and CBT groups. We found no interaction between type of therapy and time of measurement. Although the current findings are preliminary, the present study provided evidence that virtual CET is effective for the treatment of nicotine dependence at a level comparable to CBT.

Dysfunctional inhibitory control and impulsivity in Internet addiction.

The purpose of this study was to explore a psychological profile of Internet addiction (IA) considering impulsivity as a key personality trait and as a key component of neuropsychological functioning. Twenty three subjects with IA (Young's Internet Addiction Test scores=70 or more) and 24 sex-, age-, and intelligence-matched healthy controls were enrolled. Participants filled out a questionnaire about trait impulsivity, the Trait Characteristic Inventory, depression, and anxiety. Next, we administered traditional neuropsychological tests including the Stroop et al. and computerized neuropsychological tests using the Cambridge Neuropsychological Test Automated Battery. The IA group exhibited more trait impulsivity than the healthy control group. They also scored higher for novelty seeking and harm avoidance. The IA group performed more poorly than the healthy control group in a computerized stop signal test, a test for inhibitory function and impulsivity; no group differences appeared for other neuropsychological tests. The IA group also scored higher for depression and anxiety, and lower for self-directedness and cooperativeness. In conclusion, individuals with IA exhibited impulsivity as a core personality trait and in their neuropsychological functioning.