Aim: The study explores IGD withdrawal-related presentations, including autonomic reaction, affective symptoms, anhedonia, and gaming urge during abstinence from gaming. We prospectively evaluated these withdrawal-related symptoms (WRS) and gaming craving during abstinence from gaming. Methods: We examined 69 individuals with IGD and 69 regular gamers and evaluated their WRS (using an exploratory questionnaire), affective and behavioral WRS (using the Questionnaire on Gaming Urge-Brief Version gaming disorder questionnaire), and heart rate. All the participants attempted to abstain from gaming before our assessment. Subsequently, some participants’ WRS and gaming craving before they engaged in gaming were prospectively evaluated. Results: In the IGD group, 85.5% experienced gaming WRS, including affective, anhedonia, and gaming urge symptoms. They could relieve these symptoms through gaming. The IGD group experienced more severe gaming WRS, gaming craving, and a higher heart rate than the regular gamer group. Gaming urge was most associated WRS of IGD. Participants with IGD experienced more severe gaming cravings when their gaming abstinence before the assessment was shorter. WRS attenuated at night and the following morning when they maintained their gaming abstinence after assessment. Conclusion: Individuals with IGD experience withdrawal-related affective, anhedonia, and gaming urge symptoms and a higher heart rate during abstinence. The WRS attenuated in 1 day. Most participants agreed that these symptoms could be relieved through gaming. Further prospective evaluation by objective assessment in an adequate sample was required to understand gaming withdrawal symptoms comprehensively.

Background: The oddball paradigm is widely applied to the investigation of cognitive function in neuroscience and in neuropsychiatry. Whether cortical oscillation in the resting state can predict the elicited oddball event-related potential (ERP) is still not clear. This study explored the relationship between resting electroencephalography (EEG) and oddball ERPs. The regional powers of 18 electrodes across delta, theta, alpha and beta frequencies were correlated with the amplitude and latency of N1, P2, N2 and P3 components of oddball ERPs. A multivariate analysis based on partial least squares (PLS) was applied to further examine the spatial pattern revealed by multiple correlations.Results: Higher synchronization in the resting state, especially at the alpha spectrum, is associated with higher neural responsiveness and faster neural propagation, as indicated by the higher amplitude change of N1/N2 and shorter latency of P2. None of the resting quantitative EEG indices predict P3 latency and amplitude. The PLS analysis confirms that the resting cortical dynamics which explains N1/N2 amplitude and P2 latency does not show regional specificity, indicating a global property of the brain.Conclusions: This study differs from previous approaches by relating dynamics in the resting state to neural responsiveness in the activation state. Our analyses suggest that the neural characteristics carried by resting brain dynamics modulate the earlier/automatic stage of target detection.

This study aimed to estimate the incidence and relative risk of stroke and post-stroke all-cause mortality among patients with bipolar disorder. This study identified a study population from the National Health Insurance Research Database (NHIRD) between 1999 and 2003 that included 16,821 patients with bipolar disorder and 67,284 age- and sex-matched control participants without bipolar disorder. The participants who had experienced a stroke between 1999 and 2003 were excluded and were randomly selected from the NHIRD. The incidence of stroke (ICD-9-CM code 430–438) and patient survival after stroke were calculated for both groups using data from the NIHRD between 2004 and 2010. A Cox proportional-hazards model was used to compare the seven-year stroke-free survival rate and all-cause mortality rate across the two cohorts after adjusting for confounding risk factors. A total of 472 (2.81%) patients with bipolar disorder and 1,443 (2.14%) controls had strokes over seven years. Patients with bipolar disorder were 1.24 times more likely to have a stroke (95% CI = 1.12–1.38; p<0.0001) after adjusting for demographic characteristics and comorbid medical conditions. In addition, 513 (26.8%) patients who had a stroke died during the follow-up period. The all-cause mortality hazard ratio for patients with bipolar disorder was 1.28 (95% CI = 1.06–1.55; p = 0.012) after adjusting for patient, physician and hospital variables. The likelihood of developing a stroke was greater among patients with bipolar disorder than controls, and the all-cause mortality rate was higher among patients with bipolar disorder than controls during a seven-year follow-up period.

Background: The serotonin transporter gene (5-HTT) is a key regulator of serotonergic neurotransmission and has been linked to various psychiatric disorders. Among the genetic variants, polymorphisms in the5-HTTgene-linked polymorphic region (5-HTTLPR) and variable-number-of-tandem-repeat in the second intron (5-HTTVNTR) have functional consequences. However, their genetic impact on cortical oscillation remains unclear. This study examined the modulatory effects of5-HTTLPR(L-allele carriers vs. non-carriers) and5-HTTVNTR(10-repeat allele carriers vs. non-carriers) polymorphism on regional neural activity in a young female population.Methods: Blood samples and resting state eyes-closed electroencephalography (EEG) signals were collected from 195 healthy women and stratified into 2 sets of comparisons of 2 groups each: L-allele carriers (N= 91) vs. non-carriers for5-HTTLPRand 10-repeat allele carriers (N= 25) vs. non-carriers for5-HTTVNTR. The mean power of 18 electrodes across theta, alpha, beta, gamma, gamma1, and gamma2 frequencies was analyzed. Between-group statistics were performed by an independent t-test, and global trends of regional power were quantified by non-parametric analyses.Results: Among5-HTTVNTRgenotypes, 10-repeat allele carriers showed significantly low regional power at gamma frequencies across the brain. We noticed a consistent global trend that carriers with low transcription efficiency of 5-HTT possessed low regional powers, regardless of frequency bands. The non-parametric analyses confirmed this observation, withPvalues of 3.071 × 10^-8and 1.459 × 10^-12for5-HTTLPRand5-HTTVNTR, respectively.Conclusions and Limitations: Our analyses showed that genotypes with low 5-HTT activity are associated with less local neural synchronization during relaxation. The implication with respect to genetic vulnerability of 5-HTT across a broad range of psychiatric disorders is discussed. Given the low frequency of 10-repeat allele of5-HTTVNTRin our research sample, the possibility of false positive findings should also be considered.

The metabolism of bioamine in the central nervous system contributes to the development of addiction. We examined the roles of hostility and depression in the association between internet gaming disorder (IGD) and monoamine oxidase-A (MAOA) EcoRV polymorphism (rs1137070). A total of 69 adults with IGD and 138 without IGD were recruited through diagnostic interviewing. We evaluated participants for rs1137070, depression, and hostility. The participants with the TT genotype of rs1137070 had a higher odds ratio of 2.52 (1.37–4.64) for IGD compared with the C carriers. Expressive hostility behavior and hostility cognition mediated the association between rs1137070 and IGD. Indicating lower MAOA activity, the TT genotype predicted IGD and higher expressive hostility behavior and hostility cognition. Expressive hostility behavior and hostility cognition may underline the association between rs1137070 and IGD. Assessment of and intervention for hostility behavior and cognition should be provided to attenuate the risk of IGD, particularly in those with the TT genotype. Further brain imaging or neurobiological studies are required to elucidate the possible mechanism underlying the association between MAOA activity and IGD.