Alterations in the brain functional network of abstinent male individuals with methamphetamine use disorder.

Methamphetamine is a highly addictive psychostimulant drug that is abused globally and is a serious threat to health worldwide. Unfortunately, the specific mechanism underlying addiction remains unclear. Thus, this study aimed to investigate the characteristics of functional connectivity in the brain network and the factors influencing methamphetamine use disorder in patients using magnetic resonance imaging. We included 96 abstinent male participants with methamphetamine use disorder and 46 age- and sex-matched healthy controls for magnetic resonance imaging. Compared with healthy controls, participants with methamphetamine use disorder had greater impulsivity, fewer small-world attributes of the resting-state network, more nodal topological attributes in the cerebellum, greater functional connectivity strength within the cerebellum and between the cerebellum and brain, and decreased frontoparietal functional connectivity strength. In addition, after controlling for covariates, the partial correlation analysis showed that small-world properties were significantly associated with methamphetamine use frequency, psychological craving, and impulsivity. Furthermore, we revealed that the small-word attribute significantly mediated the effect of methamphetamine use frequency on motor impulsivity in the methamphetamine use disorder group. These findings may further improve our understanding of the neural mechanism of impulse control dysfunction underlying methamphetamine addiction and assist in exploring the neuropathological mechanism underlying methamphetamine use disorder-related dysfunction and rehabilitation.

Functional connectivity of the left inferior parietal lobule mediates the impact of anxiety and depression symptoms on sleep quality in healthy adults.

Individuals with anxiety and depression symptoms are vulnerable to sleep disturbances. The current study aimed to explore the shared neuro-mechanisms underlying the effect of anxiety and depression symptoms on sleep quality. We recruited a cohort of 92 healthy adults who underwent functional magnetic resonance imaging scanning. We measured anxiety and depression symptoms using the Zung Self-rating Anxiety/Depression Scales and sleep quality using the Pittsburgh Sleep Quality Index. Independent component analysis was used to explore the functional connectivity (FC) of brain networks. Whole-brain linear regression analysis showed that poor sleep quality was associated with increased FC in the left inferior parietal lobule (IPL) within the anterior default mode network. Next, we extracted the covariance of anxiety and depression symptoms using principal component analysis to represent participants' emotional features. Mediation analysis revealed that the intra-network FC of the left IPL mediated the association between the covariance of anxiety and depression symptoms and sleep quality. To conclude, the FC of the left IPL may be a potential neural substrate in the association between the covariance of anxiety and depression symptoms and poor sleep quality, and may serve as a potential intervention target for the treatment of sleep disturbance in the future.

Problematic internet gaming and non-suicidal self-injury in Chinese adolescents: Moderating and mediating roles of anxiety.

INTRODUCTION: Despite consistent reports of the association between problematic internet gaming (PIG) and non-suicidal self-injury (NSSI), an increase in PIG does not necessarily lead to increased NSSI. This apparent paradox indicates the presence of other mediators and moderators in the PIG-NSSI association. This study aimed to investigate the role of anxiety as a potential moderating and mediating factor of the PIG-NSSI association in Chinese adolescents. METHODS: A cross-sectional study was conducted among 10,479 Chinese adolescents (50.5% male; age range, 9-18 years). Standardized self-report questionnaires were used to assess the severity of PIG, anxiety, and NSSI. Spearman correlation and multiple linear regression were applied to examine the relationships among PIG, anxiety, and NSSI. Both moderating and mediating effects of anxiety were assessed using Hayes' methods. RESULTS: PIG, anxiety symptoms, and NSSI significantly correlated with one another. Anxiety significantly moderated the relationship between PIG and NSSI [B = 0.002, standard error (SE) = 0.000, p < 0.001], and it partially mediated the PIG-NSSI association [B = 0.017, SE = 0.001, 95% confidence interval (CI) 0.014-0.021]. Social concern and concentration were the two dimensions of anxiety that exerted the strongest mediation effect (B = 0.017, SE = 0.002, 95% CI 0.014-0.020). CONCLUSIONS: Adolescents with PIG and high anxiety are likely to suffer more severe NSSI and may benefit from interventions to reduce anxiety symptoms.

Case report: Orthostatic leg tremor as the initial manifestation in a patient with metabotropic glutamate receptor-5 encephalitis without cortical dysfunction: complexities in identification and treatment.

Objective: Metabotropic glutamate receptor 5 (mGluR5) encephalitis is such a rare type of autoimmune encephalitis that its diagnosis remains a challenge. Case report: A 19-year-old female patient initially presented with anxiety and orthostatic leg tremors without cortical dysfunction. We found that this patient was positive for mGluR5 antibodies in both serum (1:1,000) and cerebrospinal fluid (1:32). After comprehensive intervention, the patient showed complete recovery at the 18-month follow-up. Discussion: This report expands our knowledge of the possible presentations of mGluR5 encephalitis for early diagnosis, which makes it possible to prevent serious consequences and improve the prognosis.

Effect of hyperbaric oxygen therapy on cognitive dysfunction induced by nitrous oxide abuse: protocol of a randomised, double-blinded, placebo-controlled trial.

INTRODUCTION: The cognitive dysfunction associated with nitrous oxide abuse is gradually becoming a major global public health concern. Despite the increasing prevalence of nitrous oxide abuse, there are currently no authorised/approved treatment options. Hyperbaric oxygen therapy (HBOT) has been proven to be an efficient method to improve cognitive function. The current randomised, double-blinded, placebo-controlled trial will explore the effect of HBOT on cognitive dysfunction induced by nitrous oxide abuse. METHODS AND ANALYSIS: Eighty participants who abuse nitrous oxide and have cognitive dysfunction, including memory decline, disorientation, attention deficits, slower reactions and learning disabilities, will be included in the trial. They will be randomly assigned to receive either HBOT or sham-HBOT 90-120 min once daily for 5 days per week for 2 weeks. The primary outcome will be the improvement in the total score of the MATRICS Consensus Cognitive Battery, which will measure comprehensive cognitive function between the two groups. Additionally, attention will be measured by integrated visual and auditory continuous performance tests, executive function will be measured by the Wisconsin card sorting test, intelligence will be measured by Raven's standard progressive matrices and cognitive control will be measured by the Stroop colour word interference test. ETHICS AND DISSEMINATION: This protocol was approved by the West China Hospital of Sichuan University Biomedical Research Ethics Committee. The report of the study will be disseminated via scientific forums including peer-reviewed publications and presentations at national and international conferences. TRIAL REGISTRATION NUMBER: Chinese Clinical Trial Registry (ChiCTR2100047111).

Characteristics of depression, anxiety, impulsivity, and aggression among various types of drug users and factors for developing severe depression: a cross-sectional study.

BACKGROUND: Mood disorder, impulsivity and aggression are common in drug users compared to healthy controls. However, no study has focused on the difference in various types of drug users. Therefore, the objective of this study was to explore the differences in depression, anxiety, impulsivity, and aggression among methamphetamine, heroin and polysubstance users and to further explore the risk factors for severe depression in the three groups. METHODS: Drug users over 18 years old who met the DSM-V diagnostic criteria for substance -related disorders were included in the study. All participants completed a general questionnaire, the Zung Self-Rating Depression Scale (SDS), the Zung Self-Rating Anxiety Scale (SAS), Barratt impulsiveness Scale Version 11 (BIS-11), and the Buss-Perry Aggression Questionnaire (BPAQ). One-way ANOVAs or Chi-square tests were used to test the differences among the groups, correlation analysis was used to test the relationship between drug use and other parameters, and multiple logistic regression was conducted to assess the risk factors for severe depression. RESULTS: A total of 1,486 participants were included, comprising 86.3% males with a mean age of 38.97 years. There was a significant difference in the percentage of severe depression and SDS scores among the three groups, but no significant difference was found in SAS, BIS-11 and BPAQ scores. Using methamphetamines, hostility and anxiety were risk factors for developing severe depression in all the participants and anxiety remained constant in the other three groups. Moreover, methamphetamine use was 2.16 and 3.35 times more likely to cause severe depression than heroin and polysubstance use, respectively. The initial age of substance use was negatively correlated with BPAQ, SAS, and SDS scores, whereas the drug use duration and addiction duration were positively correlated. CONCLUSIONS: In this study, we found that the highest prevalence of severe depression was in participants using methamphetamines and that using methamphetamines, hostility, and anxiety were risk factors for developing severe depression. This result addressed an important gap in our knowledge of the different characteristics of depression, anxiety, impulsivity and aggression in various types of substance users and provides clinicians and policy-makers with directions for intervention and preventing relapse.

Dopamine-2 receptor antibody encephalitis presenting as pure tongue-biting in a tourette syndrome patient: a case report.

BACKGROUND: Tourette syndrome (TS) is a neuropsychiatric disorder characterized by repetitive and patterned tics. Its onset correlates with dysfunctions in immunological activation and neurotransmitters. Autoimmune movement disorders such as dopamine-2 receptor antibody encephalitis (D2R encephalitis) may go undiagnosed in TS patients seeking medical help for tic symptoms only. Here, we present a clinical case of D2R encephalitis in a TS patient. CASE PRESENTATION: A 13-year-old boy with a history of TS presented with acute tongue-biting without positive neurologic examination or auxiliary examination results, except for a weakly positive finding for D2R antibodies in the serum sample. He was initially diagnosed with possible D2R encephalitis, but the influence of TS could not be ruled out. In addition to psychotropics, we administered immunotherapy early based on clinical characteristics, and his symptoms were ameliorated significantly. During the follow-up, he was diagnosed with definite D2R encephalitis, and the dosage of psychotropics was further adjusted for fluctuating symptoms. CONCLUSIONS: Our case suggests that clinicians should discern D2R encephalitis in TS patients when tics are the primary symptoms. Administering immunotherapy early, according to clinical characteristics, may benefit the patient. Moreover, the features of premonitory urges could help evaluate the state of TS.