平野 好幸

BACKGROUND: Generalized anxiety disorder (GAD) and social anxiety disorder (SAD) are distinguished by whether anxiety is limited to social situations. However, reports on the differences in brain functional networks between GAD and SAD are few. Our objective is to understand the pathogenesis of GAD and SAD by examining the differences in resting brain function between patients with GAD and SAD and healthy controls (HCs). METHODS: This study included 21 patients with SAD, 17 patients with GAD, and 30 HCs. Participants underwent psychological assessments and resting-state functional magnetic resonance imaging (rsfMRI). Whole-brain analyses were performed to compare resting-state functional connectivity (rsFC) among the groups. Additionally, logistic regression analysis was conducted on the rsFC to identify significant differences between GAD and SAD. RESULTS: Patients with SAD and GAD had significantly higher rsFC between the bilateral postcentral gyri and bilateral amygdalae/thalami than HCs. Compared with patients with SAD, those with GAD had significantly higher rsFC between the right nucleus accumbens and bilateral thalami and between the left nucleus accumbens and right thalamus. RsFC between the left nucleus accumbens and right thalamus positively correlated with state anxiety in patients with SAD and GAD, respectively. In addition, logistic regression analysis revealed that the right nucleus accumbens and the right thalamus connectivity could distinguish SAD from GAD. CONCLUSIONS: GAD and SAD were distinguished by the right nucleus accumbens and the right thalamus connectivity. Our findings offer insights into the disease-specific neural basis of SAD and GAD.

BACKGROUND: Studies comparing the brain functions of major depressive disorder (MDD) and social anxiety disorder (SAD) at the regional and network levels remain scarce. This study aimed to elucidate their pathogenesis using neuroimaging techniques and explore biomarkers that can differentiate these disorders. METHODS: Resting-state fMRI data were collected from 48 patients with MDD, 41 patients with SAD, and 82 healthy controls. Differences in the amplitude of low-frequency fluctuations (ALFF) among the three groups were examined to identify regions showing abnormal regional spontaneous activity. A seed-based functional connectivity (FC) analysis was conducted using ALFF results as seeds and different connections were identified between regions showing abnormal local spontaneous activity and other regions. The correlation between abnormal brain function and clinical symptoms was analyzed. RESULTS: Patients with MDD and SAD exhibited similar abnormal ALFF and FC in several brain regions; notably, FC between the right superior frontal gyrus (SFG) and the right posterior supramarginal gyrus (pSMG) in patients with SAD was negatively correlated with depressive symptoms. Furthermore, patients with MDD showed higher ALFF in the right SFG than HCs and those with SAD. LIMITATION: Potential effects of medications, comorbidities, and data type could not be ignored. CONCLUSION: MDD and SAD showed common and distinct aberrant brain function patterns at the regional and network levels. At the regional level, we found that the ALFF in the right SFG was different between patients with MDD and those with SAD. At the network level, we did not find any differences between these disorders.

INTRODUCTION: Insomnia is a common health problem and cognitive-behavioural therapy (CBT) is recommended as a treatment. As there is a critical shortage of CBT-trained therapists, we developed a digital CBT application (IIIP MED: Sleepy Med) as Software as a Medical Device for insomnia. This paper describes the study protocol for an exploratory randomised controlled trial (RCT) to evaluate effectiveness and safety of our developed digital CBT (dCBT) for 5 weeks compared with zolpidem tartrate for patients with insomnia disorder. METHODS AND ANALYSIS: This proposed multicentre exploratory RCT will be conducted at the outpatient clinic of Chiba University Hospital, Akita University Hospital and Yoyogi Sleep Disorder Center, Japan. The study population comprises two parallel groups (dCBT and zolpidem) consisting of 15 participants each (n=30 in total) diagnosed with insomnia disorder who remain symptomatic at 4 weeks after sleep hygiene education. We will evaluate the effectiveness at baseline, week 5 (post-intervention) and week 10 (follow-up). The primary outcome will be the change of subjective sleep onset latency at week 5 from baseline. Secondary outcomes include sleep-related outcomes, such as objective sleep onset latency measured by mobile electroencephalography, functional improvement during the daytime and quality of life. ETHICS AND DISSEMINATION: Ethics approval was granted by the Institutional Review Board of Chiba University Hospital (K2023001). All participants will be required to provide written informed consent. Results will be published in international journals. TRIAL REGISTRATION NUMBER: jRCT2032230353.

BACKGROUND: Previous research on the changes in resting-state functional connectivity (rsFC) in anorexia nervosa (AN) has been limited by an insufficient sample size, which reduced the reliability of the results and made it difficult to set the whole brain as regions of interest (ROIs). METHODS: We analyzed functional magnetic resonance imaging data from 114 female AN patients and 135 healthy controls (HC) and obtained self-reported psychological scales, including eating disorder examination questionnaire 6.0. One hundred sixty-four cortical, subcortical, cerebellar, and network parcellation regions were considered as ROIs. We calculated the ROI-to-ROI rsFCs and performed group comparisons. RESULTS: Compared to HC, AN patients showed 12 stronger rsFCs mainly in regions containing dorsolateral prefrontal cortex (DLPFC), and 33 weaker rsFCs primarily in regions containing cerebellum, within temporal lobe, between posterior fusiform cortex and lateral part of visual network, and between anterior cingulate cortex (ACC) and thalamus (p < 0.01, false discovery rate [FDR] correction). Comparisons between AN subtypes showed that there were stronger rsFCs between right lingual gyrus and right supracalcarine cortex and between left temporal occipital fusiform cortex and medial part of visual network in the restricting type compared to the binge/purging type (p < 0.01, FDR correction). CONCLUSION: Stronger rsFCs in regions containing mainly DLPFC, and weaker rsFCs in regions containing primarily cerebellum, within temporal lobe, between posterior fusiform cortex and lateral part of visual network, and between ACC and thalamus, may represent categorical diagnostic markers discriminating AN patients from HC.