Effect of high-definition transcranial direct current stimulation on improving depression and modulating functional activity in emotion-related cortical-subcortical regions in bipolar depression

Functional connectivity alterations in the thalamus among patients with bronchial asthma

Objective

Bronchial Asthma (BA) is a common chronic respiratory disease worldwide. Earlier research has demonstrated abnormal functional connectivity (FC) in multiple cognition-related cortices in asthma patients. The thalamus (Thal) serves as a relay center for transmitting sensory signals, yet the modifications in the thalamic FC among individuals with asthma remain uncertain. This research employed the resting-state functional connectivity (rsFC) approach to explore alterations in thalamic functional connectivity among individuals with BA.

Patients and methods

After excluding participants who did not meet the criteria, this study finally included 31 patients with BA, with a gender distribution of 16 males and 15 females. Subsequently, we recruited 31 healthy control participants (HC) matched for age, gender, and educational background. All participants underwent the Montreal Cognitive Assessment (MoCA) and the Hamilton Depression Rating Scale (HAMD) assessment. Following this, both groups underwent head magnetic resonance imaging scans, and resting-state functional magnetic resonance imaging (rs-fMRI) data was collected. Based on the AAL (Automated Anatomical Labeling) template, the bilateral thalamic regions were used as seed points (ROI) for subsequent rsFC research. Pearson correlation analysis was used to explore the relationship between thalamic functional connectivity and neuropsychological scales in both groups. After controlling for potential confounding factors such as age, gender, intelligence, and emotional level, a two-sample t-test was further used to explore differences in thalamic functional connectivity between the two groups of participants.

Result

Compared to the HC group, the BA group demonstrated heightened functional connectivity (FC) between the left thalamus and the left cerebellar posterior lobe (CPL), left postcentral gyrus (PCG), and right superior frontal gyrus (SFG). Concurrently, there was a decrease in FC with both the Lentiform Nucleus (LN) and the left corpus callosum (CC). Performing FC analysis with the right thalamus as the Region of Interest (ROI) revealed an increase in FC between the right thalamus and the right SFG as well as the left CPL. Conversely, a decrease in FC was observed between the right thalamus and the right LN as well as the left CC.

Conclusion

In our study, we have verified the presence of aberrant FC patterns in the thalamus of BA patients. When compared to HCs, BA patients exhibit aberrant alterations in FC between the thalamus and various brain areas connected to vision, hearing, emotional regulation, cognitive control, somatic sensations, and wakefulness. This provides further confirmation of the substantial role played by the thalamus in the advancement of BA.

Safety and Efficacy of an Intensified and Repeated Transcranial Direct Current Stimulation Targeting Supplementary Motor Area and Dorsolateral Prefrontal Cortex in Trichotillomania (Hair Pulling Disorder): A Case Report

Trichotillomania (or hair pulling disorder) is a habitual condition in which patients constantly pull their hair. Although psychotherapies such as behavioral therapy and pharmacotherapy have shown relative effectiveness for trichotillomania, some patients fail to respond to these interventions or show only partial responses. Recently, noninvasive brain stimulation techniques such as transcranial direct current stimulation have shown promise in the treatment of psychiatric disorders. We designed a new protocol that included intensified and repeated during 16 sessions, every other day, 2 sessions one day, current intensity of 2 mA for 20 minutes, which regions dorsolateral prefrontal cortex (DLPFC) and supplementary motor area (SMA): Anodal (F3) and cathodal (SMA) were selected as stimulation target areas. The results showed that after the electrical stimulation intervention and also in the follow-up phase, there was a significant improvement in hair pulling behavior and psychiatric evaluations such as depression and anxiety. Therefore, there are many hopes in the effectiveness of the protocol used (intensified and repeated DLPFC and SMA areas) in the treatment of trichotillomania disorder, although there is a need for a future experimental study with a larger group of patients.

"Amity Seizures": A previously unreported semiology localizing to a circuit between the right hippocampus and orbitofrontal area

We describe a case of focal epilepsy with a semiology consisting of behaviors indicating an enthusiastic desire for those around him to get along and engage in friendly relations, which we refer to as "amity seizures". The patient was a 41-year-old right-handed male with seizures since age 26. Semiology consisted of stereotyped enthusiastic behaviors such as expressing "Peace! Peace!… Come on, we all on the same team, right?!", and giving hugs, kisses, and high-fives to those around him. On SEEG evaluation, 2 independent areas of seizure onset were identified, the right hippocampus and right posterior orbitofrontal area. Locally confined seizures had bland manifestation. However, spread from right hippocampus to right orbitofrontal area, or vice versa, elicited his typical amity seizure semiology. To our knowledge this is the first report of the seizure semiology we have coined "Amity seizures". While emotions were once thought to localize to discrete brain regions, they are now accepted to arise from networks across multiple brain regions. The fact that this behavior only occurred when seizures spread from either of 2 onset zones to the other suggests that this semiology results from network engagement between, and likely beyond, either onset zone.

Comparing different non-invasive brain stimulation interventions for bipolar depression treatment: A network meta-analysis of randomized controlled trials

Non-invasive brain stimulation (NIBS) is a promising treatment for bipolar depression. We systematically searched for randomized controlled trials on NIBS for treating bipolar depression (INPLASY No: 202340019). Eighteen articles (N = 617) were eligible for network meta-analysis. Effect sizes were reported as standardized mean differences (SMDs) or odds ratios (ORs) with 95% confidence intervals (CIs). Anodal transcranial direct current stimulation over F3 plus cathodal transcranial direct current stimulation over F4 (a-tDCS-F3 +c-tDCS-F4; SMD = -1.18, 95%CIs = -1.66 to -0.69, N = 77), high-definition tDCS over F3 (HD-tDCS-F3; -1.17, -2.00 to -0.35, 25), high frequency deep transcranial magnetic stimulation (HF-dTMS; -0.81, -1.62 to -0.001, 25), and high frequency repetitive TMS over F3 plus low frequency repetitive TMS over F4 (HF-rTMS-F3 +LF-rTMS-F4; -0.77, -1.43 to -0.11, 38) significantly improved depressive symptoms compared to sham controls. Only a-tDCS-F3 +c-tDCS-F4 (OR = 4.53, 95%CIs = 1.51-13.65) and HF-rTMS-F3 +LF-rTMS-F4 (4.69, 1.02-21.56) showed higher response rates. No active NIBS interventions exhibited significant differences in dropout or side effect rates, compared with sham controls.