Transcranial direct current stimulation (tDCS), a noninvasive brain stimulation technique, has shown some promise as a novel treatment approach for a range of mental health disorders, including OCD. This study provides a systematic review of the literature involving randomized controlled trials of tDCS for OCD and evaluates the quality of reporting using the CONSORT (Consolidating Standards of Reporting Trials) statement. This study also examined the outcomes of tDCS as a therapeutic tool for OCD.

This systematic review was prospectively registered with PROSPERO (CRD42023426005) and the data collected in accordance with the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. The quality of reporting of included studies was evaluated in accordance with the CONSORT statement.

Eleven randomized controlled trials were identified. Evaluation of the reviewed studies revealed low levels of overall compliance with the CONSORT statement highlighting the need for improved reporting. Key areas included insufficient information about - the intervention (for replicability), participant flow, recruitment, and treatment effect sizes. Study discussions did not fully consider limitations and generalizability, and the discussion/interpretation of the findings were often incongruent with the results and therefore misleading. Only two studies reported a significant difference between sham and active tDCS for OCD outcomes, with small effect sizes noted.

The variability in protocols, lack of consistency in procedures, combined with limited significant findings, makes it difficult to draw any meaningful conclusions about the effectiveness of tDCS for OCD. Future studies need to be appropriately powered, empirically driven, randomized sham-controlled clinical trials.

Traumatic Brain Injury (TBI) often leads to cognitive impairments, particularly regarding working memory (WM). This meta-analysis aims to examine the impact of TBI on WM, taking into account moderating factors which has received little attention in previous research, such as severity of injury, the different domains of Baddeley’s multi-component model, and the interaction between these two factors, as well as the interaction with other domains of executive functions.

Following Preferred Reporting Items for Systematic Reviews and Meta-analyses guidelines, a systematic review and meta-analysis searched Google Scholar, PubMed, and PsycNET for studies with objective WM measures. Multiple meta-analyses were performed to compare the effects of TBI severity on different WM components. Twenty-four English, peer-reviewed articles, mostly cross-sectional were included.

TBI significantly impairs general WM and all Baddeley’s model components, most notably the Central Executive (d’ = 0.74). Severity categories, mild-moderate and moderate-severe, were identified. Impairment was found across severities, with “moderate-severe” demonstrating the largest effect size (d’ = 0.81). Individuals with moderate-severe TBI showed greater impairments in the Central Executive and Episodic Buffer compared to those with mild-moderate injury, whereas no such differences were found for the Phonological Loop and Visuospatial Sketchpad.

These findings enhance our understanding of WM deficits in varying severities of TBI, highlighting the importance of assessing and treating WM in clinical practice and intervention planning.

High-definition transcranial direct current stimulation (HD-tDCS) has the potential to improve cognitive functioning following neurological injury and in neurodegenerative conditions. In this case report, we present the first use of HD-tDCS in a person with severe anterograde amnesia following carbon monoxide poisoning.

The participant underwent two rounds of HD-tDCS that were separated by 3 months (Round 1 = 30 sessions; Round 2 = 31 sessions). We used finite element modeling of the participant’s structural MRI to develop an individualized montage that targeted multiple brain regions involved in memory encoding, as identified by Neurosynth.

Overall, the participant’s objective cognitive functioning improved significantly following Round 1, declined during the 2 months without HD-tDCS, and again improved following Round 2. Subjective informant reports from family and medical personnel followed this same pattern of improvement following each round with a decline in between rounds. We also provide preliminary evidence of altered brain activity during a learning/memory task using functional near-infrared spectroscopy, which may help establish the physiological effects of HD-tDCS in future work.

Overall, these findings reinforce the potential value of HD-tDCS as a user-friendly method of enhancing cognition following anoxic/hypoxic brain injury.