Computational neuroimaging study finds tDCS anxiety reduction linked to specific fMRI connectivity patterns in older adults

This primary study abstract investigates the relationship between transcranial direct-current stimulation (tDCS) response and anxiety reduction in older adults at risk for Alzheimer's disease. The intervention involved tDCS combined with resting-state functional magnetic resonance imaging (fMRI). The authors utilized a BETA pipeline to analyze neural circuitry coupling and functional connectivity subtypes within this specific population.

Four distinct subtypes were identified through this computational approach. Two clusters demonstrated significant anxiety reduction following stimulation, while one cluster was resistant to frontal-lobe tDCS. Responsive subtypes were defined by strengthened connectivity between the lateral occipital cortex-superior division (sLOC) and medial frontal cortex (MedFC), as well as between sLOC and intracalcarine cortex (ICC). These patterns suggest specific neural mechanisms may predict treatment response.

The evidence has notable limitations. The publication type is an abstract, and specific metrics such as sample size, follow-up duration, p-values, and confidence intervals were not reported. The authors explicitly note that causality is not established, describing only an association between fMRI-based subtyping and tDCS response. Additionally, tDCS efficacy is not universal, as only two of four subtypes demonstrated significant anxiety reduction.

Despite these constraints, the findings provide a concrete roadmap for precision psychiatry in Alzheimer's disease and related dementias. The authors suggest this supports facilitating tailored therapeutic strategies for anxiety. Clinicians should interpret these results cautiously given the lack of statistical reporting and the preliminary nature of the abstract. Safety data regarding adverse events and tolerability were also not reported.