Precision Neuromodulation for Diabetes-Associated Cognitive Decline: a Transcranial Electrical Stimulation Approach

Type 3 Diabetes (T3DM), marked by brain insulin resistance, is increasingly linked to neurocognitive decline and Alzheimer's pathogenesis, necessitating novel non-pharmacological interventions. This study investigated anodal transcranial direct current stimulation (tDCS) targeting the left DLPFC (F3 region) to improve cognitive deficits in insulin-dependent diabetic patients with diabetes-associated cognitive decline (DACD).

This study utilized a randomized, double-blind, two-group clinical trial design. Diabetic patients aged 60-80 years in Tehran and Bonab experiencing brain fog and cognitive decline constituted the target population. Recruitment and execution occurred from autumn 2024 to spring 2025. A purposive sampling method selected 23 matched participants per group, adhering to strict inclusion/exclusion criteria. Participants were then randomly assigned to either the experimental or control group. The experimental group received 30 tDCS sessions. Cognitive status and memory were assessed using the mini-mental state examination as the primary outcome and the prospective and retrospective memory questionnaire as a supplementary measure. Repeated Measures ANOVA analyzed the data.

The results indicated that tDCS administered to the DLPFC in the experimental cohort significantly enhanced overall cognitive function and reduced subjective memory complaints (p < .01). Additionally, a statistically significant reduction in glycated hemoglobin was observed across nearly all participants in the experimental group (p < .01).

These findings indicate that tDCS presents a promising, non-invasive therapeutic approach. It demonstrates potential for enhancing cognitive function in patients with DACD and for facilitating improved long-term glycemic control. This highlights the role of brain neuromodulation as a component in the management of diabetes-related complications.