# Multi-Focal Symptom-Based Neuromodulation for Memory and Depression in Dementia

## TL;DR

This study shows that a home-based brain stimulation treatment combining tACS and tDCS is safe and well-tolerated for treating depression and memory issues in dementia patients.

## Contribution

The study introduces a combined tACS + tDCS intervention administered at home by caregivers for MDD+D.

## Key findings

- All ten participants completed the 4-week home-based tACS + tDCS intervention with high adherence.
- Scalp sensations were the most common side effect, mostly mild, with 90% of participants willing to repeat the treatment.
- The intervention was found to be feasible, safe, and well-tolerated, supporting further research.

## Abstract

Major depressive disorder in the context of dementia (MDD + D) is highly prevalent, on the rise, and a leading cause of impairment in older adults. It accelerates functional decline, worsens health outcomes, hastens long-term care admission, increases caregiver burden, and raises mortality risk. MDD+D involves brain network dysfunction affecting mood and memory. Transcranial direct current stimulation (tDCS) improves mood in MDD, while transcranial alternating current stimulation (tACS) enhances memory in dementia. Combining these neuromodulation techniques offers a promising dual-targeted intervention. This study evaluates the safety and feasibility of a home-based, caregiver-administered tACS + tDCS intervention. Ten participants (8 female, average age 73 ± 7.13) underwent a 4-week intervention consisting of 20-minute sessions, five days per week, targeting the left prefrontal cortex (tDCS) and left angular gyrus (tACS). Caregivers, trained by study staff, administered the stimulation with initial tele-supervision before continuing independently with remote monitoring. Participants completed questionnaires to assess safety and feasibility. Following the intervention, participants assessed their experience. All ten participants completed the study, with eight adhering to 100% of sessions, one completing 95%, and one 90%. Across 197 total sessions, the most reported side effect was scalp sensations (tingling, itching), mild in 55%, moderate in 21%, and severe in 1%. 90% of participants expressed willingness to repeat the program and continue for a longer duration. A home-based tACS + tDCS program is feasible, safe, and well-tolerated, with high adherence and satisfaction, supporting further investigation into at-home tACS + tDCS treatment for MDD+D.