Investigating the Efficacy and Mechanisms of Individualized tACS Targeting Anhedonia in Late-Life Depression

Conditions studied

Late-Life Depression, Anhedonia

About this study

This project focuses on clinical translational research into personalized transcranial alternating current stimulation (tACS) for treating anhedonia in late-life depression (LLD). Key components include: (1) Optimizing individualized tACS treatment parameters through randomized, double-blind, controlled trials and establishing precise treatment protocols using deep learning algorithms; (2) Assessing the short-term (2 weeks) and long-term (3 months) efficacy of tACS on depressive symptoms and anhedonia using scales such as the HAMD, SHAPS, and DARS, while monitoring safety; (3) Integrating multimodal detection technologies (64-channel EEG, inflammatory factors/neurotransmitters, etc.) to elucidate the mechanisms by which tACS alleviates anhedonia through modulating prefrontal neural oscillations (y-band), improving synaptic plasticity (increased BDNF), and regulating neurotransmitters (5-HT, DA). This study will establish, for the first time, an individualized parameter system for tACS treatment of LLD, providing a novel non-pharmacological intervention strategy for clinical practice.

Interventions

• Device: Transcranial Alternating Current Stimulation (tACS) — divided into a real-stimulus group and a sham-stimulus group
• Device: shame tACS — The sham tACS group received 40 Hz tACS with a peak-to-peak amplitude of 1 mA, a frequency of y, and a sinusoidal waveform. The stimulation sites were located in the prefrontal cortex (F3 and F4) based on the 10-20 system of international EEG electrode placement, with CZ serving as the return electrode, which did not generate stimulation pulses.

Primary outcomes

• Dimensional Anhedonia Rating Scale (DARS) (12 week)