Schedule of Events | Symposia

Investigation of single- and multi-electrode anodal tDCS for enhancing executive function: Implications for simplified protocols

Poster Session A - Saturday, March 29, 2025, 3:00 – 5:00 pm EDT, Back Bay Ballroom/Republic Ballroom
Also presenting in Data Blitz Session 2 - Saturday, March 29, 2025, 10:30 am – 12:00 pm EDT, Independence Ballroom.

Megan O'Connor¹ (mboconnor@mgh.harvard.edu), Asif Jamil¹, Laura Dubreuil-Vall, Joan A. Camprodon¹; ¹Massachusetts General Hospital and Harvard Medical School

While transcranial direct current stimulation (tDCS) shows promise for enhancing executive function, its outcomes vary due to differences in stimulation parameters. In motor studies, multi-site stimulation targeting broader networks proved more effective than single-site stimulation. However, it remains unclear whether a similar approach improves executive function over the traditional left dorsolateral prefrontal cortex (DLPFC) montage. In two randomized, placebo-controlled, cross-over studies, we first compared single-site versus multi-site tDCS on executive function. After finding that left DLPFC stimulation outperformed multi-site stimulation, we conducted a follow-up study to test whether this was due to differences in current intensity, modifying the multi-electrode montage to ensure both the left and right DLPFC received 2 mA each. In Study 1 (N=22), we applied 2 mA anodal tDCS targeting the left DLPFC using a standard bipolar montage vs. 2 mA anodal tDCS targeting the frontoparietal network (FPN) using a multi-electrode montage vs. sham. In Study 2 (N=22), we applied 2 mA anodal tDCS targeting the left DLPFC using a standard bipolar montage vs. 2 mA anodal tDCS targeting each the left and right DLPFC using a bilateral montage vs. sham. Subjects performed the Flanker Task before and after tDCS to assess reaction time and accuracy. In both studies, anodal tDCS targeting the left DLPFC with a standard bipolar montage significantly improved reaction time compared to both multi-electrode montages and sham. These findings suggest that a simpler, non-specific tDCS approach may be more effective than multi-site, current-intensity optimized models in improving reaction time on the Flanker Task.

Topic Area: EXECUTIVE PROCESSES: Monitoring & inhibitory control