Neural Noise- A randomized controlled trial evaluated targeted high-definition tDCS over the left DLPFC to modify cognitive biases in young adults with social anxiety (Molecular Psychiatry).1
- Fits transcranial stimulation and neuromodulation focus.1
- 74 university students with elevated social anxiety (LSAS score ≥ 55) were randomized to active HD-tDCS (n=37) or sham (n=37); each received ten 20-minute sessions of offline anodal HD-tDCS over the left DLPFC across five consecutive days (two sessions per day, 3-hour interval).1
- Three cognitive bias domains were assessed with behavioral tasks pre- and post-intervention and at 1-month follow-up: attention bias, interpretation bias, and memory bias.1
- Mixed-model MANOVA showed HD-tDCS significantly improved all three behavioral bias measures simultaneously: F(3,43) = 3.97, η² = 0.22, p = 0.014, indicating a medium-to-large effect size across attention avoidance, negative interpretation bias, and negative memory bias.1
- Critically, linear mixed-effects modeling found no significant difference between groups on self-reported social anxiety symptoms, suggesting HD-tDCS altered underlying cognitive processing mechanisms without directly changing conscious symptom experience at this stage.1
- The theoretical framing is that left DLPFC hyperactivation enhances top-down cognitive control over the amygdala, suppressing threat-related attentional capture — a mechanism supported by prior single-session tDCS-SAD work (Heeren et al., 2017) and consistent with broader DLPFC-as-transdiagnostic-target literature.2
- HD-tDCS vs. conventional tDCS: High-definition montages (small focal electrodes vs. large pad electrodes) provide more spatially precise current delivery, enabling more targeted left DLPFC modulation with reduced current spread to adjacent regions — this is the first RCT to apply offline HD-tDCS to the social anxiety cognitive bias domain.1
- Authors are from Liaoning Normal University, South China Normal University (Key Laboratory of Brain, Cognition and Education Sciences, MoE), De Montfort University (UK), and Nanjing University; funding from the National Natural Science Foundation of China.1
- The dissociation between behavioral bias improvement and unchanged self-reported symptoms highlights a known challenge in neuromodulation-based CBT augmentation: cognitive process changes may precede or be necessary but not sufficient for symptom-level change, motivating combined HD-tDCS + psychological intervention paradigms.2