Temporal interference stimulation (TIS) is a promising non-invasive deep brain stimulation technique that has the potential to enhance motor function. However, potential efficacy in modulating brain networks remains largely unexplored. The present study aimed to evaluate the differential impact on brain networks of TIS and high-definition transcranial direct current stimulation (HD-tDCS) on resting-state functional connectivity (FC) and topological properties of brain networks, particularly the Sensorimotor Network (SMN). Method: In a randomized, double-blind, crossover design, 40 healthy adults received both TIS (20 Hz beat frequency, 2 mA) and HD-tDCS (2 mA) targeting the left primary motor cortex (M1). Resting-state functional magnetic resonance imaging (Rs-fMRI) data were collected pre-, during, and post-stimulation. Brain networks were constructed using the Dosenbach atlas (142 ROIs, excluding the cerebellum) and the Yeo seven-network parcellation, focusing on 29 ROIs in the SMN. Network analysis included FC calculations using Pearson correlations and graph-theoretical measures of global and local efficiency. Two-way repeated measures analysis of variance (ANOVA) evaluates the effects of stimulation on network connectivity properties. (1) Both stimulation methods enhanced SMN connectivity, with TIS showing greater efficacy than HD-tDCS (FC increase, 31.25% vs. 22.58%). (2) TIS significantly enhanced SMN global and local efficiencies by 15.44% and 18.85%, respectively; HD-tDCS increased these measures by 11.97% and 12.5%, respectively (all p < 0.05). (3) While both methods enhanced SMN within-network connections, TIS strengthened the Visual Network (VN), Dorsal Attention Network (DAN), and Frontoparietal Network (FPN) within-network connections and multiple between-network connections, whereas HD-tDCS only improved connections between SMN-DAN and SMN-Default Mode Network (DMN). Both TIS and HD-tDCS enhanced SMN functional connectivity, with the TIS demonstrating efficacy. TIS exhibited broader effects, improving both network efficiency and extensive within- and between-network connections, whereas HD-tDCS had a limited impact on the selection of network connections. These findings establish TIS as a potentially more effective neuromodulation technique for enhancing brain network properties than HD-tDCS.
Tang et al. (Thu,) studied this question.