Differential modulation of sensorimotor network between temporal interference and high-definition direct current stimulation.

Abstract

<i>Objective.</i>Temporal interference stimulation's (TISs) efficacy in modulating brain networks remains unexplored. We aimed to evaluate the differential impact of TIS and high-definition transcranial direct current stimulation (HD-tDCS) on resting-state functional connectivity (FC) and the topological properties of brain networks, particularly the sensorimotor network (SMN).<i>Approach.</i>In a randomized, double-blind, crossover study, 40 healthy adults underwent both TIS and HD-tDCS targeting the left primary motor cortex (M1). Resting-state functional magnetic resonance imaging data were collected before, during, and after stimulation. Brain networks were constructed using the Dosenbach atlas and the Yeo seven-network parcellation, with a focus on 29 regions of interests within the SMN. Network analysis included FC calculations using Pearson correlations and graph-theoretical measures of global and local efficiency. A two-way repeated measures analysis of variance was used to assess the effects of stimulation on network connectivity properties.<i>Main results.</i>(1) Both stimulation methods enhanced SMN connectivity, with TIS demonstrating greater efficacy than HD-tDCS (FC increase: 31.25% vs 22.58%). (2) TIS significantly improved SMN global and local efficiencies by 15.44% and 18.85%, respectively, while HD-tDCS increased these measures by 11.97% and 12.5%, respectively (all<i>p</i>< 0.05). (3) While both methods enhanced within-network connections of the SMN, TIS additionally strengthened the connections within the visual network, dorsal attention network (DAN), and frontoparietal network, as well as multiple between-network connections. In contrast, HD-tDCS only improved connections between SMN-DAN and SMN-default mode network.<i>Significance.</i>Both TIS and HD-tDCS enhanced SMN FC, with TIS demonstrating superior efficacy. Under specific parameter configurations, 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 compared to HD-tDCS.