Exploring the Mechanisms of Temporal Interference Stimulation in Enhancing Spatial Working Memory Performance through Frontoparietal Modulation

Temporal Interference Stimulation (TIS) has garnered attention for cognitive modulation; however, its mechanisms remain debated. This study introduces a novel protocol of theta-band TIS on spatial working memory (SWM) by targeting two regions (IPL, MFG) simultaneously, utilizing a change detection paradigm and fMRI to assess behavioral and neural changes. Behavioral results demonstrate TIS’s capacity to significantly enhance SWM performance by decreasing reaction times. Accordingly, neural activity was reduced in relevant regions during encoding and retention stages, correlating with better performance. Notably, functional connectivity in IPL and surrounding regions was enhanced during retention. These findings indicate that TIS functions to improve the processing efficiency of the neural network for SWM in that less neural resources were needed and therefore recruited in relevant regions, and the functional connections became stronger among these regions. Our results are against the notion that TIS taxes more neural resources to supplement a cognitive task.