TARGETING THE INSULA WITH TEMPORAL INTERFERENCE STIMULATION

Temporal Interference Stimulation (TIS) is an emerging non-invasive brain stimulation method that enables the modulation of neural activity in deep brain structures while minimizing exposure of superficial tissues. Because the insula is critically involved in pain perception, we aim to validate TIS for the modulation of neural activity in this region. The project includes both computational and experimental components.
First, we used Finite Element Modeling (FEM) to simulate electric fields for multiple electrode montages and to compute TIS envelopes. We extracted ROI-specific metrics to assess the exposure, selectivity relative to the overlying cortex, and unintended stimulation of neighboring regions associated with the insula. We repeated this process using structural MRI data from 20 healthy participants, and for each we identified the best TIS configuration using a ranking system. From these individual montages, we derived the optimized universal montage for group-level testing.
In a following step, we will conduct a concurrent TIS-fMRI study to test whether the optimized TIS montage induces significant modulation in the BOLD activity and functional connectivity in the insula. This experiment will include both measurements of brain activity during resting-state and while experiencing tonic heat pain to quantify the effects of TIS at rest and during sustained nociceptive processing.
In summary, this project aims to validate the use of TIS to target the human insula. The results will demonstrate the potential of this technique for modulating deep brain regions, establishing the foundation for future TIS studies to probe the involvement of the insula in pain perception.