Transcranial temporal interference stimulation (tTIS) has recently emerged as a non-invasive neuromodulation method aimed at reaching deeper brain regions without affecting the overlying cortex. However, many questions about its effects remain, requiring further experimental investigation. This project aims to stimulate the median nerve to assess the motor and cortical effects of tTIS and its stimulation parameters. In addition, a simulation study will quantify how uncertainty in tissue conductivity values affects predicted stimulation targets and the reliability of optimization outcomes.