Towards localization of transcranial magnetic stimulation inside the MRI scanner

Background and Motivations: Transcranial magnetic stimulation (TMS) has been used as a non-invasive tool in various neuroscience applications including investigating brain functions, serving as a clinical diagnostic tool and as a therapy for several neuropsychiatric disorders [1]. TMS delivers time-pulse magnetic fields created by special coils to induce local currents in the tissue i.e., neuronal depolarization. Regardless of its expanding applications, TMS studies face the general problem of positioning the magnetic coil above relevant intended areas [2]. Currently, the standard localization is based on optically tracked frameless stereotaxic neuronavigation systems [1]. The precision of these methods are rather limited that the inconsistency of the coil placements may lead to the different results in repeated therapeutic studies [3]. In this work, we propose a new method of localizing the TMS stimulation by using MRI to map and visualize its magnetic field.