Understanding the Brain's Response to TMS with EEG
How TMS interacts with the brain
Recent advances in the way we measure brain activity has broadened our understanding of healthy and unhealthy brain function. This information is leading to new and successful treatments in a wide range of disciplines like psychology, psychiatry, neurology and neurorehabilitation. One of the most remarkable advances in this field has been the introduction of transcranial magnetic stimulation (TMS), which is a non-invasive method of applying a brief and localized magnetic pulse through the scalp to activate underlying brain cells. The responses to this intervention carry valuable information about the functional and structural properties of the brain.
To study the evoked responses, TMS is always used in combination with a tool to record neural activity. Conventionally, brain responses to TMS pulses are evaluated by using electrodes to record muscle activity. However, this approach is limited to the motor area of the brain and therefore cannot examine other regions which are of interest to psychiatric and neurological disorders.
We are investigating a new approach which has been developed to allow recording of brain responses following stimulation of both motor and non-motor areas. This technique combines TMS with electroencephalography (EEG), a method which records small fluctuations in brain excitability from electrodes placed on the scalp. Combined TMS-EEG has enormous potential as a powerful and easy-to-use diagnostic and therapeutic tool in a wide range of brain disorders. However, the TMS-EEG method is in early stages and the meaning of the recorded signals are not clearly understood. This project aims to investigate the neural mechanisms underlying these responses and characterize different components of the evoked signals, helping to fully exploit the potentials of this method in both research and clinical settings.