The Center for Innovation in Neuroscience and Technology (CINT) is actively pursuing novel methods to map brain function. A challenge in the surgical treatment of brain tumors or focal epilepsy is to preserve the eloquent areas of brain function while at the same time maximizing the extent of resection to optimize long-term outcome. There is enough variation in functional anatomy for speech and motor sites among different individuals that precise localization requires cortical mapping using electrophysiological techniques.
The gold standard for cortical mapping, direct electrocortical stimulation (DECS), has a long history of application in the practice of neurosurgery. Its utility in improving functional outcomes in brain tumor surgery has been demonstrated, but potential side effects remain a significant concern. Specifically, after-discharges, seizures and distant-site stimulation may result in poor functional localization. Although several less invasive alternatives to DECS have been explored, such as fMRI and PET, they are not yet practical enough for widespread routine use.
The lab of CINT Director Eric Leuthardt, MD, is developing effective localization techniques that identify cortical activations associated with various speech and motor tasks both passively (by looking at the brain signals alone without stimulation) and in real time. Additionally, the lab is further developing techniques that can identify important functional regions from baseline brain activity. Locating functional regions in the brain without the need for patients’ participation or even their consciousness, which can also be done completely passively, is a marked innovation when compared to current brain-mapping approaches.
To date, all imaging techniques that locate function have had substantial participation requirements. By defining important areas of brain function through resting state cortical physiology alone, these results will have an important positive impact by providing mapping capabilities with the patient under anesthesia that are otherwise not possible. In doing so, this technology would enable us to map a broader group of patients who would otherwise not be surgical candidates.