Rapid Patient-Specific Brain Mapping for Neurosurgical Planning
Neurosurgical planning requires identifying brain regions that support critical cognitive and behavioral functions so care can be taken to preserve them during surgery. While there are broad similarities in functional anatomy across individuals, variations due to genetic, developmental, and neuropathological factors can all interact to produce substantial inter-individual variability in the functional organization of the brain. This variability can be particularly pronounced in patient populations because patient-specific pathological factors often produce unique reconfigurations of the brain’s functional networks. Therefore, maximizing post-surgical functional outcomes requires detailed pre-surgical mapping of the unique functional anatomy of each patient’s brain. The current “gold standard” for pre-surgical mapping, electro-cortical stimulation (ECS), involves temporarily disrupting activity in various cortical regions to identify neural populations that play critical roles in various diagnostic tasks. While this approach produces reliable patient-specific functional maps, its effectiveness can be limited due to prohibitively long acquisition time, ambiguities regarding stimulation parameters, and reliance on overt responses from patients. Here, we propose a plan to develop, validate, and clinically implement an electrocorticographical (ECoG) approach to pre-surgical mapping that allows for these weaknesses to be circumvented. Because ECoG allows for simultaneous recording from multiple sites throughout the brain, it is likely to be much more efficient than ECS, which requires sequential stimulation at each site. Moreover, because ECoG signals (a) are evoked even when patients do not respond overtly and (b) have similar spectrotemporal properties throughout the brain, this approach may be more effective than ECS when patient mobility is limited or when optimal stimulation parameters vary unpredictably across brain regions or individuals.