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bioRxiv · 10.1101/2023.08.26.554639

Identifying critical language planning regions with direct electrical brain stimulation

Castellucci, G. A.·Kovach, C. K.·Tabasi, F.·Christianson, D.·Greenlee, J. D.·Long, M. A.
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Abstract

Many brain areas exhibit activity correlated with language planning1-9, but the impact of these dynamics on spoken interaction remains unclear. Here we use direct electrical stimulation to transiently perturb cortical function in neurosurgical patient-volunteers performing a question-answer task10. Stimulating structures involved in speech motor function evoked diverse articulatory deficits, while perturbations of caudal inferior and middle frontal gyri - which exhibit preparatory activity during conversational turn-taking - led to response errors. Perturbation of the same planning-related frontal regions slowed inter-speaker timing, while faster responses could result from stimulation of sites located in other areas. Taken together, these findings further indicate that caudal inferior and middle frontal gyri constitute a critical planning network essential for interactive language use1.

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Castellucci, G. A., Kovach, C. K., Tabasi, F., Christianson, D., Greenlee, J. D., Long, M. A.. 2023-08-28. Identifying critical language planning regions with direct electrical brain stimulation. https://doi.org/10.1101/2023.08.26.554639

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