Poster D64, Wednesday, August 21, 2019, 5:15 – 7:00 pm, Restaurant Hall
Neural correlates of American Sign Language production revealed by electrocorticography
Jennifer Shum1, Lora Fanda1, Beenish Mahmood1, Daniel Friedman1, Patricia Dugan1, Werner K. Doyle1, Devinsky Orrin1, Flinker Adeen1;1New York University School of Medicine
The spatiotemporal dynamics underlying sign language production remains difficult to study as the majority of the literature in this area uses techniques with limitations in either spatial or temporal resolution. Here we report a unique case of electrocorticography (ECoG) recordings obtained from a neurosurgical patient with intact hearing and bilingual in English and American Sign Language (ASL). The patient suffered from pharmaco-resistant epilepsy requiring surgical implantation of electrodes in the left hemisphere to clinically identify seizure onset zones. We designed a battery of clinically relevant cognitive tasks to capture multiple modalities of language processing and production and which mirrored the clinical paradigms employed during electrical stimulation mapping. The tasks involved picture naming, visual word reading, auditory word repetition, auditory naming, and auditory sentence completion, with the patient either responding in spoken English or ASL. We focused our analyses on changes in high gamma activity as this has been previously shown to be a robust marker of local cortical activity. Here we show activation maps during ASL and speech processing, identify regions with preferential activity during ASL versus speech production, and show the neural propagation map during ASL output. The patient also underwent electrical stimulation mapping, which revealed face and limb sensorimotor findings that matched with preferentially active ASL and speech production regions, respectively. To our knowledge, this study is the most extensive investigation into the spatiotemporal differences between a spoken and signed language utilizing direct cortical recordings in a hearing intact ASL bilingual patient, and offers a unique window into the neural underpinnings of ASL and speech production.
Themes: Signed Language and Gesture, Language Production
Method: Electrophysiology (MEG/EEG/ECOG)