“It’s my personal hope, it’s my team’s hope, that using this novel technique to better understand people’s language networks, that we’ll be able to offer them epilepsy surgery that is safer and more effective in rendering them seizure free.”
Watch the full interview with Dr Parveen Sagar below.
Project Summary:
Focal epilepsy is a neurological disorder in which seizures originate from a specific brain region. About one third of patients do not achieve seizure freedom with medication, and for these individuals, surgery offers the best chance of long-term control. However, surgery can impair essential functions like speech and communication, making accurate mapping of language areas critical.
Stereo-electroencephalography (SEEG) uses implanted electrodes to record electrical activity and localize seizure onset zones. These electrodes can also map language regions. Traditionally, direct electrical stimulation (DES) is applied to temporarily disrupt brain activity and identify language-critical areas. DES is time-intensive, fatiguing, and may provoke seizures, yet language decline still occurs in up to 50% of patients, highlighting the need for more sensitive, patient-friendly approaches.
This study evaluates the use of task-induced high-frequency activity (HFA) recorded with SEEG for mapping language function. HFA, which reflects brief bursts of brain activity, can be detected while patients perform naming tasks, potentially identifying language regions without the need for DES. We will compare HFA with DES results and assess whether resecting HFA-positive areas impacts language outcomes after surgery.
When we piloted this method in 23 patients, we found that HFA closely matched DES-identified language areas. Expanding on this work, our project aims to develop a safer, faster, and more patient-friendly framework for mapping language during SEEG, improving surgical planning and outcomes. HFA mapping could make epilepsy surgery safer, more accessible, and better tailored to individual patients.
The Brain Foundation is dedicated to funding the next generation of Australian research into brain disorders, diseases, and injuries, with the ultimate goal of advancing diagnoses, treatments, and patient outcomes.