Tao Zou1,2,Na Xiao1,2,Paddy K. L. Chan1,2
University of Hong Kong1,Advanced Biomedical Instrumentation Centre Limited2
Tao Zou1,2,Na Xiao1,2,Paddy K. L. Chan1,2
University of Hong Kong1,Advanced Biomedical Instrumentation Centre Limited2
Electrocorticographic Brain-Computer Interface (ECoG-BCI) has significantly contributed to both fundamental neuroscience research and clinical applications, including brain function recovery, speech neuroprostheses, epilepsy detection, and traumatic brain injury prognosis. Improving the recording coverage and density of ECoG-BCI are particularly valuable for analysing the activities correlations among the multiple brain regions and identifying the actual neural disease foci accurately. Traditionally, the deployment of large-area coverage devices commonly necessitates an equally substantial cranial opening, which expose significant brain tissue and could potentially cause brain tissue swelling, inflammation, heighten risk of cortical damage, and infection. As a result, diminishing the acceptance of these implants among BCI users.<br/><br/>Here we present a deployable ECoG-BCI platform operated via magnetically controlled guidewires in minimally invasive appraoch. The ECoG-BCI platform comprises a high-density array of flexible PEDOT:PSS/pHEMA electrodes (28.4 electrodes cm<sup>-2</sup>) covering a large surface area (9 cm<sup>2</sup>), sub-millimeter soft magnetic polymer guidewires, a robotic arm equipped with a permanent magnet for guiding the magnetic guidewire, and an automatic control system. The folded flexible electrode array can traverse the craniotomy and be unfurled by tracking the guidewires. The thin, 10 μm thick parylence based electrode array, featuring perfusion holes, ensures excellent conformability and close contact with the curved brain surface. We deploy the proposed ECoG-BCI platform within area V1 of the visual cortex in a macaca fascicularis, demonstrating chronic neural signal recording and cortical electrical stimulation capabilities. The monkey has responses to the phosphenes induced by the visual cortex stimulation. This deployable ECoG-BCI platform has the potential to restore effective vision for the blind with minimal invasive implantation injury.