Application — Cortical surface
Real-time Mandarin speech decoding with a 256-channel flexible ECoG array (2025)
Lab or organization
Real-time Mandarin speech decoding, 256-channel flexible ECoG (2025)
The peer-reviewed decoding study for NeuroXess’s 256-channel flexible ECoG array, with company-announced companion cases listed separately. Where the company announcement and Chinese state reporting conflict, both figures are given.
Study facts
| Field | Value and source scope |
|---|---|
| Publication | ”Real-time decoding of full-spectrum Chinese using brain-computer interface”, Science Advances, published November 7, 2025 [1] |
| Setting and approval | Huashan Hospital, Fudan University; IRB approval KY2024-842 [1] |
| Subjects | The paper reports one 43-year-old woman [1]. Company announcements add a 21-year-old epilepsy patient (motor decoding, August 2024) and a tumor-epilepsy patient (language area, December 2024) [2]; Chinese-language reporting adds a third case, a 19-year-old with right frontal lobe epilepsy [4] |
| Signal and task | High-gamma cortical activity (70 to 150 Hz); real-time decoding of Mandarin syllables and of motor intent [1][2] |
| Peer-reviewed result | Median offline accuracy of 71.2% over 394 Mandarin syllables in a single-character reading task [1] |
| Company-reported results | 71.2% accuracy across 142 common syllables, decoding latency under 100 ms per character, motor decoding latency under 60 ms [2]. Timing conflict as published: the company’s English announcement says the 142-syllable result came within five days [2]; Jiefang Daily reports about 71 percent on 142 syllables seven days after surgery [3]. Chinese release for the 19-year-old: 4.07 bits per second cursor control after 19.87 hours of training, from local field potentials with a position-velocity Kalman filter [4] |
| Data quality | About 9 hours of data over 11 days of monitoring; no new bad channels emerged [1] |
| Key limitations | Patients were temporarily implanted during clinical epilepsy or tumor care, not chronically implanted paralyzed users; few subjects; company announcements are not peer reviewed [1][2] |
Primary sources
- Real-time decoding of full-spectrum Chinese using brain-computer interface, Science Advances, November 7, 2025. Peer-reviewed.
- NeuroXess, Major Breakthrough in Clinical Trials of High-Throughput Implantable Flexible BCI, January 2, 2025. Company announcement.
- Shanghai Municipal Government, from Jiefang Daily (Chinese). Flexible BCI decodes Chinese speech, January 5, 2025.
- Sina Finance (Chinese). NeuroXess third patient release, April 17, 2025.