1. Department of Electrical and Electronic Engineering The University of Hong Kong Pokfulam Road Hong Kong 999077 China
2. Department of Electronic Engineering The Chinese University of Hong Kong Shatin New Territories Hong Kong 999077 China
3. Institute for Translational Brain Research Shanghai Medical College Fudan University Shanghai 200032 China
4. Advanced Biomedical Instrumentation Centre Hong Kong Science Park Shatin New Territories Hong Kong 999077 China