The Netherlands, 8th February – The Holst Centre has made significant breakthroughs in enabling technologies for wireless EEG (electroencephalogram) systems, enabling continuous ambulatory monitoring. Its prototype EEG headset is compatible with dry electrodes and combines ease-of-use with ultra-low power electronics. The headset records high quality EEG signals and wirelessly transmits the data in real-time to a receiver located up to 10m from the system.Applications that can be envisaged with this EEG prototype system include entertainment and infotainment, for example adaptive game environment reacting to the player’s cognitive state, or e-learning where the difficulty can be adapted based on cognitive load; lifestyle, such as neuro-feedback; safety, for example monitoring drowsiness of drivers or cognitive load of occupational health services in action; and medical such as early warning system for epileptic patients or brain typing enabling people with motoric disabilities to communicate.
At the heart of the system is an 8-channel ultra-low-power analog readout ASIC. The ultra-low power readout ASIC consumes only 200µW and features high common mode rejection ratio (CMRR) of 120dB and low noise (input referred noise of 55nV/√Hz). These performances are achieved at high input impedance (1GΩ), which makes it compatible with the use of dry electrodes. The electronics, including ASIC, radio, and controller chips are integrated in a small wireless EEG system of 25mmx35mmx5mm dimensions, that can easily be embedded in headsets, helmets or other accessories. The signal to noise ratio of the system is 25dB on real EEG signals. The entire system consumes only 3.3mW for continuous recording and wireless transmission of 1 channel, and 9.2mW for 8 channels. This gives between 1.5 to 4 days of autonomy on a small 100mAh Li-ion battery, depending on the mode of operation.