Team has wireless on the brain

Researchers are attempting to develop the smallest and the least power-hungry device for remotely measuring the electrical activity of patients’ brains.

A team from IMEC, a European nanoelectronics research centre, and the Holst Centre, a wireless technology R&D organisation, have unveiled a prototype of its wireless eight-channel EEG (Electroencephalography) system.

The device is based around an ultra-low-power analogue readout ASIC (application-specific integrated circuit). The electronics, which include ASIC, radio and controller chips, are integrated on a printed circuit board measuring 47mm by 27mm.

It is claimed the packaged system consumes only 1.8mA, allowing about three days of unplugged use with a 160mAh Li-ion battery.

The device wirelessly monitors brain activity using electrodes attached to a patient’s scalp. Information on the electrical activity — caused by neurons firing in the brain — is wirelessly transmitted in real time to a receiver up to 10m away.

IMEC-developed algorithms interpret the brain signals to make links between brain activity and the degree of relaxation.

Applications for the EEG system could range from ambulatory monitoring of epileptic patients to e-learning and gaming.

Julien Penders, programmer manager for body area networks at IMEC in Belgium, said researchers there plan to make improvements to the prototype before beginning pre-clinical trials late next year.

The improvements, he added, include ways to make the electrodes easier to stick to the scalp without affecting signal output.

Penders said the IMEC team is developing an EEG headset that could be easily slipped onto a patient’s head without assistance.

Siobhan Wagner