European engineers have developed a brain wave sensor that allows paralysed people to write.
The Mind Speller is a EEG-based (electroencephalogram-based) device that detects and interprets 'P300' event-related potentials in the brain signals of a person that is looking at a display presenting alternate rows and columns of characters (video).
"P300 potentials are often used as metrics of cognitive function in decision making processes," said Belgian research lab IMEC. "However, currently available P300 devices are large, expensive and uncomfortable in use. The Mind Speller, on the other hand, uses a portable device not larger than a matchbox, connected to a cap that contains electrodes located at specific positions on the head to capture the relevant signals."
Alongside IMEC in the project is Holst Centre in Eindhoven, and the lab of neuro- and psychophysiology at the Katholieke Universiteit Leuven.
The portable electronics box contains a proprietary low power 8-channel EEG-chip developed by IMEC and Holst Centre, a standard microcontroller to digitises the EEG signals, and a 2.4GHz radio which sends the signals to a PC.
The data is interpreted in the PC by a signal processing algorithms developed by the team of Professor Marc Van Hulle at the Katholieke Universiteit Leuven.
"The Mind Speller is a generic device that can be adjusted to different users. Therefore, it could be a communication solution for people with temporal impairments for whom the existing solutions are too expensive," said Van Hulle. "Moreover, it may help those patients that are not helped with the existing devices driven by motoric activity such as eye movement." 