Portable mind-reader lets users write with their thoughts

Posted by Emma Woollacott

European scientists have developed the first portable device that allows users to type merely by thinking.

The Mind Speller, intended primarily for people with severe motor disabilities, is an EEG-based device that interprets brain waves to spell words and phrases.

It uses a device no larger than a matchbox, connected to a cap that contains electrodes located at specific positions on the head to capture the relevant EEG-signals.

The Mind Speller contains a proprietary ultra-low power eight-channel EEG chip  developed by IMEC and Holst Centre to process the EEG signals. A commercially available low power microcontroller digitizes the EEG signals, and a low power 2.4GHz radio transmits the EEG signals wirelessly to a nearby PC.

The data is interpreted on the PC by signal processing algorithms developed at the Katholieke Universiteit Leuven.

Similar communication devices use either eye-tracking technology or laser pointing. However, they are subject to long calibration procedures and are very expensive.

"With a much simpler design, relying on a power-efficient on-chip implementation, the Mind Speller is the first step in the development of a generic, easy-to-wear, accurate and cost-efficient communication solution for people with motoric disabilities," says Chris Van Hoof, Program Director at IMEC.

"Currently, we are adapting the electronics to work with dry electrodes, making the system even more unobtrusive."