Standing next to Prof. Dr.-Ing. Ivan Voloysak is a large, shiny chessboard made of acrylic glass with the usual chess pieces on it. Cables lead from the board to technical components such as a microcontroller board and a computer.
‘Moving the pieces requires more than just the power of thought. We can communicate the desired moves with our brain signals, but to do so we need a connection between the brain and the chess game,’ explains Ivan Volosyak.
This connection is established with the help of electroencephalography (EEG). EEG is a non-invasive, painless examination method that is used, for example, to diagnose brain damage. In the BCI laboratory, the focus is on a different purpose: ‘We do not intend to offer diagnostic examinations, nor are we able to do so. BCI stands for brain-computer interface. We want to give people the opportunity to interact with their environment with the help of a computer.’ Possible applications include controlling robots or prostheses – or even chess pieces.
Here’s how it works: the squares on the chessboard (and any semi-transparent chess pieces on them) flicker at different frequencies. When you look at a selected square, the nerve cells in your brain generate corresponding electrical signals. When these are measured with EEG electrodes, the computer can clearly identify and select the chess piece you are looking at. The electrodes are usually attached to an EEG cap. To provide the necessary conductivity, a gel is applied to the scalp.
Ivan Volosyak laughs: ‘The gel is easy to wash out. We have set up a small hair salon for our test subjects in the immediate vicinity of our laboratory.’
Then he turns serious: ‘Many people are familiar with EEGs from neurological examinations. They can neither read nor record thoughts. And we cannot use them to send signals to the brain or implant thoughts.’ It is a one-way communication from nerve cells to the computer via the electrodes. Nevertheless, unfortunately, the topic of brain-computer interfaces repeatedly gives rise to conspiracy theories, some of which end in real threat scenarios.
‘Anyone who would like to try it out for themselves is welcome to participate as a test subject. In order to improve our research system, it is necessary to examine the EEG signals of several test subjects,’ says Ivan Volosyak, encouraging people to visit the BCI laboratory.