Finnish brain device interprets quadriplegic patient’s thoughts

Aim is to control simple computer applications such as electric wheelchair with power of thought

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Quadriplegic patients in the Käpylä Rehabilitation Centre in Helsinki have been involved in an exciting research project verging on science fiction.
      As part of a doctoral dissertation, a device that is able to “read” thoughts has been tested on the patients.
     
When the command that a patient is thinking is transferred through a computer to, say, an electric wheelchair, the chair will turn to the desired direction.
      In the same fashion, the power of thought can be used to control a computer, television, or any other electronic device.
      Laura Kauhanen, M.Sc. (Technology), will defend her doctoral thesis on the subject at the Helsinki University of Technology today, Friday.
     
In the EEG laboratory of the Helsinki University of Technology, Kauhanen demonstrates the pivotal instrument of the project, a headset that measures the electric activity of a person’s brain.
      The cap, which is held in place by a strap under the chin, has 32 measuring electrodes attached to it.
      A red LED light shines from each one of the electrodes.
     
The brain-computer interface (BCI) utilises a simple notion: when we think of something, this causes changes in the electric field of the brain.
      As a person thinks of the same thing several times, for example turning the wheelchair right, the attached computer “learns” to recognise the brain’s electric state caused by that particular thought and is then able to pass the correct command to the wheelchair. A primitive analogy might be the way in which voice-operated text processing software "learns" the user's speech patterns.
      This type of guidance system only became possible after the mid-1990s, when the processing speed of computers finally reached a sufficient level.
      According to the results of Kauhanen’s doctoral thesis, a quadriplegic patient’s brain signals differ from those of a healthy person. Hence future testing will have to concentrate on the actual target group. Test results received with healthy persons cannot be generalised or extrapolated with any great confidence.
     
So far the brain-computer interface can only be adapted to control very simple computer applications. Kauhanen is quick to dismiss some of the more pie-in-the-sky suggestions of a "thought-reading machine" that could even be used as a lie-detector. As yet, very little is still known of the immensely complex patterns of the human brain.
      According to Kauhanen, disabled people - who cannot use their limbs to operate devices - would reap the most benefit from the invention.


Links:
  Laura Kauhanen
  Kauhanen dissertation abstract

Helsingin Sanomat