Scientists explore the meaning of self-consciousness

US SCIENCE CONFERENCE:SCIENTISTS IN Switzerland are exploring the meaning of self-consciousness and the mind in a completely new way. They are using virtual reality and computerised "virtual humans" to learn how the self can be altered.

Details of the work headed by Prof Olaf Blanke of the Brain Mind Institute at the École Polytechnique Fédérale de Lausanne were presented yesterday at the annual meeting of the American Association for the Advancement of Science (AAAS) in Washington DC.

His work formed part of a session entitled “Mind and Machine” in which researchers explained how damaged nerves spliced into healthy muscle tissue could drive artificial limbs by subjects thinking about moving missing limbs.

There was also a radio-controlled robot controlled by nothing more than the power of thought.

The development of “smart” artificial limbs controlled directly by existing nerves represented a promising response to limb loss, said Dr Todd Kuiken of Northwestern University and the Rehabilitation Institute of Chicago.

Targeted muscle reinnervation involves splicing into nearby muscle with the unused but healthy nerves left after amputation. The patient can be trained to send signals along the nerves to flex the elbow joint, turn the wrist and grasp with the fingers. Researchers are also seeking to return sensory response to amputees in an approach known as targeted sensory reinnervation.

Prof José del R Millán, also of the École Polytechnique, uses a cap that can read brainwaves. The subject is trained to operate a radio-controlled robot that moves across the floor by thinking specific thoughts. Such a system could be used for patient locomotion or to control the local environment.

Prof Blanke explained how he was using brain-imaging technology to identify parts of the brain associated with our understanding of self. Subjects wear virtual-reality headsets and are exposed to 3D environments that allow them to become avatars, or virtual humans.

He and his team used this to challenge fundamental aspects of self-consciousness, for example putting male subjects inside female avatars or changing the subject’s perspective from first-person “I” to third-person “he”. They also physically touched the subjects, sometimes matching the virtual world and sometimes out of step with the avatar, and studied how the brain responded.

The researchers compared their results with data from neurological patients who reported out-of-body experiences and found matching activity in parts of the brain associated with touch and vision. Prof Blanke believes the work may lead to the discovery of what causes self-consciousness.