A Stable Mind
Anil Ananthaswamy, New Scientist, 11 April 2015
Summary and review of the above article
A recent study by Aaron Schurger of the Swiss Federal Institute of Technology suggests that for conscious perception to occur brain activity has to be stabilised for some hundreds of milliseconds. In Schurger’s study, subjects saw a red-on-green line drawing in one eye, but a green-on-red drawing in the other eye. As a result, they sometimes saw a drawing, and sometimes failed to see a drawing. However, when they did report seeing a drawing, scans showed a stable level of brain activity, but when they failed to see a drawing brain activity was much more variable. A repetition of this study utilizing more sophisticated scanning equipment that had temporal accuracy over milliseconds confirmed the earlier indication that conscious perception required stability in brain activity.
A further study involved patients who were in a vegetative state, minimally conscious, or had just recovered from coma. The ability of the subjects’ to achieve a stable brain state correlated with their condition, with the more conscious patients achieving greater stability; thus stability is taken as an indicator of the state of consciousness.