generates conscious experiences. Some doubt whether the objective tools of
science can ever get to grips with a phenomenon that is so subjective. Even
so, researchers have begun to identify the changes in brain activity that
accompany awareness, and they also have some fascinating ideas about why
consciousness evolved.
How the brain conjures conscious awareness from the electrical activity of
billions of individual nerve cells remains one of the great unanswered
questions of life.Each of us knows that we are conscious, in terms of
having thoughts, perceptions, and feelings, but we are unable to prove it
to anyone else. Only we have access to the mysterious essence that allows
us to experience those thoughts, perceptions, and feelings.
In the 1990s, the philosopher David Chalmers described this inaccessibility
to external, objective scrutiny as the “hard problem” of consciousness.He
proposed that an easier task for scientists to tackle would be its “neural
correlates” — where and how brain activity changes when people have
conscious experiences.
Apart from curiosity, scientists are most likely motivated to discover the
neural correlates of consciousness in order to help diagnose and treat
disorders of consciousness, such as persistent vegetative states and some
psychiatric disorders.
