A new study has identified an on-off switch in the human brain that could control a person's consciousness.
According to CBS News, the researchers tracked brain activity of a 54-year-old woman with intractable epilepsy by inserting electrodes in her brain. They made their discovery while trying to identify where her seizures came from using an electrical stimulation method.
When they stimulated the claustrum, a thin layer of neurons in the center neocortex region of the brain, they found they were disrupting the woman's normal consciousness. When the researchers shut off the electrons, ending the electrical stimulation, the woman returned to consciousness and could not recall what had just happened.
"The claustrum could constitute a common gate to the 'external' and 'internal' awareness networks," reads the study, published in the journal Epilepsy and Behavior. "This could explain why the electrical stimulation of the claustrum, and the resulting alteration of its normal function, would cause an impairment of consciousness, including an absence of recollection of the external events and of internal/interoceptive experience."
Electronic stimulation is being tested with patients who suffer from Parkinson's disease, Alzheimer's disease and dystonia (involuntary movements). The method is also showing early promise with patients suffering from depression, but the scientists say identifying this switch could help treat various other neurological disorders.
Study lead author Mohamad Koubeissi, of George Washington University in Washington D.C., told New Scientist he "would liken [the claustrum] to a car."
"A car on the road has many parts that facilitate its movement - the gas, the transmission, the engine - but there's only one spot where you turn the key and it all switches on and works together," he said. "So while consciousness is a complicated process created via many structures and networks - we may have found the key."
Study co-author Christof Koch, of the Allen Institute for Brain Science in Seattle, said the new research could open all sorts of doors in the field.
"Ultimately, if we know how consciousness is created and which parts of the brain are involved then we can understand who has it and who doesn't," he told New Scientist. "Do robots have it? Do fetuses? Does a cat or dog or worm? This study is incredibly intriguing but it is one brick in a large edifice of consciousness that we're trying to build."
