Can consciousness be switched on and off?

Clap on, clap off awareness.


Asked by: Louisa Offen, Poole

Yes, if a recent experiment is to be believed. In an attempt to locate the source of an epileptic patient’s seizures, doctors at George Washington University, USA, inserted electrodes into her brain. One electrode was positioned close to the claustrum, a thin sheet of tissue below the cortex with a role akin to that of an orchestra’s conductor – coordinating the many different things that go on in the brain at once. Consciousness typically involves sights, sounds, thoughts and feelings all coming together. Could the claustrum be what makes this possible?

When the doctors stimulated this electrode the woman stayed awake but lost consciousness. She stopped what she was doing, stared blankly into space and would not respond to them. When the stimulation stopped she regained consciousness. It seems a whole, complex brain is needed for rich experiences, but it also needs the claustrum ‘switch’ to bring everything together.

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