How Does It Feel To Have Half a Brain? Not Bad, Actually

“Patient R” is missing three key parts of his brain, and yet he’s conscious and self-aware

Brad Lauster

“Patients with no insula should be like zombies,” says David Rudrauf to New Scientist, referring to the insular cortex, a part of the brain usually associated with consciousness and emotions. But there is a big difference between should be and are. In Scientific American, Ferris Jabr introduces us to Roger, or “Patient R.” Roger is missing not only the bulk of his insular cortex, but also his anterior cingulate cortex, and his medial prefrontal cortex. Despite the missing bits, Roger isn’t a zombie. In fact, he functions quite well, all things considered.

Roger is missing his anterior cingulate cortex
Roger is missing his anterior cingulate cortex (left), his medial prefrontal cortex (middle), and most of his insular cortex (right). Geoff B Hall / Anatomography / Wikimedia Commons

In 1980, says Jabr, a serious bout of herpes caused Roger’s brain to swell and decay. The large amounts of brain damage he suffered should have left him in a zombie-like trance, but it didn’t. Instead, Roger’s ailment left him with a mixed bag of cognitive processes.

Roger cannot remember much of what happened to him between 1970 and 1980 and he has great difficulty forming new memories. He cannot taste or smell either. But he still knows who he is—he has a sense of self. He recognizes himself in the mirror and in photographs. To most people, Roger seems like a relatively typical man who does not act out of the ordinary.

He knows who he is, he knows what he wants, he cracks jokes, and he can think from other people’s perspectives. But most importantly from a scientific perspective, Roger’s ravaged brain is changing the way we think about things such as consciousness and self-awareness.

Roger, “who is self-aware – despite lacking three regions of the brain thought to be essential for self-awareness – demonstrates that the mind remains as elusive as ever,” says Douglas Heaven in New Scientist.

The finding suggests that mental functions might not be tied to fixed brain regions. Instead, the mind might be more like a virtual machine running on distributed computers, with brain resources allocated in a flexible manner.

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