Move over, Frankenstein: This electrode brain implant could someday shock you out of a coma

Hearing “coma” may be synonymous with “doom” in many cases, but that could change. Researchers at the University of Wisconsin-Madison have developed startlingly sci-fi new tech that sounds like something Mary Shelley might have dreamed up.

It involves using an electrode brain implant to zap a jolt of electricity to a highly specific area of the brain (which is often difficult to reach). While human experiments haven’t happened yet, trials performed on monkeys showed some promise for eventually pulling humans out of the chasm of a coma. This is the first time any primate has been roused from such a deep state of unconsciousness.

“Consciousness is the capacity to experience one’s environment and internal states,” said UW-Madison psychology and neuroscience professor Yuri Saalmaan in a study recently published in Neuron, adding that “Changes in consciousness coincide with state changes across sleep and wake cycles, traumatic brain injury, or exposure to a wide range of anesthetic agents.”

But first, something about the central lateral thalamus (CL). Saalmaan and his team found the CL to be essential to consciousness. It is located in the thalamus, two regions of gray matter through which signals from sensory nerves of the spinal cord and brain stem pass as they are transmitted to the cerebral cortex. When you see a disembodied brain in a horror movie, that labyrinth of gray matter that screams braaaaaiiiins to hungry zombies is actually the cerebral cortex, which is the epicenter of thinking and processing information. It also controls higher thought processes and — of course — consciousness.

“Our results suggest that CL has a special role to play in consciousness, as stimulations were most effective when centered on CL as opposed to neighboring thalamic areas,” Saalmaan said.

The central lateral thalamus lies deep in the brain’s core and sends messages to deep layers of the frontal and parietal (side) lobes of the cerebral cortex. This is why the CL is so important to consciousness, and in turn, the cortex has been shown to keep the CL active. Lesions in the CL are associated with coma and other lapses of consciousness. By stimulating that area and getting as close as possible to matching the level of CL activity while the subject is awake, Saalmann and his team were able to jolt deeply anesthetized monkeys out of their artificial unconsciousness. You just need to be dead on.

If you’re even a millimeter off or don’t apply electric bursts at the right frequency, you won’t get that Frankenstein-coming-to-life effect.

When the researchers got it exactly right and stimulated the CL of a monkey with the right frequency, the anesthetized animal would show conscious behavior like opening its eyes, reaching for things and other facial and bodily movements that clearly showed it was awake. It would instantly fall unconscious again almost immediately after stimulation was stopped. This is more than just flipping a switch on and off. It requires an insane level of precision, and more tests will need to be performed on animals before the method can be tried on human subjects.

“Our study provides…evidence for a circuit-level mechanism of consciousness with special emphasis on the reciprocal interaction between CL and deep cortical layers,” said Saalmaan.

As for putting together a creature from cadaver parts and bringing it through life with high voltage, that won’t be happening anytime soon — or hopefully ever.

(via University of Wisconsin-Madison/Neuron)