A new study published in the peer-reviewed Journal of Physics Communications suggests that the human brain has much in common with a quantum computer. Experts say it’s part of a growing body of evidence that quantum mechanisms could explain how the brain works. “Understanding quantum computing and the associated algorithms could reveal some of the deeper workings in the brain,” Malik Magdon-Ismail, a professor of computer science at Rensselaer Polytechnic Institute, told Lifewire in an email interview.
Quantum Thoughts
In their recent paper, researchers from Trinity College Dublin in Ireland found that human brains could use quantum computation. They developed the theory after adapting an idea designed to prove the existence of quantum gravity to explore the human brain. The scientists measured brain functions correlated with short-term memory performance and conscious awareness. The results, they claim, suggest quantum processes are part of cognitive and conscious brain functions. “We adapted an idea, developed for experiments to prove the existence of quantum gravity, whereby you take known quantum systems, which interact with an unknown system,” Christian Kerskens, the co-author of the research article, said in a news release. “If the known systems entangle, the unknown must be a quantum system, too. It circumvents the difficulties of finding measuring devices for something we know nothing about.” To test their theory, the researchers tested fluid found naturally in the brain and measured the spin of protons in the liquid. Then, using a specific MRI design to seek entangled spins, they found signals that resemble heartbeat-evoked potentials, a form of EEG signals. Electrophysiological potentials like the heartbeat-evoked potentials usually are not detectable with MRI, and the scientists believe they could only observe them because the nuclear proton spins in the brain were entangled. “If entanglement is the only possible explanation here, then that would mean that brain processes must have interacted with the nuclear spins, mediating the entanglement between the nuclear spins,” Kerskens said. “As a result, we can deduce that those brain functions must be quantum.”
The Key to Faster Computers?
Quantum computing is a hot topic, with companies like IBM spending billions on developing practical quantum computers. “Quantum-state entanglement is the most important aspect of nature that allow quantum computers (so far, only in theory) to vastly outperform classical conventional digital computers on certain (not all) tasks,” Michael Raymer, a professor of physics at the University of Oregon, Eugene told Lifewire in an email. As a reminder for those who skipped the subject in school, quantum mechanics refers to the behavior of objects at the subatomic scale. The theory underlying quantum mechanics also implies that particles can act as waves and exist simultaneously in two places. “It is a similar parallelism that quantum computers exploit to do things faster,” Magdon-Ismail said. “If you can simultaneously explore all paths from Albany to NYC in parallel, you can find the shortest path much more quickly than if you are limited to trying each path one after another.” Kerskens pointed out that quantum processes could explain how human brains can outperform supercomputers in certain circumstances. He said his study’s results could help build even more advanced quantum computers. Magdon-Ismail agreed, saying that one explanation for the astonishing capabilities of the human brain is that it is exploiting similar quantum parallelism in its computing architecture. “We may never know what algorithms, quantum or other, that the brain uses, but we can try to establish that the brain, though a macroscopic object, is quantum mechanical in nature,” Magdon-Ismail added. Magdon-Ismail warned that more studies must be conducted before there will be a final word on quantum effects in the brain. “But, if the brain truly does exploit quantum mechanical phenomena, then it raises the stakes on quantum computing research,” Magdon-Ismail added. “Understanding quantum computing and the associated algorithms could reveal some of the deeper workings in the brain. It’s food for thought.”
