Season 17, Episode 9: Is There Any Evidence That Consciousness is Quantum?

Hey StarTalkians! Following on from the previous post, let’s continue the deep dive in quantum consciousness. Episode 9 of Season 17 saw Neil, Chuck, Gary O’Reilly and guest Charles Liu answer some “Cosmic Queries,” and in the process, they wandered into the minefield that is quantum consciousness:

The Problem With Uploading Your Consciousness | Cosmic Queries #105

Previously, we covered Roger Penrose’s well-known quantum consciousness theory, called Orch OR, and why it doesn’t seem so likely at first glance. But we know what matters: the evidence.

So, is there any?

Microtubules and Anaesthesia

Some “evidence” of quantum consciousness is more about confirming related predictions of the theory. The first example paper is like this.

This paper builds on the idea from Penrose and Hameroff, that small structures called microtubules might be crucial for quantum consciousness. In line with this, the authors found that rats given microtubule-stabilizing drugs stayed awake longer after anaesthesia than control rats.

This could be understood as a confirmation of the Orch OR prediction that consciousness originates from stable vibrations of these microtubules. However, the authors add that their results are also “potentially consistent with classical models of consciousness.”

Quantum Effects in Microtubules

Penrose and Hameroff drew attention to the results from a Japanese team , who found evidence for quantum effects in microtubules.

Broadly, the team found AC conductance through 25 nanometre diameter microtubules was greater than through 4 nanometre microtubules. The authors were interested in resonance within the microtubules, which Penrose and Hameroff called evidence of “cooperative, possibly quantum coherent effects.”

Spin-Spin Interactions in the Brain

Finally, a 2022 paper boldly claimed to find “non classical brain functions.” The authors created an interaction between a known quantum system and an unknown one (the brain). They observed some potentials on MRI scans which are not usually detectable. After some investigation, they concluded that quantum effects in the brain must have been responsible. 

These and some other results (e.g. super-radiance) are intriguing, but not as exciting as they sound. All sufficiently small structures display quantum effects – that’s why quantum mechanics exists – but it doesn’t mean they create consciousness. As one response to Penrose and Hameroff points out , without identifying a definitive mechanism, this is all essentially idle speculation.