Christof Koch is a neuroscientist distinguished by his rock-solid scientific work and romantic yearning to understand consciousness. He recently closed an essay by wondering: “What is it about the brain, the most complex piece of active matter in the known universe, that turns its activity into the feeling of life itself?” No coincidence with that phrasing—The Feeling of Life Itself is his latest book. He argues that consciousness is produced by the brain but that it’s also more widespread in nature than we might suppose.
His essay described new experimental work, from Stanford neuroscientist Kieran Fox and his colleagues, that explored the effects of electrically stimulating the brain, which revealed an ordering principle. That is, the more removed from sensory input or motor output structures a brain region is, the less likely it is that it contributes to our subjective experience. The “exacting data,” Koch wrote, “provides critical causal, not just observational, evidence to identify the neuronal correlates of consciousness.”
Neuronal correlates of consciousness are the parts of the brain thought to be required for consciousness to occur. The idea that there are only neuronal correlates of consciousness, and that these correlates are the patterns of synaptic firing in specific parts of the brain, is what you might call the conventional view in neuroscience. If we peer deeply into the brain, in other words, what we’ll find is that electrochemical synapse firings—produced by neurons of various types—are responsible for, as Koch puts it, the feeling of life itself, consciousness.
“It was a jaw-dropping moment, for us and for every scientist we told about this so far.”
But what if there’s more to the story? What if the electromagnetic fields generated by, but which are not identical to, the neuroanatomy of the brain, are in fact the primary seat of consciousness? The brain’s fields are generated by various physiological processes in the brain, but primarily by trans-membrane currents moving through neurons. These fields are always oscillating and they come in various speeds, clustered around certain bands, from delta on the lower end at 1-2.5 cycles (oscillations) per second (Hertz) up to gamma at 40-120 cycles per second.
Some neuroscientists have long considered the brain’s oscillating electromagnetic fields to be interesting but merely “epiphenomenal” features of the brain—like a train whistle on a steam-powered locomotive. Electromagnetic fields may just be noise that doesn’t affect the workings of the brain. Koch still seems to lean this way.
“While at this early stage of the exploration of the brain it would be foolish to categorically rule out any physical process,” he told me, “as an electrophysiologist I’m less enthused about ascribing specific functions to specific frequency bands, let alone experience. The causal actors between neurons that act at the time scale relevant for consciousness (5-500 milliseconds) are action potentials that cause, in turn, synaptic release of packets of neurotransmitters.” He thinks the extent to which oscillations affect neuronal firing patterns remains an open question. “Consider the sounds the beating heart makes,” he said. “These can be picked up by a stethoscope and can be used to diagnose cardiac conditions. However, there is no evidence that the body exploits these sounds for any function.”
I asked Wolfgang Klimesch, a professor at the University of Salzburg, what he thought about Koch’s view on electromagnetic fields. Klimesch developed the “binary hierarchy brain-body oscillation theory,” which says that consciousness is a function of various levels of resonance both within the brain and between the brain and various other organs, like the heart and stomach.
“With respect to Christof’s view that they are too weak in order to play a role for higher brain functions, he is right if one looks at only one oscillation of the field,” he said. “The critical point is the interplay and sync between oscillations. Even if each oscillator is weak, sync between them can induce a strong and very selective force.”
One of Koch’s collaborators, György Buszaki was fairly clear as far back as 2004 in terms of where he stood on this debate, highlighting various functions that the brain’s electromagnetic fields perform, including linking different areas of the brain together, facilitating synaptic changes, and creating and consolidating memory. So Buzsaki accepts that these fields have functional roles and are not like the sounds of a beating heart or a locomotive whistle.
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Pascal Fries, a well-known German neurophysiologist, also supports a functional role for the brain’s fields. In his work, he highlights the role of field synchronization across different parts of the brain in altering patterns of communication, and thus consciousness. He stresses that these dynamics exist over and above the “more rigid anatomical structure” of the brain.
Perhaps the most compelling recent research in favor of the functional role of electromagnetic fields can be found in a 2019 paper from Dominique Durand’s team at Case Western Reserve University. They examined slow electromagnetic field oscillations (less than 1 Hertz) in hippocampus tissue from decapitated mice. The researchers found that slow oscillations could trigger synaptic activity in neurons that were not connected by synapses. If they’re not connected synaptically, they can’t communicate through synaptic firing. Durand’s team wrote, “Results support the hypothesis that endogenous electric fields, previously thought to be too small to trigger neural activity, play a significant role in the self-propagation of slow periodic activity in the hippocampus.”
Durand was as surprised by their results as others were. He said, “It was a jaw-dropping moment, for us and for every scientist we told about this so far.”
Koch is, however, skeptical of these results, given their statistical validity and effect size. He told me: “Of course, at this point, no neuronal mechanisms can be definitely ruled out (including exotic macroscopic quantum effects), as long as they don’t violate the laws of physics.” Like most new scientific findings that challenge consensus views, other teams will have to replicate Durand’s results for others to find them convincing.
It’s far too early to claim that the brain’s electromagnetic fields are the primary seat of consciousness with much confidence. But philosophers and neuroscientists who have proposed electromagnetic field theories of consciousness, of which my own General Resonance Theory is one variety, are building up evidence. The interested reader should check out Douglas Fields’ new book, Electric Brain: How the New Science of Brainwaves Reads Minds, Tells Us How We Learn, and Helps Us Change for the Better, as an introduction to this line of work. It delves into this debate in great detail. “Brainwaves are key to consciousness,” he writes. “But the results thus far are correlations and don’t prove cause and effect.”
No doubt advances in our understanding of the brain’s anatomy, and its fields, will help philosophers and scientists get a better handle on how to ask the right questions for probing the nature of consciousness in all of its many forms.
Tam Hunt is a philosopher, a practicing lawyer, and writer. He is the author of two books on the philosophy of consciousness: Eco, Ego, Eros: Essays in Philosophy, Spirituality, and Science and Mind, World, God: Science and Spirit in the 21st Century.