The trope that the human brain didn’t evolve to understand advanced physics is often applied in popular science.
After all, early humans’ priorities were constricted to comprehending and contending with predatory threats, learning how to feed themselves and their group, seeking out conditions that were favorable to the functioning of their bodies, and deciding who might make a good candidate to produce offspring with. Wrapping their heads around the intricacies of something like physics would then be an unnecessary, metabolically expensive task with no real benefit to human survival and reproduction, right?
Sure, the laws of classical physics, which relate to Newtonian concepts like velocity and momentum, seem to make sense to us because they describe the behavior of objects in the world as we experience them. When Isaac Newton declared that an object will only change its motion if a force acts upon it, we found this easy to understand because it relates directly to our perception of how things move and behave in the world.
But some post-classical concepts introduced by modern physics — such as entanglement, dark matter and the multiverse — seem to be at odds with what our common sense tells us about the world. And we often explain the counter-intuitiveness of ideas like non-local particle dynamics, wave-particle duality and the potential of a near infinite number of possible realities by invoking that popular trope: These concepts seem to be outside the pay grade of our specialized cognitive machinery.
Do As the Experts Do
Thinking about this stuff hurts. Well, at least for most of us. Why? For a while now, neuroscientists have investigated how a number of concepts, from falling apples to dark matter, are represented in the neural substrates of the brain.
Using functional MRI, which tracks where blood is flowing in the brain, and other techniques, Robert Mason and his colleagues at Carnegie Mellon University’s Center for Cognitive Brain Imaging attempt to identify the neural activation patterns of abstract scientific concepts. And in particular, patterns associated with some of the more seemingly absurd ideas presented in post-classical physics.
When they asked trained physicists to think about specific physics concepts last year, the researchers found that “expert knowledge in physics has a neural trace that is measurable and is somewhat similar across experts,” Mason says. “We could identify concepts across individuals even when they were trained in different systems and had different first languages.”
There are some potential mind-boggling implications for what this research could mean in the context of education. “This might be a very science fiction idea, but we may be able to assess knowledge in students by comparing to the expert’s knowledge brain state because it is measurable and consistent across experts,” he adds.
Although these neural representations are consistent enough to be recognized across individuals, however, Mason stresses that the brain is a dynamic, context-dependent entity — and that there’s a lot of variation in how a brain may represent concepts over time and across different individuals.
“Every time we think of a concept, the brain will have some common trace that allows it to be identified in [functional] MRI in both individuals and across them, but there is likely also a response that may be context-dependent,” he says. “It is likely that even a simple concept does not have a single pattern of activity that is exactly the same every time it is encountered.”
While the number of participants in Mason’s study was relatively low (it's not easy recruiting expert physicists to participate in psychological studies), the data found is similar and consistent with a much larger set of investigations on the neurosemantics of concepts across different conceptual domains.
For instance, the nature of many post-classical concepts requires the consideration of alternative possible worlds, such as the multiverse concept that many comic book fans are familiar with. Regions of the brain that were associated with hypothetical or speculative reasoning in previous research played a significant role in the neural signatures of post-classical concepts that required this type of abstract thinking.
Additionally, post-classical concepts often require the unknown or non-observable to be brought into agreement with what’s already understood. This same process is often needed in the comprehension of an unfolding narrative; regions of the brain that activated when physicists thought about certain post-classical concepts in this study also activated when readers judged the coherence of a new story segment in a different one.
In a way, it seems as though the brain is reappropriating regions that may have been traditionally used to carry out more general conceptual tasks — with those original tasks sharing characteristics with newer, post-classical physics concepts.
“The way I think about it is that the brain has various regions specialized for different types of thought and perhaps with redundancies in various parts of the cortex,” Mason says. “It may be repurposing structures used for other tasks and thoughts, but it could also be true that some regions exist that can be tuned to newer thoughts as they emerge and become consistently used by the individual.”
Throughout history, our minds have accommodated abstract ideas in the realms of philosophy, morality, storytelling — where nuanced concepts couldn’t be reduced to simple visual representations and where we were faced with contradictions at every turn.
Perhaps our brains have had, for a while now, the tools to represent advanced concepts like those found in post-classical physics. Perhaps our characterization of the brain as not being adequate in its ability to encode for complex theories doesn’t give our brain the credit it deserves as a malleable, adaptive entity. It certainly gives us a lot to think about.