Understanding Neurons: A Deep Dive Below the Bark

An important part of the human experience is striving for higher achievements and deeper understanding. In science, deeper understanding can have practical applications for health and ameliorating the impact of disease. Much like the discovery and reinvention we all experience across our lifespan, scientific discoveries are often inspired and driven by revisiting older assumptions, models, and conclusions. For this reason, a recent paper refining our understanding of the basic function of information transfer in neurons caught my eye.

Going beneath the bark

Although most of what I write here is about the forest (that is, a person in society) or the trees (which is to say ourselves and how we fit within society), I also delve into the bark of the nervous system and how that sustains behavior within a human and across society. Occasionally, I also delve into the next layer, which is deep under the bark and the domain of cellular neuroscience. This post goes deep into the bark and has made me think profoundly about implications for human health and behavior, and appreciate the iterative nature of science.

The most basic functional property of neurons is the capacity to transmit information from one cell to another largely by changes in electrical activity in the form of action potentials. Our understanding of this was pioneered by Hodgkin and Huxley in 1952, and their work on "cable theory" continues to inform basic cellular neuroscience. But there are some things that the initial work fails to explain, especially when trying to consider, understand, and relate cellular action potentials from individual neurons and macroscopic whole-brain network activity.

Brains are complicated, but are cells simple?

Although the functional properties of neurons can be understood at a base level as electrical cables, this concept fails to explain a lot of network behavior. This is where Vitaly L. Galinsky and Lawrence R. Frank, researchers at the University of California at San Diego, enter the fray. They wanted to derive a schema and mathematical model that could better explain and extend experimental observations. A key part of their model accounted for the way neurons actually function within the properties of brain tissue, something not factored in historically.

In their recent paper, published in Frontiers in Cellular Neuroscience, they point out that "[h]ighly non-linear systems in nature," like the human nervous system, "present a significant problem in data analysis and interpretation because they can produce a wide variety of seemingly disparate and unrelated coherent phenomena." This basically means that you can do the complex things you actually do because the cellular behavior underneath your human behaviors is wildly plastic and adaptable. The new model will be very useful for future investigations linking cellular, systems, and behavioral neuroscience.

Striving for a closer approximation of scientific truth is good for your health

These researchers highlight that the most important outcome of their work is bridging "the gap between the most elemental brain electrical unit—the neuron—and the large-scale, collective, synchronous behavior of the brain." Important applications for this work include direct methods "for relating neuronal activity to disease states characterized by demyelination, such as Multiple Sclerosis and myelin pathogenesis, including Alzheimer's Disease." And research like this exists because scientists continue to strive for the next closest approximation of truth.

Moving back out to the trees and the forest, the most important takeaway for me is that we must always strive for deeper understanding. Whether this understanding is at the microscopic level of cellular neuroscience or the level of human behavior, the point is the same. Stagnation and blind acceptance of past history are impediments to improvement.

This also got me thinking about one of my all-time favorite quotes about the nervous system, by physicist Emerson M. Pugh (1938): “If the brain were so simple we could understand it, we would be so simple we couldn't.” Despite the challenge, seeking a better understanding of human nervous system function and the natural world beyond is key to improving our place in the world.

(c) E. Paul Zehr (2025)