Neural Darwinism – An Idea Reborn?

Years ago, I read a book by neuroscientist William H. Calvin, called How Brains Think. In it, he outlines a theory in which consciousness emerges through a myriad of super-fast ‘microevolutionary processes’ inside of our brains. Put simply, every thought you have and decision that you make is the result of a ultra-quick competition among a vast ‘population’ of candidate ideas. This theory is known as Neural Darwinism, and has been put forward as early as 1978.

This idea seemed fascinating to me. It provided a lot of answers to questions that I had about my own creative process, and also seemed to suggest that we could make ourselves better thinkers by providing the most suitable mental environments for ideas to evolve within. I’ve written about some of these ideas in previous posts on this blog. Like the best theories, it also seemed to have a certain elegance to it – it makes sense that one of the most powerful optimization mechanisms known – evolution – would be at work inside of our brains.

Unfortunately, there was a problem. In order for any kind of true evolution to occur in the brain, there needed to be some mechanism for replication. The mind didn’t seem to operate this way – from what we knew, ideas (or neural patterns) weren’t copied. Evolution won’t work, if the finches can’t lay eggs. It seemed like an interesting theory might be dead in the water.

A week ago, though, a research team from Hungary and the UK posted a paper titled ‘The Neuronal Replicator Hypothesis‘ which suggests that replication of neuronal patterns can (and does) occur within the brain using known neurophysiological processes. This would mean that, true to the ideas of Neural Darwinism, evolution could indeed play a role in cognition and consciousness. Furthermore, the paper also suggests that in combination with another known neural mechanism, Hebbian learning, this brain-based evolutionary process could be more powerful than the traditional Darwinist model.

This new development is exciting. Not only does it revive a once-promising theory, it also adds to it – perhaps giving us a workable model of how complex things like consciousness and creativity might arise. A better understanding of these processes is valuable not only at a scientific level, but also for anyone involved in creative endeavors. In the long run, it may be possible to actively ‘optimize’ our thinking processes – to have better ideas, to solve bigger problems – and be more creative.

2 thoughts on “Neural Darwinism – An Idea Reborn?”

  1. I don’t share your enthusiasm, though I’m too stingy with my dollars to fund the same research twice by paying for an article that has already been funded by the taxpayer.

    So now that I’m comfortable in my armchair, allow me to ask: how can neural circuits calculate fitness in a local way without solving the problems they are meant to be evolving solutions to in the first place? Usually the rest of the world handles that part.

    In fact, that was a similar problem with the famous “backpropogation” algorithm for training neural networks — while possesing of many elegant mathematical properties that allow computers to efficiently train neural nets to solve practical problems, it seems clear that the brain cannot use back propogation in practice because it is not a local algorithm, and so its importance to theoretical neuroscience is minimal.

    For an example of theoretical neuroscience having IMHO some good contact with reality, check out this fascinating talk on the interdisciplinary mongrel known as “neural field theory” that elegantly explains cave paintings and acid trips using ideas from particle physics:

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