About

Terence Sanger is a child neurologist, medical researcher, electrical engineer, neuroscientist, professor, and writer

Who am I?

I am a child neurologist and electrical engineer, specializing in computational models of the brain: how it works, and why it breaks.  As a clinician, I specialize in childhood movement disorders such as dystonia, spasticity, tremor, chorea, and ataxia.  These are disorders that distort a child’s intended movement and can make it difficult or impossible for children to move or communicate as they want.  This type of movement disorder can occur in children who have cerebral palsy or other brain diseases.  As an electrical engineer, I use computers to analyze information about children’s brains and their movement, and to model how the brain works and how it breaks.  In particular, I use theory from Robotics and Machine Learning to understand why learning sometimes fails, and how that can lead to unintended or impossible movement in robots and children.  The goal is to use computer models of childhood movement disorders to design new technology and treatments to help children.

Poetry

A poem about Schroedinger’s Cat. Perhaps the only poem ever written on this topic:

Thinking about Language

Once a species has language, it wins. There is no going back. Language is the nuclear weapon of inter-species competition. Not only because language allows you to describe and invent things that don’t exist, but because language changes the very nature of evolution. “Evolution” just means that species change over time. The question is why? Charles Darwin’s theory in its simplest form suggests that random genetic variation creates lots of opportunities for new traits, and then through competition the animals with better traits out-survive their competition.

But before Darwin there were other theories. The theory of Lamarckian evolution is attributed to Sir Jean-Babtiste de Lamarck. Lamarck believed that acquired traits could be passed from one generation to the next (to be fair, other people had similar ideas, but I’m going to call this “Lamarckian” to keep things simple). If your dad becomes a bodybuilder, you will be stronger. If your mom becomes a university professor, you will be smarter. Darwin would say that you are stronger or smarter because your genes are similar to your dad’s and your mom’s. In other words, you and your dad are both strong, and you and your mom are both smart, but it’s not because of anything your parents did in their lifetime, it’s because of the genes they inherited and passed on to you, and it was all completely determined before any of you were born. Lamarck on the other hand, would say you are stronger or smarter because your dad worked hard and your mom studied hard.

Perhaps the Lamarckian mechanism is language. Before there was language, there was only Darwin. The only way to pass on things to your children was through genes. If you learn something or get stronger, your genes don’t change, so your children don’t get those traits. Lamarck’s theory faded out for lack of a mechanism and lack of scientific proof that acquired traits can be passed on. Until language. We now generally believe the knight’s theory does not explain the origin of species. Or even the origin of different physical traits within a species. We don’t have kidneys because our ancestors tried harder to regulate their blood sodium levels. We have kidneys because things without kidneys (or with worse functioning kidneys) did not survive as long as things that do have kidneys. But what about airplanes? We now have airplanes because our ancestors worked hard to have airplanes. And then they told us about it.

So Darwinian evolution is now in competition with Lamarckian evolution. Who will win? Will Darwin always design a better kidney? Maybe not, if scientists find a medicine to make kidneys work better or to fix ones that break or to eat foods that preserve your kidneys. What about better eyesight? Now we have glasses, telescopes, microscopes, radar, cataract surgery, and retinal lasers. What about strength? Now we have hydraulic machinery, electric motors, jet engines, and anabolic steroids (illegal for sports, but the point is we can do this if we want to). What about social behavior? We have that covered too. Even politics. Competition between species never stops, but Lamarckian evolution always wins on speed. If you learn something, you can pass it on immediately. It is an ability, not really a genetic trait, but does that matter to the woolly mammoth being chased by people with spears? Unfortunate mammoth is not going to evolve armor faster than humans can make sharper spears. Lamarck always wins in a competition with Darwin.

Darwinian evolution depends on “pressure”, in the sense that competition for resources (perhaps food) puts pressure on a species so that advantageous mutations are more likely to survive than disadvantageous mutations. But if we remove evolutionary pressure by making warmer coats so that we do not need to evolve fur, or stronger glasses so that we do not need to evolve better eyes, or gasoline engines so that we do not need to evolve faster running, then there is no pressure for survival of the genetically fittest. You just get a coat, or glasses, or a car, and get on with your life. Your children are not more likely to survive if they are faster runners, because they can just get in the car. So not only does Lamarck win over Darwin, Lamarck stops Darwin in his tracks.