(Lack of) Progress in neuroscience

Here is what I just posted to the epic thread on Connectionists:

The original complaint in this thread seems to be that the main problem of (computational) neuroscience is that people do not build upon the work of others enough. In physics, no one reads the original works of Newton or Einstein, etc., anymore. There is a set canon of knowledge that everyone learns from classes and textbooks. Often if you actually read the original works you’ll find that what the early greats actually did and believed differs from the current understanding.  I think it’s safe to say that computational neuroscience has not reached that level of maturity.  Unfortunately, it greatly impedes progress if everyone tries to redo and reinvent what has come before.

The big question is why is this the case. This is really a search problem. It could be true that one of the proposed approaches in this thread or some other existing idea is optimal but the opportunity cost to follow it is great. How do we know it is the right one?  It is safer to just follow the path we already know. We simply all don’t believe enough in any one idea for all of us to pursue it.  It takes a massive commitment to learn any one thing much less everything on John Weng’s list. I don’t know too many people who could be fully conversant in math, AI, cognitive science, neurobiology, and molecular biology.  There are only so many John Von Neumanns, Norbert Wieners or Terry Taos out there. The problem actually gets worse with more interest and funding because there will be even more people and ideas to choose from. This is a classic market failure where too many choices destroys liquidity and accurate pricing. My prediction is that we will continue to argue over these points until one or a small set of ideas finally wins out.  But who is to say that thirty years is a long time. There were almost two millennia between Ptolemy and Kepler. However, once the correct idea took hold it was practically a blink of an eye to get from Kepler to Maxwell.  However, physics is so much simpler than neuroscience. In fact, my definition of physics is the field of easily model-able things. Whether or not a similar revolution will ever take place in neuroscience remains to be seen.

Addendum:  Thanks to Labrigger for finding the link to the thread:

http://mailman.srv.cs.cmu.edu/pipermail/connectionists/2014-January/subject.html

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Brain discussion

There is an epic discussion on the Connectionist mailing list right now.  It started on Jan 23, when Juyang (John) Weng of Michigan State University criticized an announcement of the upcoming Workshop on Brain-like Computing that the workshop is really about neuron-like computing and there is a wide-gap between that and brain-like computing.  Another thing he seemed peeved about was that people in the field were not fully conversant in the literature, which is true.  People in neuroscience can be largely unaware of what people in robotics and cognitive science are doing and vice versa. The discussion really became lively when Jim Bower jumped in. It’s hard to summarize the entire thread but main themes include arguing about the worthiness of the big data approach to neuroscience, lamenting about the lack of progress for the past thirty years, and what we should be doing.

The non-cynical view

Read the 2014 Gates letter to get the non-cynical view of progress for the poor. I’m actually on the more hopeful side of this issue, surprisingly. The data (e.g. see Hans Rosling) clearly show that health is improving in developing nations. We may have also reached “peak child” in that there are more children alive today then there will ever be. Extreme poverty is being dramatically reduced. Foreign aid does seem to work.  Here’s Bill:

By almost any measure, the world is better than it has ever been. People are living longer, healthier lives. Many nations that were aid recipients are now self-sufficient. You might think that such striking progress would be widely celebrated, but in fact, Melinda and I are struck by how many people think the world is getting worse. The belief that the world can’t solve extreme poverty and disease isn’t just mistaken. It is harmful. That’s why in this year’s letter we take apart some of the myths that slow down the work. The next time you hear these myths, we hope you will do the same.
– Bill Gates

 

The Stephanie Event

You should read this article in Esquire about the advent of personalized cancer treatment for a heroic patient named Stephanie Lee.  Here is Steve Hsu’s blog post. The cost of sequencing is almost at the point where everyone can have their normal and tumor cells completely sequenced to look for mutations like Stephanie. The team at Mt.  Sinai Hospital in New York described in the article inserted some of the mutations into a fruit fly and then checked to see what drugs killed it. The Stephanie Event was the oncology board meeting at Sinai where the treatment for Stephanie Lee’s colon cancer, which had spread to the liver, was discussed. They decided on a standard protocol but would use the individualized therapy based on the fly experiments if the standard treatments failed.  The article was beautifully written, combining a compelling human story with science.

The myth of maladaptation

A fairly common presumption among biologists and adherents of paleo-diets is that since humans evolved on the African Savannah hundreds of thousands of years ago, we are not well adapted to the modern world. For example, Harvard biologist Daniel Lieberman has a new book out called “The Story of the Human Body” explaining through evolution why our bodies are the way they are. You can hear him speak about the book on Quirks and Quarks here. He talks about how our maladaptation to the modern world has led to widespread myopia, back pains, an obesity epidemic, and so forth.

This may all be true but the irony is that we as a species have never been more fit and adapted from an evolutionary point of view. In evolutionary theory, fitness is measured by the number of children or grandchildren we have. Thus, the faster a population grows the more fit and hence adapted to its environment it is. Since our population is growing the fastest it’s ever been (technically, we may have been fitter a few decades ago since our growth rate may actually be slowing slightly), we are the most fit we have ever been. In the developed world we certainly live longer and are healthier than we have ever been even when you account for the steep decline in infant death rates. It is true that heart disease and cancer has increased substantially but that is only because we (meaning the well-off in the developed world) no longer die young from infectious diseases, parasites, accidents, and violence.

One could claim that we are perfectly adapted to our modern world because we invented it. Those that live in warm houses are in better health than those  sitting in a damp cave. Those that get food at the local supermarket live longer than hunter-gatherers.  The average life expectancy of a sedentary individual is not different from an active person. One reason we have an obesity epidemic is that obesity isn’t very effective at killing people. An overweight or even obese person can live a long life.  So even though I type this peering through corrective eye wear while nursing a sore back, I can confidently say I am better adapted to my environment than my ancestors were thousands of years ago.