How does a cat land on its feet?

A perfect example of science and fun! Ever wonder how a cat is able to flip over so quickly and ensure it lands on its feet? Some super slow-motion capture and some careful handling of cats (none harmed in the making of the video) provides a look:

Stem cells used to treat a brain disease

While this latest research is a proof of concept, it’s a pretty impressive and important one. Scientists started out putting stem cells into mouse brains that were genetically modified to produce less myelin, essentially an electrical insulator of neuronal connections, and thus have various cognitive and motor deficits (abstract). Similar problems plague people through various demyelination diseases of the central nervous system (CNS), like multiple sclerosis, or of the peripheral nervous system (PNS), like Guillain-BarrĂ© syndrome. New cell growth was detected in the mouse brains, with a great proportion of the new cells being oligodendrocytes which are the cells responsible for covering neuronal connections with myelin (in the CNS). Substantial additional myelination was also observed with no clear negative effects.

Following these results the scientists ran a case study (abstract) on 4 boys with the genetic disorder Pelizaeus-Merzbacher disease which produces defective oligodendrocytes. The scientists injected stems cells, along with immunosuppression drugs, into the boys and saw substantial improvement in myelination near the implantation sites with no apparent adverse effects. Future studies will involve more patients and hopefully will lead to treatments of a number of highly debilitating diseases.

For another review …

“The China Study” by T. Colin Campbell and Thomas M. Campbell II

Full Title: “The China Study: The Most Comprehensive Study of Nutrition Ever Conducted And the Startling Implications for Diet, Weight Loss, And Long-term Health”
First published in September 2001

While this book has had its critics, and while I am not fully convinced by every single one of Campbell’s arguments, the scientific knowledge presented and the perspectives on diet, nutrition, and the interaction with agribusiness, science, and government make for a compelling and worthwhile read. Moreover, while criticism on specific points may be valid, Campbell is open and honest about the fact that some of the evidence is only suggestive, but his argument is that when all of it (the strong, weak, and in between evidence) is brought together the clear conclusion is that a whole-foods, plant-based diet is the way to be healthy physically and mentally throughout life. This is a somewhat more strict and specific formulation of Michael Pollan’s “Eat food. Not too much. Mostly plants.” One major difference though is that Campbell suggests that you can actually eat plenty as long as it is healthy, as studies have shown that vegetarians generally consume more calories but are healthier (with regards to a host of particular diseases discussed in the …

PHD Comics: The Neurobiology of Writing

For a good laugh, or perhaps a sigh of recognition and resignation, see Jorge Cham’s take on the writing process of (I assume) a student.

Does this fit with your experience?

Literally see a fish brain in action!

For those not already familiar with the Janelia Farm Research Campus of the Howard Hughes Medical Institute, if you follow great and exciting advances in neuroscience you will hear about work out of them frequently. Nikita Vladimirov (first author) and colleagues, including Jeremy Freeman and Misha Ahrens, just published a methods paper in Nature Methods describing a method for viewing functional activity of individual neurons in the whole brain of a “fictively” behaving zebrafish. Zebrafish are transparent and scientists have mapped their genome, making them a particularly valuable model organism. This new method, which involves a sort of virtual reality (moving light bars simulating movement) for the fish, along with expression of a calcium indicator which fluoresces when the neuron is active, was used to produce a very cool video:

One of the big challenges here was to avoid any of the scanning light that causes the signaling molecule to fluoresce from hitting the fish’s retina. Their solution was to scan simultaneously with two beams from different directions and along different planes, cutting off the beams when they would otherwise hit the retina and disrupt behavior.

Check out another take on this work over at

Preview of “Automata”

When one ponders the possibilities of the future of robotics and “artificial” intelligence (perhaps more properly “synthetic intelligence” once we’ve actually got it figured out), one usually looks to hard science fiction books. Isaac Asimov in particular comes to mind.

A few movies have done an ok job, including the interesting but also very flawed “I, Robot” with Will Smith and Bridget Moynahan, and Terminator: Salvation…. Both were at least decent movies, but neither felt particularly realistic and both tried to pull on our emotions in fairly obvious ways that felt anything but organic… more

Spurious Correlations

There are many tricks one can do with statistics to make an argument, and true to the old saying many statistical reports are lies of one sort or another (more so in the political arena than in the scientific arena, but statistic are often tricky to understand so the problem is universal). However there is another sort of “lie” that we all need to be aware of, and that is the lie of the spurious correlation. Tyler Vigen has created a humorous but insightful website dedicated to this phenomenon.

We often say “correlation is not causation”, but sometimes two things can be correlated and have exactly nothing to do with one another. This can give rise to superstition, or, as Tyler points out in his video at the bottom, it can be an opportunity to act as scientists and consider whether or not there is a reasonable chance that a causal mechanisms exists for the correlation.

Radio Lab did a show related to these ideas called “Stochasticity”, addressing the phenomenon of amazing coincidences and whether they really are as amazing as they seem and what the chances really are. After all, it is the seemingly amazing events which …

“Dance of the Photons” by Anton Zeilinger

Full Title: “Dance of the Photons: From Einstein to Quantum Teleportation”

This book was substantially enlightening and yet amazingly frustrating at the same time. Zeilinger begins simply enough with the standard story of Alice and Bob (the physicists’ personification of observer A and B), but he turns them into curious undergraduates. They are the medium through which the reader discovers the quantum world after being given an experimental opportunity by their physics professor and his postdoctoral student. The ground is covered and recovered, sometimes providing useful insight and other times being overly pedantic and annoying. Some parts are so dumbed down it may seem insulting, and this also makes the story take a long time to get through. On the plus side you learn quite a bit about polarization, Bell’s inequality, and a number of other quantum topics.

A bit over half way through the book Zeilinger transitions away from Alice and Bob and toward even more recent experiments with quantum teleportation. Here still many parts are well explained and without too many rereads you should have a fair conception of what is going on. Unfortunately some claims are completely opaque and claims are made with no basis. That is not to …

“On Intelligence” by Jeff Hawkins

This book is surprisingly good in its ability to reach both the lay reader (for at least the first half) and the reader familiar with neuroscience. Articles since its publications provide much greater detail and are very useful for those interested in going deeper, but On Intelligence serves very well as an introduction to the concepts. The ideas expressed in On Intelligence are important both for scientific advancement and for philosophical consideration. While one could argue that perhaps there are other forms of intelligence or ways to produce intelligence, Hawkins does a good job in arguing what intelligence is in terms of mammalian brains and what the basic neocortical unit does. While Hawkins brings these ideas together in an orderly framework, he does give credit to the many neuroscientists responsible for the various components and underlying ideas that make it possible. These ideas as a whole until recently have not been sufficiently discussed in the neuroscience community in my opinion, and I believe they will aid (and in fact already have aided) greatly in advancing our understanding of the brain and creating real “artificial” intelligence that isn’t actually artificial at all.

The balance between addressing the expert and lay audiences did at …

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