New paper in The Lancet

The Lancet has just published a series of articles on obesity.  They can be found here.  I am an author on the third paper, which covers the work Kevin Hall and I have been working on for the past seven years.  There was a press conference in London yesterday that Kevin attended and there is a symposium today.  The announcement has since been picked up in the popular press.  Here are some samples:  Science Daily, Mirror, The Australian, and The Chart at CNN.



Genetic basis of intelligence

University of Oregon physicist Steve Hsu has just launched an initiative with BGI to study the genetic basis of intelligence.  See here for a summary of the project.  They are presently recruiting participants to be genotyped so check out the website if you are interested.  I have agreed to serve as a consultant on the project.  The reason for my involvement is because my recent research has involved estimating the heritability of various obesity and Type 2 diabetic traits from genomic data and these methods could be useful for the project.  I am also interested in the genetic and molecular basis of complex cognitive disorders like autism, schizophrenia and addiction.  I will make some expository posts on these topics in the near future.

I enter this project with full awareness that the topic of heritability and intelligence is a lightning rod for controversy.  I have even argued in the past that this is a topic that might be best left alone because any knowledge gained could be easily misused.  However, it is also clear that this project will happen with or without me and I decided that the potential benefits outweighed the costs.  When it comes to treating cognitive disorders like autism, schizophrenia and addiction, we still are in the dark ages and a large genome study of cognition could lead to potential new treatments.   BGI also has the will and wherewithal to devote large amounts of resources to this project.


Is tanning addictive?

This new article shows that exposure to UV light produces changes the blood flow to areas of the brain related to reward in ways that are similar to addictive substances.  I could see why this might be evolutionarily useful for people who evolved in northern latitudes to ensure that they get enough vitamin D during the sunny summer months to last through the dark winter months.  However, I would need to know what the biological mechanism is before I believe this completely.

Title: Activation of the mesostriatal reward pathway with exposure to ultraviolet radiation (UVR) vs. sham UVR in frequent tanners: a pilot study

Abstract: Frequent and excessive tanning persists despite a growing understanding of its associated morbidity and mortality, suggesting that ultraviolet radiation may impart rewarding effects beyond the assumed cosmetic benefits. To empirically measure putative centrally rewarding properties of ultraviolet radiation (UVR), we assessed the effects of a commercially available tanning bed upon regional cerebral blood flow (rCBF), a measure of brain activity, using single-photon emission computed tomography (SPECT). Seven frequent salon bed tanners were placed under a UVA/UVB tanning light during two sessions; one session with UVR and the other with filtered UVR (sham UVR). Session order was randomized and subjects were blinded to study order. During the UVR session, relative to sham UVR session, subjects demonstrated a relative increase in rCBF of the dorsal striatum, anterior insula and medial orbitofrontal cortex, brain regions associated with the experience of reward. These changes were accompanied by a decrease in the subjective desire to tan. These findings suggest that UVR may have centrally rewarding properties that encourage excessive tanning.

The remarkable Bob Milne

Radiolab is featuring a short podcast on pianist Bob Milne. Aside from being a remarkable musician and ragtime pianist, Milne also has the uncanny ability to listen to multiple pieces of music simultaneously. Neuroscientist Kerstin Bettermann gave Milne a test where he would have to keep in his mind four orchestral pieces starting at different times. She then started the recordings of the same pieces and ten or so minutes later, she would ask him where he was in each of the pieces. He was almost exactly in sync with each one. As a control she tried this on an experienced conductor who could keep in sync for only one piece. One of the dogmas of cognitive science is that we cannot really do multi-tasking but this is clearly a counter example. It would be extremely interesting to see if he could follow simultaneous conversations or watch simultaneous movies. Is this ability exclusive to music? Does having this ability incur some cost? Is there a trade-off? I think that mapping out the full capabilities of the human mind is very useful for understanding how the brain works.