Archive for October, 2012


Adapting to the External World Internally

October 11, 2012

You had written about how diet rather than inactivity may lead to obesity, but heredity also plays a role, right?  Although genetics is one of the primary modes of hereditary information transfer, another very intriguing mechanism for hereditary information transfer is epigenetics.  As you may recall, when we were at Himanshu‘s wedding in Chicago, Ashwin was watching something on the Discovery Channel on how people conceived during famines have impaired glucose tolerance, raised blood pressure, and higher rates of obesity in adulthood.  Further if a grandfather went through a famine as a teenager, then a grandson would have higher mortality risk ratio.  Obesity seems to be linked to epigenetic phenomena.  Broadly speaking, it seems epigenetics are a quick way to pass on environmental adaptation to offspring.  Unlike genetics, an information theory of epigenetics seems to be lacking, though there has been some progress in understanding the epigenetic code.

I recently came across a paper entitled “Buyers’ Subjective Perceptions of Price” which appeared in the Journal of Marketing Research in 1973.  As is perhaps obvious, price influences buyers’ buying decisions, but a lot of behavioral experiments show that this influence is not at all straightforward.  In particular, it is really the perception of price that leads to behavior rather than the price itself.  One traditional view called odd pricing indicates prices just under a round number (e.g., 99) increase consumer sensitivity.  Although this strategy is discounted in the paper, it reviews several other techniques and phenomena such as perceptual price-quality relationships.  The most interesting part for me, however, was the invocation of the Weber-Fechner law from psychophysics for pricing and the ‘just noticeable difference’ experimental method from which it was originally derived.   As I think you know, together with John Sun et al., I have written a paper providing an ‘optimization approach to biology’ explanation for the Weber-Fechner law, basically arguing that our internal representation of external stimuli is well-matched to the environment.

So it seems adaptation to the natural world is central to the two most interesting informational systems in biology (at least to me): information transmission through heredity and information within nervous systems.