Showing posts from September, 2020

Book Review: The Neuroscience of Intelligence

A popular question on the question site Quora is “how do I increase my IQ/intelligence?”  There are a number of schemes advertised to do just that: exposure to Mozart, memory practice, video games, early childhood interventions, plus various pills, supplements, and nostrums.  Unfortunately, says Richard Haier, writing in his book, The Neuroscience of Intelligence , none of them appear to work. I have long been an IQ skeptic, with the core of my skepticism being based on the lack of identifiable neurobiological correlates of IQ.   Such correlates, based mainly on brain imaging studies that are of relatively recent availability, are the major theme of the book. So what are those neural correlates?   Many of them seem to be connected to communication and connection between the frontal and parietal regions of the brain.   Functional magnetic resonance imaging (fMRI) of the brain reveals the most active regions of the brain during task performance.   The brains of high IQ persons have

In the Beginning

And the  Lord  God formed man of the dust of the ground, and breathed into his nostrils the breath of life; and man became a living soul.  ............... Genesis 2:7, KJV Modern theories of the origin of life, call it clay.  Clay, it happens, can catalyze the formation of strands of RNA up to a few dozen bases long.  It can also catalyze the formation of lipid and protein vesicles which have some of the properties of cells.  Such vesicles can provide convenient reaction chambers for RNA molecules to form longer chains, possibly reproduce, and maybe even serve as templates for linking amino acids into simple proteins. Sound plausible?  Hey, don't blame me, it's Genesis.

Breathing Lessons

Once upon a time, two new animal body plans were invented  - OK, it was during the Triassic, 230 million years or so ago. They were, respectively, the prototypes of the mammals and the dinosaurs.  Because the Triassic was notoriously low on oxygen, with maybe half the concentration of today, breathing was tough, and lots of the less talented perished.  Mammals had an innovation, the diaphragm, which allowed walking and breathing at the same time, an advantage not enjoyed by lizards. Dinosaurs had another, a two cycle lung. The mammalian lung is a cul-de-sac.  Air comes in and leaves by the same path.  The dino lung, though, is a sort of two cycle lung that separates inhaled and exhaled air except at the ultimate intake and exit.  This lung, subsequently inherited by, among others, birds, is more efficient.  At 5000 feet, the bird lung is about twice as efficient as the mammalian version.  Given that during the Triassic and early Jurassic oxygen levels were more like those now found at

Hidden Agendas

I sometimes read a little Scott Aaronson.  He is obviously a bright and, I think, extremely sincere guy, but many of the questions he is interested in don't interest me that much - like a recent discussion of whether rational thinkers (or Bayesian agents with common priors) can honestly disagree.  That particular notion is not very interesting to me since I don't really believe humans can usefully be approximated by either Bayesian agents with common priors (or rational thinkers, for that matter.) Anyway, I wound up reading a post on Robin Hanson .  In it he vehemently argues that Robin Hanson is absolutely not insincere or possessed of a hidden agenda.  I found this amusing since in the same post he discusses a recent book of Hanson's whose theme is that much of human activity is not directed towards its ostensible end but rather consists of "signalling."  Which pretty much by definition is insincere behavior with a hidden agenda.

Heat Death

 The Permian-Triassic extinction was the granddaddy of all post Cambrian mass extinctions.  While the cause has been contentious, evidence has piled up in favor of Death by Greenhouse - a tremendous increase in global temperatures caused by very high levels of carbon dioxide, coupled with low levels of oxygen.  Plants and animals do not do well at high temperature, and high ocean temperatures can limit marine oxygen. Seen from our vantage point so long after, the Permian extinction was a repeat of what happened at the end of the Devonian, itself the first of what we now call greenhouse extinctions. Many more were destined to come at the end of the Triassic, multiple times in the Jurassic and Cretaceous, and ending with the last-known greenhouse extinction at the end of the Paleocene epoch, some 60 million years ago. But none were ever to be so great as the Permian event, or to unleash a more diverse assemblage of animals in the aftermath of extinction. Ward, Peter. A New History of Lif