Book Rec

Can anyone recommend a good introductory book on global computation in the brain, aka. "Dynamic computation" or "Synchronization by oscillation"?

A complicated story of feedback loops piggybacking on environmental contingencies

"How we go from our genetic endowment to a fully developed human brain is a complicated story of feedback loops piggybacking on environmental contingencies, not a story of a developmental process unfolding in accordance with a 'genetic program.'"

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- David Buller and Valerie Harcastle, "Evolutionary Psychology, Meet Developmental Neurobiology: Against Promiscuous Modularity" Brain and Mind 1: 313-314.

Pleistocene Brains

We hear it often in our field that modern humans have Pleistocene brains, brains suitably adapted to life in the savannas of Africa where our ancestors lived for thousands of years. It was this period of stability that solidified our Pleistocene mind and all those fun modules. But is there any real evidence for this supposed Pleistocene mind/brain? I mean, any biological evidence other than just-so stories constructed based on clinical experiments with modern humans. I really would appreciate a point in the right direction. It seems patently false that we have Pleistocene brains, and also to fly in the face of evolutionary theory, which indicates our biology is constantly adapting.

Girls prefer pink? evolutionary or cultural causes

Lately a story stemming from an article in Current Biology has been circulating. This study allegedly demonstrates 1) that women prefer pink and 2) that there is an evolutionary explanation about this. Does that make you suspicous? Well it should.
This blog eloquently dissects it and seriously questions both conclusions. It is a good example of the abuse of evolutionary psychology and shows how easy it is to supply an evolutionary story to any experimental result. On closer scrutiny the experimental results do not support the evolutionary theory. Oh, and by the way the experimental results are, as shown in the blog, entirely explicable as having a cultural cause.
Instead of a study in evolutionary psychology it is a good study of a cultural effect in color preference.

This short article from Science shows that mind is conceptualized along two dimensions: experience (feelings) and agency, and experience is the most important.

Also see the supporting on-line material for more details.

Survival of the Sickest

I saw the author of the new book Survival of the Sickest interviewed on the Daily Show. It looks pretty interesting.

Writing as Ratchet

Deacon (1997) talks about Icon to Index to Symbol as hierarchically arranged. These systems, he argues, can be independent of the hardware. Recent work at UCSB and elsewhere has confirmed some of his argument with regard to the evolution of phonology out of primate visual systems. In this case, the hardware may evolve to make use of software in a kind of mutual ratcheting. That is, speech systems may be parasitic on visual systems (See Givon et al., The Evolution of Language out of Pre-Language). Studies in literacy often state that literacy isn't biologically instantiated, that it relies on more ancient mechanisms to do its work that evolved for different purposes. However, if we follow Deacon we can see this in a different light. In the same way that scholars before Deacon argued that biological changes had to precede "language", and he gave us a plausible argument for the reverse, we may say the same about written language. We see a similar process with literacy. This would lead us to substantially rethink what it means for something to be cognitive.

We find evidence for the ratcheting effect in the early story of writing from about 8000 to 3000 BCE as told by Denise Schmandt-Basseret. In the proto-stage human beings sculpted figurines representing various gods and animals for ritual purpose. In the next stage tokens of basic geometric shapes representing simple food staples were made out of baked clay. Next more complex tokens emerge that represent complex staples. These tokens come to be sealed in clay envelopes for accounting purposes, and so are connected to the rise of agricultural surpluses and cities. Since there is no way to tell what is in the envelope, in the next stage someone came up with the idea to embed tokens on the outside of the clay to tell what was inside and further a system of marks was developed for the same purpose. This facilitates a transition from three dimensional objects to two dimensional. Up to this point there is a one to one correspondence between an object and token, so for example, three jars of grain are represented by three tokens in or on the envelope. A sign represents the token inside the envelope, which in turn represents a commodity/staple. In the next stage clay tablets replace clay envelopes and a sign mark on the tablet is used to represent a token, marked either with a stylus or the corresponding token. The first recordings of numerals occur with these tablets. In other words, there is no longer a one to one correspondence. Here the sign represents a concept, not the particular object in question, and we move to greater degrees of abstraction. In the next stage, which she does not discuss, signs go from representing objects or concepts (pictures) to representing the sound of first syllable of the word for the concept (acrophonic principle) and eventually signs represent sounds.