Quotes "The Self-Assembling Brain"

From page 109 : "The code is a methaphor that works well for the genetic code or the rules of a cellular automaton. The code is a bad methaphor for the continously changing states of neurons as they run through their algorithmic programs. Imagine looking for a code in space and time for rule 110, iteration 1,234, position 820-870. To study the mechanism that led to that state, we look at the point before, the relation of how it happened, in all available detail. Is that useful? Well, it can be if leads to identification of the underlying rule. In the case of rule 110 automaton, the same rules applies evertwhere, so the instance reveals something general about the whole. This the hope of biological experiment as well. But what happens if the rule changes with every iteration, as discussed for transcription factor cascades? To describe changing rules of algorithmic growth for every instance in time and space and in different systems is not only a rather large endeavor, it also suffers from the same danger of undefined depth. It is a decription of the system, a series of bits of endpoint information, not a description of a code sufficient to create the system. The code is the "extremely small amount of information to be specified genetically ", as Willshaw an von der Malsburg put it (26) that is sufficient to encode the unfolding of information under the influence of time and energy. The self-assembling brain." (26). Willshaw, D. J., & Von Der Malsburg, C. (1976). How Patterned Neural Connections Can Be Set Up by Self-Organization. Proceedings of the Royal Society of London. Series B, Biological Sciences, 194(1117), 431–445. http://www.jstor.org/stable/77138

From page 234 : "The depth to which this context needs to be described is arbitrary, but can be meaningfully restricted based on its contribution to penetrance. A SNP (single nucleotide polymorphism) or mutation that reduce the penetrance in one out of 10,000 cases may not worth describing. Beside, if we go down that deep, the amount of context that requires description blow up the description. Yet, it is exactly these "details" at the genomic level that form the basis of evolutionary programming ate the level of neural circuit as assembly through selection of meaningful, heritable behavioral change."