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Theodore Holmes Bullock

Publications and source records attributed to Theodore Holmes Bullock.

3 recordsLinked to original sources
PubMed2006

How do brains evolve complexity? An essay.

A case can be made for the proposition that the most neglected aspect of biology is the evolution of complexity and for the assertion that the evolution of complex nervous systems--in short, of the brain--is an outstanding fact, manifesting a span of difference in grade of complexity from the simplest exemplars to the most advanced far greater than any other systems known except systems made up of many brains. The aim of this essay is not to make this case, which I take to be self-evident but to point out how little studied are the specifics defining the grades of complexity, in other words, the consequences of neural evolution. A major step in opening this field of study would be to recognize some way of measuring complexity, relevant to animal biology.

Animals↗
PubMed2003

Have brain dynamics evolved? Should we look for unique dynamics in the sapient species?

Ongoing "spontaneous" electrical field potentials of assemblies of neurons in the brains of diverse animal groups differ widely in character and amplitude without obvious explanation. There may be correlates with other measures of brain complexity, such as histological differentiation, but so far there are no known differences between the EEGs of humans and other mammals or between mammals and reptiles, amphibians or fish, apart from amplitude. The proposition is defended that further search for descriptors or statistical, probably nonlinear features of the time series will reveal consistent differences, meaning that we have so far missed major features of the natural history of EEGs, just as we have thus far relatively neglected the identification of features of the physiology of the brain relevant to its evolution of complexity through major grades of phyla, classes, and orders.

Animals↗