NETWORK OPTIMIZATION IN THE BRAIN [I, 1991]: From C. elegans to Cerebral Cortex

Abstract

How well do "Save wire" concepts from combinatorial network optimization theory fit as models for brain anatomy? One result concerns ganglion placement in the nervous system of C. elegans: Our exhaustive searches indicate that the actual layout of the ganglia in the roundworm requires less total interconnecting wirelength than any of the 40 million other possible layouts -- a predictive success story. For the corresponding, but combinatorially intractable, question of interconnection wire- minimization in placement of the areas on the cerebral cortex sheet, we tested instead an "Adjacency Rule": If components a and b are interconnected, then they are contiguous. If cortical components are placed to minimize total interconnection costs, one would expect conformation to this rule; we found strong support for both macaque and cat visual cortex, as well as C. elegans ganglia. [ MH49867 9/91 3.0 ] (UMIACS-TR-2003-92)