INFORMATION-PROCESSING AND INTRACELLULAR NEURAL (PROTEIN) NETWORKS - CONSIDERATIONS REGARDING THE DIFFUSION-BASED HYPOTHESIS OF BRAY

The possibility that the disposition of subsets of proteins within the cell can retain memory traces and may act therefore in a computationa l role has been advanced and more recently refined by Bray (Nature (19 95) 376, 307-312). The proposition is not without its merits but inevi tably has a number of associated difficulties, some of which are discu ssed in this article. These relate to the nature of the computational units envisaged (analog vs digital), their limitations in the number o f stable patterns they can accommodate, the reliance on diffusion at t he molecular level as the 'governing principle', and the complication of the turnover of proteins through degradative mechanisms. These issu es suggest that certain modifications of the original model are requir ed.