The analogies and differences between biological and artificial intelligence are today an object of discussion, controversy and working hypotheses. The search for analogies is based on the ways in which information is first recorded and then processed, generalised and retrieved. "Simplified" models of the nervous system have been put forward in order to explain these problems on the neurophysiological level. These may take the form of the nervous system of an invertebrate such as a worm or a snail, the circuitry of the spinal cord, complete with its excitatory and inhibitory components or, at a level of increasing complexity, the set of palaeoencephalic structures which modulate the "intelligent" behaviour of a species (the so-called "instincts") or, in the obvious case of the cerebral cortex, whose columnar arrangement makes it a powerful information analyser and processor.