The prize for medicine or physiology, given to Dr. Arvid Carlsson, Dr. Paul Greengard and Dr. Eric Kandel, is a reminder that the commerce in ideas flows both ways. The researchers, each in his own manner, have clarified how data circulate inside the brain. Molecules called neurotransmitters ferry signals from neuron to neuron, the information processors of the nervous system. There are obvious differences between electronic and biological circuitry. Computer chips communicate through simple metal wires.
Neurons send their molecular data streams across complex junctions called synapses.
And the language of the brain seems to be more complex than the simple binary chattering of computerese. But viewed at the most abstract level, both brains and computers operate the same way, by translating phenomena sounds, images and so forth into a code that can be stored and manipulated, giving both creature and their creations a firmer grip on the world. Dr. Kandel has drawn an especially vivid link between the nervous system and electronic circuitry. In classic experiments he showed how learning causes changes in the neurological wiring of a sea slug called Aplysia, whose nervous system is so simple that experimenting with it is like tinkering with an old radio. Training the creature to react vigorously to a stimulus, like an annoying squirt of water, causes an increase in the flow of neurotransmitters biochemical information across certain synapses, a tweaking of the neurological volume controls.