Live Brains in the Lab

The recipe has long been a staple of science fiction: learn how to keep monkey brains alive after the monkeys die, then try the technique with humans. But whatever the profits of the fictional feat, such achievements would be even more rewarding to the real scientist. Now, at Cleveland Metropolitan General Hospital, researchers have taken the first long step: they have learned to keep isolated monkey brains alive.

A team led by Dr. Robert J. White takes a brain, which is about as big as a man's fist, out of a rhesus monkey's skull, retains only small bits of bone to serve as supports, and suspends the brain in an apparatus of tubes and rods. Its blood vessels are hitched to a small heart-lung machine, and fresh blood is supplied from a monkey blood bank. Delicate needles stuck in its surface al low an electroencephalograph to measure the electrical activity by which all brains do their work.

Dr. White's monkey brains sometimes stay alive for as long as 18 hours. When they finally die, it is usually because of waste products accumulating in the blood. Soon Dr. White hopes to use an artificial kidney to clean up the blood and lengthen the brains' survival time.

Sounds & Sights. While alive, the brains' EEG charts show a continuous flow of electrical signals, and Dr. White can communicate with them. When he rings a bell near the stump of a brain's auditory nerve, he gets an electrical reaction. When a needle carrying weak electric current touches the stump of the optic nerve, the visual part of the brain responds.

This activity indicates that the brain is functioning on a high level, reacting to signals that seem to come from its lost ears and eyes. But Dr. White is not sure whether the brain is asleep or awake. Does the brain believe it is still alive and in the original monkey? Is it frightened by loud sounds and bright flashes of light? Does it send desperate escape orders to nonexistent limbs?

Rewards in Death. No attempts have been made so far to find out whether the isolated brain functions logically, sizing up a situation on the evidence of its sense nerves, consulting its memory and giving appropriate orders to its muscle nerves. Such experiments might be made by using food rewards to train a living monkey to perform a simple action, such as reaching an arm forward when it hears a set number of familiar sounds.

When the monkey is fully trained, its brain would be isolated, and the sound signal given to its auditory nerve. If electrical signals appear in nerves that formerly led to arm muscles, this will mean that the brain's memories of past rewards are making it try to reach for food with an arm that no longer exists.

Still far in the future is another favorite idea of science fiction: using the isolated brains as cheap, efficient computers to do routine jobs. But if still living human brains ever become available, Dr. White's monkey techniques would probably keep them alive, and there might be jobs for them to do.

This file is automatically generated by a robot program, so reader's discretion is required.