Habits Of Rats Transferred By Chemicals At U-M

Monday, January 1, 1968

THE ANN ARBOR NEWS Page Seven

Habits Of Rats Transferred By Chemicals At U-M

(Special to The News)

NEW YORK—The rats and pokes around the box suddenly he raises up, his left front paw strikes a tiny bar. There’s a click and the animal quickly turns to the food cup and eats the dropped pellet.

Can this approach response be transferred from one rat to another by RNA injections to hasten learning? Is this just a chance activity?

University of Michigan psychologist James V. McConnell believes that rats can even lean to avoid flavored water, and this, too, can be transferred other rats.

Prof. McConnell, who first showed that memory can transferred from trained flat-worms to untrained worms RNA injections, described latest research at the 134th annual meeting of the American Association for the Advancement of Science Saturday.

Laboratory tests at the U-M Mental Health Research Institute indicate that "different types of habits can be transferred by different types of chemicals," he said. 

The researchers first trained rats to approach foods on certain signals. Then, extracting e ribonucleic acid (RNA) from the brains of these rats and injecting it into brains of untrained rats, the investigators found that the untrained rats learned faster.

RNA is a chemical, popularly regarded as the “memory molecule,” which in partnership with DNA directs or codes the patterns of heredity of all living organisms.

In just the past two to three months, scientists who previously had failed reported successful transfer results in a variety of different training activities, Dr. McConnell pointed out. 

The U-M research psychologist is currently conducting experiments which go a step further than the transfer of approach responses. “We are seeking to transfer conditioned avoidance responses as a more definite control study. Rats have an innate self-protection ability to avoid poisons or harmful foods. They test food in such minute quantities that if they become ill, they will avoid this food. We are giving rats saccharine-flavored water, then injecting them with chemicals that make them sick. They thus learn to avoid the flavored water." 

Dr. McConnell will transfer brain RNA from rats who learn j this avoidance response to untrained rats, and check their learning rates. If the avoidance response can be transferred, it is a rather good indication that memory can be transferred by injections of chemicals.

But do the animals really team a specific response, or, some scientists state, is the action of bar-pressing just the happenstance of general activity*

Another member of Dr. McCo-nell’s research team, National Institutes of Health fellow Dr. Arnold M. Golub, will report to 
AAAS on this question. His report was written with R. James A. Dyal, a National Science Foundation fellow at the University of California.

One thing is certain: The rats the U-M investigation that to press the bar for food make as many as 200 presses one hour.

To establish whether learning place, there is another group of rats (the controls) who get no food, only sensory stimulation.

When the hungry experimental rat is placed a box, a hungry control rat is placed in a second box. The equipment is set up so that when the experimental rat presses the bar, the click is heard also by the control rat. When the experimental animal enters the food cup to get his pellet, he breaks a photoelectric beam, causing a light to flash. The control rat also sees the light.

When both the experimental rat and the control rat are tested later, only the experimental rat has learned how to get the food. The click and the light have apparently taught the control rat nothing.

Dr. McConnell did his first search on memory transfer at the U-M in 1960, with his famous studies of cannibalistic planarians. Finding out that the tiny worms could learn to contract to avoid shock at the onset of a light, he ground up the trained worms and fed these to untrained worms. The untrained worms learned the contracting response faster than the control worms which were fed untrained worms. Later, RNA from trained worms was injected into untrained worms, causing them to learn faster.

A former doctoral student of Prof. McConnell, Allan Jacobson, reported in 1965 at UCLA that he achieved similar results with rats. McConnell repeated Jacobson’s work, successfully, and went on to do experiments showing the memory transfer effect in different training situations.

“We’re still at it,” said McConnell. “Where we go from here is anybody’s guess.”