Elephants on Acid (9 page)

Researchers often choose unusual locations to stage their experiments. We have already encountered memory experiments conducted in an operating room, a zoo, and a bar. But the prize for the most unusual setting for research in this field goes to Duncan Godden and Alan Baddeley of the University of Stirling. They tested the memories of subjects who were submerged twenty-feet deep in the chill Atlantic waters off the coast of Scotland.

The year was 1975. Eight divers from the Scottish Sub-Aqua Club descended to the bottom of Oban Bay, where they sat anchored down by weights, holding in their hands a Formica board and pencil. Eight other divers, also dressed in scuba gear, remained on the beach. All participants then heard through their headsets a list of words. The list was read twice. The question Godden and Baddeley sought to answer was this: Would the words learned underwater be best recalled underwater?

This may not seem like a question of great practical value, except for those planning to take an exam in a swimming pool. But as often is the case with such things, there was more to it than met the eye. What Godden and Baddeley were really interested in was context dependency in memory. Is there a link between memory and place? For instance, if you learn a subject in a particular classroom, is it easier to recall that subject in the same classroom?

After hearing the list of words, four of the submerged divers ascended, and four of the divers on the beach dived into the water. All sixteen participants then wrote down as many of the words as they could remember. The results were clear. Those who remained in the same place, whether underwater or on land, scored higher than those who moved. Environment appeared to have a large impact on recall.

Could the effort of moving have disrupted attempts at memorization? To address this possibility, the experimenters ran a second test in which, in between hearing the word list and taking the test, the subjects on the beach briefly dived into the water and returned to the beach. The disruption had no significant effect on memorization.

Due to the Scottish climate, this research involved some hardship. Godden and Baddeley noted that “subjects began each session in roughly the same state, that is, wet and cold.” There was also risk. While underwater one diver almost got run over by an amphibious army truck that happened to be passing by. But it was worth it. The experiment was well received and is frequently cited as evidence of a same-context advantage in learning.

Nevertheless, recent studies have cast doubt on whether Godden and Baddeley’s results can be generalized to other contexts. A 2003 Utrecht University study repeated their experiment in a more down-to-earth setting—the university’s medical center. Sixty-three medical students were given lists of words and patient case descriptions to learn in both a clinical bedside setting and a classroom. No same-context
²³
advantage was observed. Of course, the Utrecht study did not require the medical students to wear full scuba gear. This may have played a role in the differing results.

A mother takes her child to the doctor to get his shots. As the doctor prepares the usual measles and tetanus injections, he inquires casually, “Would you be interested in any French or Spanish for Johnny?” The mother considers a second. “Yes, I think he should know French. Why don’t you give him a shot of that. Oh, and I noticed he was making some mistakes in his piano practice last week. Could you also give him a booster of piano?”

Might acquiring a new skill someday be as easy as going to a doctor’s office and getting an injection? It’s not likely, but between the 1950s and 1970s, there was a brief, heady period when many thought it was a real possibility. In 1959
Newsweek
declared, “It may be that in the schools of the future students will facilitate the ability to retain information with chemical injections.” In 1964 the
Saturday Evening Post
looked forward to a day when people would be able to “learn the piano by taking a pill, or to take calculus by injection.” The cause of this excitement was a series of unusual experiments involving, of all things, cannibalistic flatworms.

The experiments began in 1953 at the University of Texas, where James McConnell and Robert Thompson were students. They were interested in what was, at the time, a relatively new theory of memory—the synaptic theory, which posited that memories form when new synaptic connections are made between neurons in the brain. Fate was set in motion when the two decided to use flatworms to study this theory.

Flatworms, also known as planarians, are humble little creatures. They measure only half an inch to two inches in size. They have pointed heads, tiny eye spots, and slimy, tubelike bodies. There are millions of them around, lurking beneath rocks near ponds and rivers, but most humans never notice them. McConnell and Thompson singled them out as research subjects because flatworms are just about the simplest forms of life to have neurons and synapses. But flatworms don’t have many neurons, which, it was hoped, would simplify matters from a research perspective.

The big question was, could flatworms learn? If not, they would be useless as subjects of memory experiments. Most scientists assumed they couldn’t learn, but McConnell and Thompson set out to prove the prevailing wisdom about planarians wrong.

Literally working out of their kitchen sink at first, the two students designed a flatworm training device. It consisted of a shallow, water-filled trough into which they placed a single worm. Over the trough they positioned a pair of bright lights. They would turn on the lights for two or three seconds, and then give the worm a jolt of electricity, causing its body to scrunch up. They repeated this procedure over a hundred times until eventually the tiny creature scrunched up as soon as the lights went on, in anticipation of the shock. This hardly made the worm the intellectual equivalent of Einstein, but it did demonstrate the worm had learned something—to associate the light with the imminent arrival of a shock.

Rival researchers found the idea of trained flatworms odd, but believable. If the flatworm research had ended there it would be remembered today as a solid piece of scientific work. However, it didn’t end there. In 1956 McConnell moved to the University of Michigan, where he continued to study flatworms. His experiments there would briefly make the worms international celebrities and start magazines speculating about memory pills and injectable learning.

One of the interesting things about flatworms is that if you cut them in half, each half—the head and the tail—will regenerate a complete body in about two weeks. It’s an enviable skill. McConnell decided to see what would happen if he trained some worms and then cut them in half. Would each half, once regenerated, retain the knowledge of the original worm? He anticipated the head would, but doubted the tail’s abilities. After all, there’s no brain in the tail. But to his surprise, the tails did appear to retain learning. Or to be more specific, the tails relearned the scrunching trick far more quickly than naive planarians (i.e., planarians that had never been exposed to training), which implied the tails had some memory of what they had learned. In fact, the tails performed better than the heads.

The scientific community greeted these results with deep skepticism. What McConnell was claiming was somewhat like saying memories could be transferred from one person to another via a leg transplant. It just didn’t seem possible, and it completely contradicted the synaptic theory of learning.

However, McConnell felt sure his results were correct. He decided it was the synaptic theory that was wrong, and he developed a rival theory of memory based on his findings. According to his theory, memories were not formed by neurons making new connections between one another, but rather were encoded onto molecules inside cells. He speculated that this “memory molecule” might be ribonucleic acid (RNA), the biochemical cousin of DNA.

Again, the mainstream scientific community had a tough time swallowing McConnell’s theory, and not just because his claims were so extraordinary. Many felt he was too much of a clown to be taken seriously.

McConnell seemed to go out of his way to tweak the sensibilities of the scientific establishment. He loved making grand, far-reaching claims about his research to the media—claims that annoyed his rivals. As interest in flatworm studies spread and a small community of memory-transfer investigators emerged, he started publishing a journal called the
Worm-Runner’s Digest
, to serve as a clearinghouse for the latest research, but it was hardly a typical journal. Instead, imagine a combination of
Mad Magazine
and the
Journal of Neuroscience
. The cover sported a two-headed flatworm coat of arms. Inside, serious articles rubbed shoulders with satire, comic verse, and cartoons. Under pressure from his contributors, McConnell eventually changed the format so that the serious content occupied the first half (which he renamed the
Journal of Biological Psychology
), and the humorous stuff—printed upside down—the second half. Which, in a way, made the journal even weirder. One had to flip it around to read the entire thing.

And yet, once again, had McConnell stopped there, his worm studies would still be remembered as intriguing (though unorthodox) work. But he didn’t stop, and it was his next experiment that not only made him famous, but also convinced his critics that he had traveled irrevocably into the land of woo-woo.

McConnell wanted to test his RNA hypothesis. He imagined the best way to do so would be to extract RNA from a trained worm, inject it into a naive worm, and then observe whether memory had been transferred. But he had no good way of extracting pure RNA from a worm. So, taking advantage of a second interesting thing about flatworms—that they happen to be cannibalistic—he settled on a far cruder method. McConnell simply chopped up a trained worm and fed it to a naive worm. He wrote:

Once the cannibals had had several meals of “educated” tissue, they were given their first conditioning sessions. To our great surprise (and pleasure), from their very first trials onward the cannibals showed significant evidence that they had somehow “ingested” part of the training along with the trained tissue . . . Somehow, in a fashion still not clear to us, some part of the learning process seems to be transferable from one flatworm to another via ingestion.

Whereas his previous work had been met with polite skepticism, these new claims evoked howls of disbelief. The general reaction of the research community—apart from McConnell’s small band of fellow memory-transfer enthusiasts—was something along the lines of, “You’ve got to be kidding!” It was like suggesting someone could acquire all of Einstein’s knowledge by eating his brain. Of course, McConnell was quick to point out that though RNA could survive a journey through a flatworm’s simple digestive system, it wouldn’t last long in the harsh, acidic environment of a human stomach—meaning that, even if his hypothesis was correct, RNA transfer wouldn’t work in humans via ingestion. However, the media overlooked this point and happily fantasized about a coming age of edible memory.

The debate over the biochemical transfer of memory dragged on for years. Many labs investigated the phenomenon. Some got positive results and supported McConnell’s hypothesis, but far more got negative results. Critics suggested the positive results were caused by experimental bias—the researchers were seeing what they wanted to see by misinterpreting the behavior of the flatworms. Supporters upped the ante by claiming to have found evidence of memory transfer in mammals such as rats. Critics fired back with a letter to the journal
Science
, in which twenty-three different researchers stated they had found no evidence that biochemical memory transfer worked in rats. Defenders of the theory insisted the critics had conducted poorly designed experiments.

However, with each round of the battle the supporters of memory transfer grew weaker. Funding began to dry up. The broader scientific community lost interest and turned its attention elsewhere. The memory-transfer theory was dying by attrition. At last even McConnell moved on to other things, leaving one lone enthusiast, a Baylor College of Medicine researcher named Georges Ungar, to fight the battle.

Ungar was convinced he had found evidence of memory transfer in rats. He had trained rats to fear the dark, then ground up their brains and injected extracts into the brains of untrained rats, who subsequently seemed to show a similar fear of the dark. To satisfy his critics, he decided to isolate what he believed to be the memory molecule from the brains of these rats in quantities suitable for widespread analysis. But training thousands of rats and grinding up their brains was a costly, labor-intensive procedure. He soon realized this was impractical. He needed an animal that could be more cheaply trained and dissected in mass quantities, and so he hit upon the idea of using the goldfish. Ungar announced a plan to
²⁴
train thirty thousand goldfish to fear colored lights. He would then decapitate the fish and remove their brains, creating a two-pound stockpile of the memory substance. Unfortunately, Ungar’s old age and death prevented the fulfillment of his scheme. For this, the goldfish were thankful.

With the death of Ungar, memory transfer lost its last great champion. And though the debate over biochemical transfer of memory went on for almost two decades, today you’re unlikely to find it mentioned in many textbooks. It’s as though it never happened, gone from the collective memory of science like a case of mild indigestion that caused brief discomfort, and was soon forgotten.

Mary C. checked into a clinic complaining of menopause-related anxiety. She probably imagined a few weeks of rest and relaxation awaited her, perhaps some psychological counseling. She couldn’t have anticipated what actually lay in store. First came the massive doses of LSD. Next was the intensive electroshock therapy. Soon she had no memory of her past. She didn’t even know her own name. She stumbled blindly through the hallways of the clinic, drooling and incontinent. But there was more to come—thirty-five days locked inside a sensory-deprivation chamber, topped off by three months of drugged sleep as a tape-recorded voice spoke the same phrases over and over from speakers inside her pillow:
People like you and need you. You have confidence in yourself.