A University of Calgary researcher is looking at the complexities of the human mind in a unique way, by giving crystal meth to snails.
Dr. Kenneth Lukowiak has been investigating the links between memory formation and retention and certain chemicals for over a year and a half. While human neurology is too complex for experimentation at this stage, the dutch snail, with a simple nervous system, offers an attractively slimy substitute.
“The lab is interested in how we as humans learn and remember and forget,” said Lukowiak. “Because we know the complete neural circuit of the snails, we know where the memories are stored and we can begin to ask questions as to what goes on at the molecular level or the electro-physiological level.”
The experiments look at a behaviour in the snails known as aerial respiration to test their memory. Typically, snails breathe across their skin while under water, but if the oxygen levels in the water are low the snails come to the surface and open a breathing tube. Lukowiak and his research team motivate the snails to extend their tube by putting the snails in a low oxygen environment. Every time the animals come to the surface, they are gently hit with a little stick that causes the tube to close.
“The snails don’t like that, so they learn not to do that,” said Lukowiak. “We put them in the exact same situation again and ask, ‘Do they remember?’ Memory is simple. If you open [the airtube] 10 times on the first trial and 24 hours later you open three or four, you remembered. If you opened 10 on the first time and 10 on the second time, you didn’t remember. So it’s very, very simple behaviour.”
Lukowiak’s study collaborates with researchers in Washington State studying the process of addiction. Their theory was that people become addicted not only because of the pleasure experienced, but because addicts have a far better memory when high, causing the addicts to want to replicate the process. This led U of C researchers to question what would happen to the snails’ memory if they were given crystal meth.
“Initially I was quite skeptical,” said Lukowiak. “I thought it might block memory. I thought maybe it would just put the snail in an altered state so it wouldn’t care what was going on. But that wasn’t the case, the case was: memory was better.”
The experiment brought foreword a number of findings. If the snails were exposed to the drug, which was absorbed through the skin after being dissolved in water, 24 hours before being trained to not extend their breathing tube, they had better memory than if they weren’t given any. The results show Lukowiak that there is a link between certain chemicals and memory formation, which can be used to potentially help people to improve memory or forget.
“If you told me you had problems with memory I’d say, ‘Carry around a pad of paper’,” said Lukowiak. “If you told me you have problems forgetting, you can’t deal with that.”
According to Lukowiak, people suffering from post-traumatic stress disorder, for example, are a group that would benefit from the ability to forget traumatic experiences.
“People have tried all sorts of things to get people to forget and nothing really works well,” said Lukowiak.
The crystal meth experiments have also shown that the drug has the potential to bring about quicker memory loss. The snails receive extinction training (a way of blanketing over the learned behaviour of not extending their breathing tubes while under the water) after a dose of crystal meth, which the researchers found was effective in preventing the memories from returning.
“What it tells us is that maybe, if we want to get rid of a memory, one of the things we could do is to find something else that would improve memory and then give you extinction training,” said Lukowiak, who admits that finding such a substance is a problem in itself.
“There’s another problem too, the extinction training has to be context specific. So if I was teaching you something in this room, on an exam you would do much better if you took the test in this room,” he explained. “Quite often with addiction what happens is that someone becomes addicted to a drug, you put them in rehab, you put them in a nice place and give them good food. When they finish what do you do? You put them back on the street corner. Right away context specific memory goes back to, ‘I want it.’ That’s one of the problems with trying to break an addiction.”
Lukowiak will continue to explore other unknown effects of crystal meth on snails, as he says he “likes his snails too much to give up.”
Although the snails may be small, the secrets that Lukowiak hopes to unlock with them are not.
“The main goal of this lab is to figure out what memory is all about at the cellular level,” said Lukowiak. “I’d like to be able to say one day, ‘To form a memory in a cell, X, Y and Z has to happen. And because that happens then the properties of that neuron change.’ We’ve come close on some of it, but Mother Nature is pretty tricky and doesn’t give up her secrets very easily. Which is also good because it means that I still have a job.”