The surprising rat park experiment

The rat park experiment is one of the most suggestive on the topic of addictions. Let’s say first that rats have been animals frequently used to perform “psychological experiments.” This is due to the enormous genetic similarity they have with humans. 95% of the genome of mice and humans is the same.

However, the use of rats for research It is always done under controlled conditions. That is, in laboratories. Most animals subjected to experiments remain isolated in cages, with hardly any contact with the outside world. This is, of course, an unnatural condition for animals of this species.

In the 1960s, rats were used to carry out some studies on addictions.. The so-called “Skinner boxes” were also used. These are designed with electrical devices that reward, with food, or punish, using electric current.

This scheme allowed a study of behavior, at least from the point of view of behavioral psychologists. The rat park experiment was a break with that paradigm. Let’s look at the topic in more detail.

The addicted rats

What behaviorists did in the 1960s was introduce rats to a delivery device through surgery. Then, as was customary, they were isolated in Skinner boxes, that is, in individual cages. After They were taught to press a lever inside the cage. When they did this, they self-administered a substance: psychoactive drugs.

In almost all cases, heroin was used, one of the most addictive drugs that exists. The point was that every time the rats moved the lever, they immediately received a small dose of drugs. The researchers noted that Some of them, under certain circumstances, or at certain times, repeatedly pressed the lever until they consumed high amounts of psychoactive..

Some of the rats even went so far as to forget to eat or drink water. What they did not forget was the self-supply of heroin. Therefore, several died during the experiment. The researchers concluded, by analogy, that if people had access to that type of drugs they would suffer the same fate as rats.

It was then that Professor Bruce Alexander appeared on the scene, with a group of researchers from Simon Fraser University, from Canada. It was they who proposed the rat park experiment.

The rat park experiment

Professor Bruce Alexander thought that the isolation of rats did not allow objective conclusions to be drawn. All the rats used were albino, descendants of Norwegian rats. It is a sociable, curious and intelligent species. Being in a cage was not his natural way of living. Based on that reflection, the idea of ​​doing the rat park experiment was born.

What Alexander wondered was whether the free rats would also act in the same way that the caged rats had done. Was there an innate tendency toward addiction? When they used drugs, the only possible fate was for them to immerse themselves in them until they died?

To answer these questions, Alexander began the rat park experiment in 1977. What his research team did was take two groups of animals. Some would be in the classic laboratory cages, isolated from each other. For the other group, however, a very large area was built, 200 times larger than a cage. This space simulated a park with trees and nature.

The interesting results

Because the site was so similar to a park, the research was called the rat park experiment. To complement it, the researchers brought other rats from the outside world to interact with the ones they were captive. The point is that Both the rats in the cages and those in the park had access to doses of morphine.

The researchers gave the rats the option of drinking two liquids. One of them contained morphine and the other did not.. They camouflaged the bitter taste of morphine with a sugary solution. After a few days, the caged rats began to prefer the liquid containing morphine. Those from the rat park also drank, but several days later.

The caged rats consumed 19 times more morphine than the free rats. The latter seemed to realize the benefits of not using the drug and were reluctant to do so., even if they had already tried it. Alexander and his team introduced variations, addicting several rats from both groups, but the pattern remained basically the same.

The rat park experiment demonstrated that social isolation was a determining factor for continued drug use. In turn, the company and freedom of the park significantly reduced the desire to consume. And when this occurred, the affected specimens did everything possible to return to their normal state, even enduring the withdrawal syndrome.

You might be interested…