Ex-Lab Chimps Show Remarkable Improvement After Treatment With Anti-Depressants

Illustration for article titled Ex-Lab Chimps Show Remarkable Improvement After Treatment With Anti-Depressants

One can only imagine the psychological and emotional states of research chimpanzees who have been poked, prodded, and confined for a good portion of their lives. No doubt, once relieved from the burdens of medical testing, many chimpanzees have a difficult time adapting to "normal" life. But as a recent small-scale experiment has shown, anti-depressants can help kick-start the road to recovery.


Indeed, many animals emerge from the labs depressed and traumatized. Many of them, after 15 to 20 years of confinement, have lost their capacity to play or relate to other chimps. Once liberated, many of them keep their distance from others, rock back and forth obsessively, pace back and forth, pull their own hair, and compulsively eat their own vomit. It's not a good scene.

Looking to do something about this, and in anticipation of the retirement of over 300 research chimps in the United States, Godelieve Kranendonk conducted a study on behalf of the AAP Rescue Centre For Exotic Animals in the Netherlands. Working with Martin Bruene, a professor of human psychiatric disorders at the University of Bochum, Germany, she prescribed a regimen of SSRIs (Selective Serotonin Reuptake Inhibitors) to five research chimps who had been used in medical experiments involving Hepatitus C.

Speaking to the BBC, Kranendonk shared the results: "Suddenly, [the chimps] woke up. It was as if they were zombies in their enclosures and now they are happy, playing with each other. They are chimps again — that was really nice to see." Their playfulness, she said, had been restored. More from BBC:

After six to eight weeks, the animals behaviour started improving. The abnormal behaviour declined and the chimps began to play together. After seven months, there was a vast difference.

Kenny responded best of all to the treatment. He is now the clown of the group, entertaining the others and initiating play.

Prof Bruene said that the results were "quite amazing".

He said: "I didn't expect this to work this well. These chimps have served as laboratory chimps for many, many years and suffered psychological trauma. I wouldn't expect a human [to recover] that has suffered a similar condition."

According to the researchers, the anti-depressants aren't meant as a longterm solution. Once the chimps "learn to be chimps again," they are weaned from the medication.

Interestingly, the effectiveness of SSRIs on chimps shows that they not only have neurological structures very much like our own, but that they also share similar emotional and psychological responses as well.


Image: Chimp Haven (which is where the 300+ chimps are set to retire).


Dr Emilio Lizardo

It is great that the chimps felt better. How do we know that they felt better because of the SSRI's and not just because they were living under better conditions or were getting more positive attention? Was there a control group?