Mental Health Agency Forces Animals to Fight in Gladiator-Style Tests

Small animals are fighting for their lives in experiments funded by the National Institute of Mental Health (NIMH). Experimenters lock pairs of mice, rats, hamsters, and other animals in cages so one will beat up the other in gruesome gladiator-style tests. 😨🐭🐹 Guess how much taxpayer money has gone toward these “social defeat” experiments. 🤔 Almost $15 million—and they haven’t produced a single treatment for humans. 🤯 Why tf is an agency dedicated to mental health destroying the mental health of animals?

Inside ‘Fight Clubs’

In “social defeat” tests, two animals—one who’s small and passive and another who’s bigger and more aggressive—are locked in a cage together. Experimenters then watch as the more aggressive animal beats up the other one. 😰 This violent act can go on for up to 20 minutes or until the smaller animal gets hurt badly enough for the experimenters to end the test. Some of the victims die if they’re not separated from the larger animals in time. 😭

The smaller animals cry out for help, stop moving to avoid being attacked again, or roll into a submissive position—all signs of fear and distress. And they keep suffering long after the experiment has ended. They may endure anxiety, depression, weight loss, and an increase in heart rate, temperature, blood pressure, and stress hormones for several days. In some tests, experimenters even cut open animals’ skulls and insert electrodes into their brains. 😱

40+ Years in the ‘Fighting Ring’

If this experiment sounds straight-up archaic, that’s because it is. It started in the 1980s, when experimenters noticed that animals who experienced social defeat showed negative physical and behavioral symptoms.

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Today, experimenters force small animals into the territory of more aggressive or dominant ones to induce stress. They hope it will cause symptoms of anxiety, depression, autism, and post-traumatic stress like those found in humans—or increase the animals’ risk of drug addiction. 😡 Use of the test has skyrocketed over the past decade, and it showed up in 10 times as many published papers in 2020 as in 2010.

The NIMH Director’s Low Blow

NIMH’s director, Joshua Gordon, previously put his own twist on the tortuous test. In a 2018 tax-funded experiment, he rubbed male mouse urine on the tails and vaginas of months-old female mice. Then he dumped the females into cages with large, aggressive male mice and watched for up to 10 minutes as they were repeatedly assaulted. Once time was up, the victims stayed trapped in the cages with their attackers (separated only by dividers) for another 24 hours. 😢😢😢

The females suffered through this horror for 10 days—with a different attacker each day.

Throwing in the Towel

Besides being extremely cruel, social defeat tests have huuuge problems. 🙄 For starters, animals in these experiments can’t escape from their attackers—unlike how they may be able to in their natural habitats.

PETA-owned image for the mental health article from

Forcing animals to fight in artificial laboratory conditions can’t even begin to replicate the complexity of human mental health conditions. Humans who suffer from anxiety, depression, post-traumatic stress disorder, autism, substance use disorders, and other issues experience unique symptoms and reactions to treatments and therapies—none of which can be simulated in laboratory experiments on animals. 😒

Help Knock Out Cruelty

Published NIMH studies have found that other animals aren’t good models for human afflictions. 😑 Scientists around the world are already using advanced, animal-free tech to study human brain conditions without inflicting pain or suffering on animals.

NIMH has received more than $16 billion in taxpayer funds for various experiments over the past decade. 💰 Please urge the agency to stop wasting this money on cruel and pointless animal experiments and fund human-relevant research instead: 👏

And if you’re a U.S. resident, please take additional action for animals in laboratories by supporting PETA’s Research Modernization Deal, which gives a comprehensive strategy for replacing all experiments on animals with more effective, human-relevant, non-animal methods:

Text peta2 to 30933 for ways to help animals, tips on compassionate living, and more!

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