Wondering if your caged hamster gets bored? It's highly likely if the critter has nothing to do all day.
Those are the findings of University of Guelph researchers in the first research study to empirically demonstrate boredom in confined animals. The study appears today in PLOS ONE, published by the Public Library of Science.
The study's authors hope the results encourage the development of better housing systems for captive animals.
"Ideas about how to assess animal boredom scientifically have been raised before, but this is really the first time that anyone's done it," said Rebecca Meagher, a U of G postdoctoral researcher and the study's lead author.
It's well-established that living in unchanging, inescapable environments induces boredom in humans, including prisoners who report that they are highly motivated to seek stimulation.
"But we cannot rely on verbal self-reports from non-humans, so motivation to obtain general stimulation must form the basis of any objective measure of boredom in animals," said Prof. Georgia Mason, who holds the Canada Research Chair in animal welfare in Guelph's Department of Animal and Poultry Science.
The researchers presented captive mink with stimuli ranging from appealing treats to neutral objects to undesirable things, such as leather gloves used to catch the animals.
Half of the animals in the study lived in small, bare cages. The other half lived in large "enriched" cages that were enhanced with water for wading, passageways for running, objects to chew and towers to climb.
The researchers found that animals in confined, empty spaces avidly seek stimulation, which is consistent with boredom. Those mink approached stimuli -- even normally frightening objects -- three times more quickly and investigated them for longer. These animals also ate more treats, even when given as much food as mink in enriched environments.
When they were not being tested, mink in empty cages spent much of their waking time lying down and idle. Among them, those that spent the most time awake but motionless showed the keenest interest in stimuli.
"We don't know whether mink or other animals truly feel bored in the same way that humans do," Meagher said. "We can't measure that type of subjective experience. But we can see that, when they have little to do, then just like many bored humans, they may look listless, and, if given the chance, eagerly seek any form of stimulation."
Guelph neuroscientist and psychology professor Mark Fenske, an expert in human cognition and emotion and recent co-author of a comprehensive review of boredom research, said the study is an important addition to the literature.
"Surprisingly little is known about boredom, even though it is associated with significant adverse consequences for health and well-being," he said.
"Being able to now study boredom in non-human animals is an important step in our efforts to understand its causes and effects and find ways to alleviate boredom-related problems across species."
Meagher and Mason hope the findings will prompt further research, including looking at whether intelligent animals such as primates and parrots are particularly prone to boredom in captivity, and why under-stimulation causes problems.