A dog’s love for a favorite ball or plush toy may be more than simple playful enthusiasm. New research suggests that for some canines, the intense focus and persistent desire for a toy can mirror behavioral addictions in humans, such as those to gambling or video games. This emerging area of study explores the psychological and biological underpinnings of why some dogs seem to become singularly focused on their toys, sometimes to the exclusion of other rewarding activities like eating or interacting with their owners.
A recent study published in the journal *Scientific Reports* provides the first empirical evidence that this “toy obsession,” often colloquially referred to as being a “ball junkie,” shares key characteristics with human behavioral addictions. Researchers investigated whether the intense, toy-focused behavior seen in some dogs meets the established criteria for addiction, including craving, loss of self-control, and a prioritization of the object of desire over other stimuli. The findings from this study, which involved 105 dogs, suggest that a subset of these animals do, in fact, exhibit these addictive-like behaviors, making dogs the only known non-human species to develop such traits naturally.
Observing Addictive-Like Behaviors
To determine if a dog’s intense interest in a toy crossed the line from healthy play into something more akin to addiction, researchers designed a series of tests to measure the animals’ reactions to various scenarios. The study, led by Alja Mazzini from the University of Bern in Switzerland, recruited 105 dogs described by their owners as highly motivated by toys. These dogs were placed in a room with their owner and a researcher and allowed to choose their preferred toy from a selection of three. The most popular choices were balls, selected by 45 of the dogs, followed by plush toys, chosen by 39.
The core of the research involved observing the dogs’ behavior in a series of 14 subtests. These were designed to assess key indicators of behavioral addiction, such as craving and salience. For instance, researchers would place the dog’s favorite toy in a sealed box or on a high shelf, making it inaccessible. They then introduced other rewarding options, including a food puzzle or the opportunity for social interaction with their owner. The researchers found that some dogs remained fixated on the out-of-reach toy, ignoring both the food and their owners’ attempts to engage them in play.
Signs of Obsession
The study identified several specific behaviors that pointed toward an addictive-like tendency. These included trembling, whining, lip licking, and intense focus when the toy was present but inaccessible. A dog was considered to show craving if it focused on the toy more than 50% of the time, even with other distractions available. Lack of self-control was another key indicator, observed when dogs would lunge at the toy before it was even released by the experimenter. In some of the more extreme cases, dogs exhibited destructive behavior in their attempts to get to the toy; two of the dogs in the study managed to destroy the box that their toy was hidden in.
Ultimately, the researchers concluded that 33 of the 105 dogs in the study displayed these addictive-like behaviors. These dogs persistently tried to access their toys when they were unavailable and did not calm down even 15 minutes after the toys had been removed. “What characterises a dog with a high tendency for addictive-like behaviour is that they seem to attribute extreme salience to their toys,” said Stefanie Riemer, a behavioral biologist at the Messerli Research Institute in Austria and a co-author of the study. She added that these dogs “exhibit craving for them even at the expense of other rewards or interaction with their owner.”
Parallels with Human Psychology
The concept of behavioral addiction in humans is well-established, with activities like gambling, gaming, and smartphone use recognized as having the potential to become compulsive. The researchers in the dog toy study drew directly from the criteria used to identify these human addictions. “The term ‘ball junkie’ is commonly used in the dog training world, the term implying addiction, but it has never been assessed whether addiction criteria may indeed apply to dogs,” said Professor Riemer. This study aimed to move beyond anecdotal observations and apply a scientific framework to the phenomenon.
One of the most interesting parallels, according to the researchers, is that not all individuals who engage in a potentially addictive activity will develop an addiction. “While the majority of dogs enjoy playing with toys, only a few develop an excessive fixation on them,” Mazzini stated. This mirrors the human experience, where many people can gamble or play video games without negative consequences, while a smaller number develop a compulsive need to continue the behavior. This study suggests that dogs may serve as a natural model for understanding the psychological mechanisms that underlie behavioral addictions across different species.
Biological and Breed Considerations
While the study did not delve into the specific neurological mechanisms at play, the observed behaviors suggest a strong biological drive. For some dogs, the act of chasing and retrieving a toy may tap into their innate predatory instincts. Breeds that have been historically bred for hunting and retrieving may be more prone to this kind of intense focus, as the toy can become a substitute for prey. The repetitive nature of fetch can be incredibly rewarding for these dogs, potentially leading to a compulsive need to engage in the activity.
Another factor may be the dog’s individual temperament and energy levels. Some breeds are simply more high-energy and may develop obsessive behaviors as an outlet if they are not sufficiently stimulated in other ways. The study itself included a variety of breeds, such as retrievers and terriers, which are known for their high motivation and drive. However, the researchers did not find a significant difference in mood between the “addicted” dogs and the other toy-motivated dogs when they were allowed to play, suggesting the issue is more about the craving and compulsion than the enjoyment of the activity itself.
Hormonal and Instinctual Drives
Beyond breed-specific traits, other instinctual behaviors could contribute to toy obsession. In some cases, particularly with female dogs, a toy may become a substitute for a puppy. This “mothering” behavior, which can include carrying the toy everywhere and protecting it, is driven by strong nurturing instincts, even in spayed females. For other dogs, the simple act of chewing on a toy can be a self-soothing behavior that helps to relieve anxiety or, in the case of puppies, the discomfort of teething. If a toy has the owner’s scent on it, it can be especially comforting, reinforcing the dog’s attachment to the object.
Implications for Dog Owners
The findings of this study do not suggest that owners should take away their dogs’ toys. For most dogs, playing with toys is a healthy and enriching activity. However, for the subset of dogs that show signs of obsessive behavior, a more mindful approach to play may be beneficial. Professor Riemer suggests focusing on cooperative play, such as tug-of-war or search games, so that the dog is not solely focused on chasing. “I wouldn’t say that you should never play with a ball with your dog, use it wisely,” she advises.
It is important for owners to recognize the difference between a high level of motivation and a potential behavioral problem. If a dog is consistently choosing a toy over food, ignoring its owner, or showing signs of distress when the toy is not available, it may be time to consult with a veterinarian or a behavioral specialist. In many cases, ensuring the dog has a variety of outlets for its energy and is engaged in different types of activities can help to prevent a healthy love of play from turning into an unhealthy obsession.