Anxious Dogs’ Brains Are Wired Differently

Does your dog start whining, barking, shivering, and get agitated the second you step outdoors? Or perhaps, your dog constantly seeks your attention, stares at you intently, and chews on your shoes and other items? According to a new study published in the journal PLOS One, researchers found that dogs with anxiety have differently wired brains compared to dogs who do not have anxiety.

More specifically, the team observed that dogs diagnosed with anxiety have abnormalities in their brain’s functional neural networks. Through fMRI scans, they found that the connections between these dogs’ amygdala and other parts of the brain’s “anxiety circuit” — particularly the hippocampus — were stronger in anxious dogs than their non-anxious counterparts. Located in the temporal lobe, the hippocampus plays a crucial role in learning and memory. Previous studies have shown that the hippocampus can get affected in several psychiatric and neurological disorders.

“The prevalence of anxiety disorders among dogs is high and the most encountered behavioral disorder in daily practice. Moreover, they form a serious welfare problem not only for the well-being of the individual, but they also compromise the relationship with the owner leading to abandonment, rehoming, or even euthanasia,” the researchers wrote in their study.

“In the case of comorbid aggression, they result in safety hazards and are of public concern. It has been demonstrated that in several canine neuropsychiatric disorders, the neurobiological base has similar characteristics as its human counterparts,” they added.

The researchers included 25 healthy beagle dogs in this study who were between one and eight years old. Each one of the dogs belonged to Ghent University’s Department of Veterinary Medical Imaging and Small Animal Orthopedics. The team monitored and assessed the dog’s health every three months and also studied their behavioral responses. The dogs had daily access to an enclosed playground and toys. In another group, the researchers studied the behaviors of 13 anxious dogs.

When it comes to dog behavior, the amygdala and hippocampus have been associated with the dog’s ability to remembering certain details and even getting aroused, excited, and scared. “Dysfunctions of these regions can lead to anxiety symptoms like more fear, less excitability, less trainability and so on, which are in line with previous human research,” the researchers noted. “A particular highlight of our results is the connection between the hippocampus and mesencephalon. Here, a less efficient communication was found between hippocampus and mesencephalon in the anxiety group.”

The mesencephalon or the mid brain that is responsible for vision, sleep and wakefulness, alertness, hearing, and motor control. “It has been reported that dys- function of the hippocampus and the mesencephalon is related with high risk for psychosis in humans,” they added.

A major limitation of the study is its small sample size of only 13 anxious dogs. Most of them were adopted from animal shelters where mistreatment is common and can affect or influence the brain’s anxiety networks. Also, the researchers acknowledged that dogs born and brought up in a lab will differ from healthy dogs raised in domestic environments.