Dogs know a left-sided wag from a right

October 31, 2013

You might think a wagging tail is a wagging tail, but for dogs there is more to it than that. Dogs recognize and respond differently when their fellow canines wag to the right than they do when they wag to the left. The findings reported in the Cell Press journal Current Biology on October 31 show that dogs, like humans, have asymmetrically organized brains, with the left and right sides playing different roles.

The discovery follows earlier work by the same Italian research team, which found that dogs wag to the right when they feel positive emotions (upon seeing their owners, for instance) and to the left when they feel negative emotions (upon seeing an unfriendly dog, for example). That biased tail-wagging behavior reflects what is happening in the dogs' brains. Left-brain activation produces a wag to the right, and right-brain activation produces a wag to the left.

But does that tail-wagging difference mean something to other dogs? Yes it does, the new study shows.

While monitoring their reactions, the researchers showed dogs videos of other dogs with either left- or right-asymmetric tail wagging. When dogs saw another dog wagging to the left, their heart rates picked up and they began to look anxious. When dogs saw another dog wagging to the right, they stayed perfectly relaxed.

"The direction of tail wagging does in fact matter, and it matters in a way that matches hemispheric activation," says Giorgio Vallortigara of the Center for Mind/Brain Sciences of the University of Trento. "In other words, a dog looking to a dog wagging with a bias to the right side--and thus showing left-hemisphere activation as if it was experiencing some sort of positive/approach response--would also produce relaxed responses. In contrast, a dog looking to a dog wagging with a bias to the left--and thus showing right-hemisphere activation as if it was experiencing some sort of negative/withdrawal response--would also produce anxious and targeting responses as well as increased cardiac frequency. That is amazing, I think."

Vallortigara doesn't think that the dogs are necessarily intending to communicate those emotions to other dogs. Rather, he says, the bias in tail wagging is likely the automatic byproduct of differential activation of the left versus the right side of the brain. But that's not to say that the bias in wagging and its response might not find practical uses; veterinarians and dog owners might do well to take note.

"It could be that left/right directions of approach could be effectively used by vets during visits of the animals or that dummies could be used to exploit asymmetries of emotional responses," Vallortigara says.
-end-
Current Biology, Siniscalchi et al.: "Seeing left or right asymmetric tail wagging produces different emotional responses in dogs."

Cell Press

Related Dogs Articles from Brightsurf:

Dogs are sensitive to their owners' choice despite their own preference
Inspired by work on infants, researchers investigated whether dogs' behaviors are guided by human displays of preference or by the animals' own choices.

Researchers identify new Rickettsia species in dogs
Researchers have identified a new species of Rickettsia bacteria that may cause significant disease in dogs and humans.

Paleogenomics -- the prehistory of modern dogs
An international team of scientists has used ancient DNA samples to elucidate the population history of dogs.

Tracking the working dogs of 9/11
A study of search and rescue dogs led by the School of Veterinary Medicine showed little difference in longevity or cause of death between dogs at the disaster site and dogs in a control group.

Fighting like cats and dogs?
We are all familiar with the old adage ''fighting like cat and dog'', but a new scientific study now reveals how you can bid farewell to those animal scraps and foster a harmonious relationship between your pet pooch and feline friend.

Why cats have more lives than dogs when it comes to snakebite
Cats are twice as likely to survive a venomous snakebite than dogs, and the reasons behind this strange phenomenon have been revealed by University of Queensland research.

Adolescence is ruff for dogs too
The study, headed by Dr Lucy Asher from Newcastle University, is the first to find evidence of adolescent behavior in dogs.

Urban dogs are more fearful than their cousins from the country
Inadequate socialisation, inactivity and an urban living environment are associated with social fearfulness in dogs.

Veterinarians: Dogs, too, can experience hearing loss
Just like humans, dogs are sometimes born with impaired hearing or experience hearing loss as a result of disease, inflammation, aging or exposure to noise.

Dogs and wolves are both good at cooperating
A team of researchers have found that dogs and wolves are equally good at cooperating with partners to obtain a reward.

Read More: Dogs News and Dogs Current Events
Brightsurf.com is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com.