If there are two things that pique my interest in life, it’s Biology and dogs (specifically pugs). So imagine my delight when I saw that there was an actual research paper in Current Biology all about dogs . The study showed that dogs can communicate their emotions with other canines through tail wagging. It has already been shown that tail wagging to the left is linked to anxiety while wagging to the right is linked with more positive emotions . What this new study showed was that dogs can actually respond to the left- or right-tail wagging of other pooches. It is thought that this behaviour is linked to the processing of different social queues in different sides of the brain [1,2].
In this study dogs were shown movies of other dogs wagging their tails more to the left or more to the right and the viewing dogs’ heart rate and behavioural reactions were recorded. The same experiment was also repeated with a silhouette of another dog, to reduce other social queues like facial expression. The results showed that the heart rates of dogs shown left-wagging went up, a sign of anxiety, while dogs shown right-wagging had a lower heart rate and relaxed behaviour.
Interestingly, when the canines were shown a movie of a still dog they had higher levels of anxiety than when shown a movie of a right-wagging dog. The authors proposed this may be due to confusion as the dogs tried to work out what the dog in the movie was doing or that this might be linked with human responses to neutral faces: in experiments where people were shown faces with neutral expressions they tended to assign negative emotions to them . Perhaps like the humans, these were pessimistic pooches.
These results are interesting in terms of understanding the nuances in social communication between dogs but also hint at something relatable to other animals. They also support the notion that processing of certain social situations can favour one side of the brain over the other. This may well help us understand our own brains better and aid research into how the brain responds to different emotions. All I know is, there should be more serious scientific studies that have this in the supplementary figures…
 Marcello Siniscalchi, Rita Lusito, Giorgio Vallortigara, Angelo Quaranta, Seeing Left- or Right-Asymmetric Tail Wagging Produces Different Emotional Responses in Dogs, Current Biology, 2013.
 Claire L. Roether, Lars Omlor, Martin A. Giese, Lateral asymmetry of bodily emotion expression, Current Biology, Volume 18, Issue 8, 22, 2008.
 Eun Lee, Jee In Kang, Il Ho Park, Jae-Jin Kim, Suk Kyoon An, Is a neutral face really evaluated as being emotionally neutral?, Psychiatry research, volume 157 issue 1, 2008.
By Liz Granger