Emotional contagion in dogs as measured by change in cognitive task performance

•Stress has an improving effect on the humans’ and dogs’ memory performance.•Dogs’ memory performance can be affected by their owners’ stress level.•Our results support for the emotional contagion between dogs and their owners.

Domestic dogs are living with humans in a very special inter-species relationship. Previous studies have shown physiological and hormonal synchronisation between dogs and their owners during positive interaction. Dogs are also known to be able to discriminate human emotions and they were also presupposed to have the capacity to empathise with humans. Based on these results we hypothesize that the owner's emotions can be contagious to the dog and stress-related emotional changes in dogs can be tracked by memory tasks because both human and nonhuman studies indicate a significant effect of perceived stress on subjects’ cognitive performance. In the present study the owners, after having completed State Anxiety Inventory and having participated in a memory task, were manipulated with either negative (Stressed owner condition) or positive (Non-stressed owner condition) verbal feedback in an additional task. Results indicate that the owners’ self-reported anxiety significantly increased in the Stressed owner condition due to the manipulation. We also measured the effect of the different manipulations on the owners’ and also on their dogs’ memory performance and found that in line with earlier studies the stress-evoking intervention had an improving effect on the owners’ memory performance. After separation from their owner (Stressed dog condition) dogs also showed better performance in a spatial working memory task and, more interestingly, task completion was also affected by the manipulation of their owners stress level. These findings provide further support for the emotional contagion between dogs and their owners, and suggest that measuring changes in the memory performance can be used as an indicator of contagion-induced changes in dogs’ stress level.