A research group at the Babraham Institute has found that the sight of a friendly face can reduce stress in sheep. This discovery, published in the journal Proceedings of the Royal Society: Biological Sciences, could point to the reason that many of us carry pictures of loved ones in our wallets or handbags.
The scientists, led by Professor Keith Kendrick, put sheep into a darkened barn on their own and showed them various faces, while recording their behaviour. Stress was measured by monitoring the number of times each sheep bleated, its movement within the barn and its heart-rate. Blood samples were taken to measure the levels of cortisol and adrenaline, which are both chemical indicators of stress.
When the sheep were shown faces of sheep familiar to them, they became less stressed, and showed fewer signs of agitation than when they were shown goat faces or triangles. The areas of the brain which control fear and the stress response also showed reduced activation.
All of the indicators of stress measured during the test showed significant reductions. These results provide evidence that face pictures may be useful for relieving stress caused by unavoidable social isolation in sheep, and possibly other animal species, including humans. Fear and emotion are controlled by the right-hand side of the brain of both sheep and humans.
Professor Kendrick comments “We are not aware of any studies investigating whether similar exposure to face pictures can decrease separation anxiety in humans although it is common practice to carry pictures of loved ones when separated from them. One method of relieving separation anxiety in young children may be to give them pictures of their parents to carry”.