A small study in Austria found that balance is stabilized and destabilized when dogs hear both happy or angry human voices. However, the angry voices were the most destabilizing. In the new study, a team at the University of Veterinary Medicine in Vienna, Austria, measured changes in balance in 23 pet dogs upon hearing both happy and angry human voices. Angry human voices were associated with the most severe destabilization in 30 percent of dogs, while 70 percent did not show any changes to their balance. According to the team, these findings suggest that both happy and angry human voices can trigger an emotional response that affects a dog’s balance.