Dog owners tend to have personalities that are similar to those of their dogs, with studies showing that they share many of the same personality dimensions, such as neuroticism, extraversion, conscientiousness, and agreeableness. A calm human will often choose a calm dog, or an anxious person will adopt a frightened dog, for example. People do this on a subconscious level, and the dogs have maintained, and even strengthened, some of these personality traits through the years. Some dog owners have neurotic tendencies and gravitate towards higher-energy dogs, such as Weimaraners, Viszlas, herding dogs, and other breeds that often feed off of the amped-up energy of their owners. Dogs can sense minute physiologic changes in people and other animals and respond accordingly, and they frequently try to comfort and calm upset owners. The closer the human-animal relationship, the greater the response, and dogs can also impact humans, with anxious dogs often resulting in owner anxiety.