There are different forms of empathy recognized in literature. Emotional empathy is a form of emotional mirroring, where the empathizer feels the emotions of others. With time, this may lead to emotional strain, particularly for medical staff. Cognitive empathy is the ability to see the perspective of others, without feeling any emotions. While it is a useful skill, it relies on logic and rational thinking, without any fellow-feeling. Studies have shown that doctors lose much of their emotional empathy and revert to cognitive empathy, possibly to protect themselves emotionally. In between those two extremes is Compassionate empathy, which is a balance between the two.