EmpathyYawningImitative BehaviorPan paniscusPair BondPan troglodytesEmotionsSocial BehaviorFriendsStudents, MedicalPhysician-Patient RelationsBehavior, AnimalTheory of MindDentist-Patient RelationsSocial PerceptionSex CharacteristicsNarcissismStudents, PremedicalPain Insensitivity, CongenitalAltruismNonverbal CommunicationFacial Expression