<Li> Developmental psychologist Jerome Kagan is a prominent advocate of type indicator theory . He suggests that shy, withdrawn children are best viewed as having an inhibited temperament, which is qualitatively different from that of other children . </Li> <Li> As a matter of convenience, trait theorists sometimes use the term type to describe someone who scores exceptionally high or low on a particular personality trait . Hans Eysenck refers to superordinate personality factors as types, and more specific associated traits as traits . </Li> <Li> Several pop psychology theories (e.g., Men Are From Mars, Women Are From Venus, the enneagram) rely on the idea of distinctively different types of people . </Li> <P> One of the more influential ideas originated in the theoretical work of Carl Jung as published in the book Psychological Types . The original German language edition, Psychologische Typen, was first published by Rascher Verlag, Zurich, in 1921 . Typologies such as Socionics, the MBTI assessment, and the Keirsey Temperament Sorter have roots in Jungian theory . </P>

Who describe the different types of personality based on glands