Contemporary social thinkers have viewed anxiety as a
unique human emotion that can help as well as hurt
individuals throughout their lives. Spence saw anxiety as a
learned drive which energizes the organism (Levitt 1967) .
Anxiety can be a performance facilitator which increases an
individual's learning speed. Spielberger (1976) saw anxiety
as the central explanatory concept in almost all theories of
learning and psychopathology. Anxiety has also been
considered a main cause of such distinct behaviors as
insomnia, debilitating psychological and psychosomatic
symptoms, "immoral and sinful" acts, and instances of
creative self-expression.