Noam Chomsky’s (1957) review of Skinner’s book Verbal Behavior (that aimed to explain language acquisition in a behaviorist framework) is considered one of the major theoretical challenges to the type of radical behaviorism that Skinner taught. Chomsky showed that language could not be learned solely from the sort of operant conditioning that Skinner postulated. Chomsky’s argument was that people could produce an infinite variety of sentences unique in structure and meaning and that these could not possibly be generated solely through experience of natural language. As an alternative, he concluded that there must be internal mental structures – states of mind of the sort that behaviorism rejected as illusory. Similarly, work by Albert Bandura showed that children could learn by social observation, without any change in overt behaviour, and so must be accounted for by internal representations.
The rise of computer technology also promoted the metaphor of mental function as information processing. This, combined with a scientific approach to studying the mind, as well as a belief in internal mental states, led to the rise of cognitivism as the dominant model of the mind.
Links between brain and nervous system function were also becoming common, partly due to the experimental work of people like Charles Sherrington and Donald Hebb, and partly due to studies of people with brain injury (see cognitive neuropsychology). With the development of technologies for accurately measuring brain function, neuropsychology and cognitive neuroscience have become some of the most active areas in contemporary psychology. With the increasing involvement of other disciplines (such as philosophy, computer science, and neuroscience) in the quest to understand the mind, the umbrella discipline of cognitive science has been created as a means of focusing such efforts in a constructive way.
Dissenting schools
Not all psychologists, however, have been content to follow what they perceive as mechanical models of the mind and human nature.
Carl Jung, a one-time follower and contemporary of Freud, was instrumental in introducing notions of spirituality into Freudian psychoanalysis (Freud had rejected religion as a mass delusion). The soul is explored in-depth in the Neo-Jungian school of archetypal psychology.
Alfred Adler, after a brief association with Freud’s discussion circle, left to form his own discipline, called Individual (indivisible) Psychology. His influence on contemporary psychology has been considerable, with many approaches borrowing fragments of his theory. A recent rebirth of his legacy, Classical Adlerian Psychology, combines Adler’s original theory of personality, style of psychotherapy, and philosophy of living, with Abraham Maslow’s vision of optimal functioning.
Humanistic psychology emerged in the 1950s and has continued as a reaction to positivist and behaviorist approaches to the mind. It stresses a phenomenological view of human experience and seeks to understand human beings and their behavior by conducting qualitative research. The humanistic approach has its roots in existentialist and phenomenological philosophy and many humanist psychologists completely reject a scientific approach, arguing that trying to turn human experience into measurements strips it of all meaning and relevance to lived existence.
Some of the founding theorists behind this school of thought are Abraham Maslow, who formulated a hierarchy of human needs; Carl Rogers, who created and developed client centred therapy; and Fritz Perls, who helped create and develop Gestalt therapy.
A further development of Humanistic psychology emerging in the 1970s was Transpersonal psychology, which studies the spiritual dimension of humanity, looking at the possibilities for development beyond the normal ego-boundaries.