The Cognitive Perspective:

The Cognitive perspective broadens the study of human psychology even further than the humanistic perspective. In addition to considering all of the influential elements within the behaviorist, psychodynamic, and humanistic views, cognitive psychology also studies the combined contributions of knowledge, memory, previous experience, subconscious desires, external factors, and volitional thought on external behavior (Gerrig & Zimbardo 2005).

Cognitive psychology accepts many of the fundamental concepts of other schools of psychological thought, and much like the humanistic point-of-view, merely considers them incomplete explanations of human behavior rather than oppositional theories.

According to cognitive psychologists, even the most inclusive theories like humanistic psychology are limited in their focus to passive elements while excluding more active elements of thought and action.

Unlike the other perspectives which fail to account for the importance of higher conscious thought and volitional responses, cognitive psychology examines the underlying explanations for purposeful behavioral responses (Gerrig & Zimbardo 2005).

The cognitive perspective also studies the many physiological phenomena and measurable changes in brain waves, circulation, hormone secretion, and volitional choices as well as their many consequences on the organism. The Biological and Evolutionary Perspectives:

The Biological and Evolutionary perspectives are two separate schools of psychological theory, but so closely related and complementary that they are best discussed together. The biological perspective views all outward human (and other biological organisms') behavior mainly as manifestations of physical changes occurring at the cellular level (Gerrig & Zimbardo 2005).

According to the strict biological perspective, every biological organism is naturally predisposed to certain patterns of behavior. Those patterns are susceptible to secondary influences, such as those described by competing theories of human psychology. However, even those responses to external factors are predictable because they are merely repeatable patterns that correspond to specific external influences on the organism's natural tendencies.

The Evolutionary perspective views the behavior of all biological organisms as the product of Darwin's Theory of Evolution through natural selection and genetic mutation over successive generations...

The essential difference between the evolutionary perspective and the strict biological perspective is that the latter considers external behavior as a reaction to environmental stimuli while the former considers external behavior as the inevitable outcome of tendencies dictated by evolutionary biology. The Cross-Cultural Perspective:
The Cross-Cultural or Socio-Cultural perspective of human behavior expands the study of human psychology beyond the realm of the individual to include one specific external influence; namely, the profound influential effect of the social society and culture in which human beings live. The cross-cultural view accepts many general propositions proposed by other psychological theories, but maintains that their significance is rivaled by the important contribution of learned social expectations and many other complex elements of cultural learning. As a result, the cross-cultural perspective suggests that the areas of focus essential to other perspectives neglects the degree to which even those valid observations reflect the influence of social learning and culture.

In particular, the cross-cultural perspective rejects certain aspects of the psychodynamic perspective, especially to the extent that the latter relies on Western social culture and family dynamics which vary substantially in other cultures.

Specifically, in 1927 anthropologist Bronislaw Mainowski pointed out that much of Freudian theory relies on the patriarchal family model and, therefore, is inherently inapplicable to many human societies where a matriarchal family structure is the norm (Gerrig & Zimbardo 2005).

Conclusion:

At their inception, the major schools of psychological thought reflected completely different approaches to understanding human behavior. As they developed, it eventually became clear that rather than being mutually exclusive in accuracy, each of the major perspectives contributes specific elements of the general pattern and causative factors manifested in the full spectrum of external behavior. Ultimately, the most comprehensive possible understanding of human behavior incorporates aspects of all of the major theories in relation to specific behaviors related to their individual foci. REFERENCES Coleman, J.C., Butcher, J.N., Carson, R.C. (1984) Abnormal Psychology and Human Life. Dallas: Scott, Foresman & Co. Gerrig, R, Zimbardo, P. (2005) Psychology and Life. 17th Edition.

New York: Allyn & Bacon.