Biological psychology fundamentals and applications

Psychology - Biological Psychology

BIOLOGICAL PSYCHOLOGICAL CONCEPTS

The Origin and Development of Biological Theories of Psychology:

The earliest known origin of biological theories of human psychology go back to antiquity, as much as a millennium before the Common Era. More recently, classical philosophers of the Middle Ages, and later, of the post-Enlightenment era considered the relationship of biology and human psychology in relation to concepts of free will, biological determinism, and moral responsibility (Pinker, 2002). In the 17th century, Rene Descartes postulated that all human behavior could be explained by a sufficiently detailed understanding of biological processes and systemic reactions (Gerrig & Zimbardo, 2005).

In the 19th century, Paul Broca investigated the role of brain injury and abnormalities in relation to human speech. Broca was eventually able to establish through empirical evidence that a specific region of the brain was responsible for human speech; in connection with that discovery, the region was later named Broca's area in recognition of the importance of his foundational work in the field of biopsychology (Gerrig & Zimbardo, 2005). At approximately the same time, the both the medical world and the emerging field of neuropsychology were advanced substantially by the accident that occurred to railway worker Phineas Gage in 1848.

Gage had been the victim of an explosion accident that caused a 3-foot, 7-inch steel rod to pierce his skull and lodge itself through his brain, its ends protruding from below his left eye socket and from the top of his skull in the area of the frontal cortex.

The fact that Gage survived in the pre-antibiotic era of medicine and before Lister's Germ Theory of disease was unexpected. The fact that he did provided some of the earliest evidence of the extent to which specific areas of the brain are responsible for specific aspects of human personality (Dennet, 1991). Gage survived the accident but with significant personality changes that were attributable directly to the destruction of a portion of his frontal cortex.

Major Underlying Assumption of Biological Theory of Psychology:

The major underlying assumptions of biological theories of psychology are that psychological behavior is merely the external expression of variations in biological structure, processes, and responses to stimuli. According to the bio-psychological or neurophysiological theory of human behavior, hard-wired elements of brain structure and other individual characteristics of biological structure determine the way that organisms respond to the external environment. This perspective conceives of all psychological behavior as functions of neurological and endocrinal systems and structure and suggests that biology is much more responsible for behavior than learned behavior or natural responses to external factors (Gerrig & Zimbardo, 2005).

Important Theorists and their Contributions:

Broca contributed greatly to the initial recognition of the importance of specific brain regions to particular aspects of human psychology and behavior in the middle of the 19th century. Shortly thereafter, William James published one of the first formal academic explanation of biopsychology just before the turn of the 20th century, titled the Principles of Psychology (Dennet, 1991; Pinker, 2002). James acknowledged that personal experience and external environmental factors played a role in human psychological development, but only in so far as they represent sets and types of automatic, involuntary, and inherent biological responses to circumstances (Dennet, 1991).

Approximately 60 years later, Walter Hess pioneered a method of directly exploring the role of specific brain regions and structures through the use of electro- stimulation (Gerrig & Zimbardo, 2005). By implanting electrodes into anesthetized laboratory animals, Hess demonstrated that specific behaviors could be triggered by electrically stimulating the areas of the brain responsible for certain behaviors.