Starting from a biological perspective, it is possible to analyze the human brain in terms of its very low-level characteristics. We know that the brain is comprised of billions of neurons that communicate messages by altering the balance of certain chemicals at connections between the neurons called synapses. These neurons combine in an indescribably complicated web to maintain and communicate signals around the brain and the broader nervous system. Zooming out, these neurons are organized into numerous different systems within the brain itself. We consider these organizations in terms of two elements: hemispheres and lobes. The brain has two hemispheres (left and right), and four primary lobes: the temporal lobe, parietal lobe, occipital lobe and frontal lobe.
The brain is a remarkably complicated organ, but biologically that organization describes its overall structure. In order to analyze the brain further, it is important to consider it in terms of its functions. For example, different lobes take care of different conscious and subconscious processes. There are specific areas of the brain devoted to language, motor skills, reasoning, memory, and numerous other categories.
However, there exists a strong disconnect between our biological knowledge of the brain and our psychological knowledge of the brain. We know its structure and some general categories of what portions of the structure correspond to what behaviors, but we lack a true understanding of how the brain actually accomplishes the numerous tasks it performs.
Thus, from the biological level, there exists a gap up to the true schools of thought of psychology. While the major schools of thought do give some attention to biology, they largely conduct their research and formulate their theories based on an abstracted form of the brain as a biological entity. As we will see, the different schools of thought consider the brain everything from a mysterious “black box” that can never be understood to a complex but accessible machine, only a few levels above the biological level.
Starting from the “black box” end of that spectrum is the classic notion of behaviorism. In behaviorism, little or no attention is paid to the actual processes that take place within the brain. Behaviorists are concerned only with the input into the brain, and the output the follows it. The origins of behaviorism can be traced to Ivan Pavlov's classical conditioning (Pavlov 1927) and and Burrhus Skinner's operant conditioning (Skinner 1938). In these theories, these and other psychologists suggest that the human brain is a product of past experienced stimuli and learned responses to those stimuli. They do not seek to explain internal processes within the brain.
Following behaviorism, the next major school of psychological thought was Sigmund Freud's psychoanalysis. In psychoanalysis, Freud posits the existence of three influencing factors within the brain: the id, the ego and the superego. While the id puts forward the innate desires of mankind (food, reproduction, safety), the superego emphasizes the cultural and societal objectives of the individual. The ego manages the two along with the individual's personal desires. Psychoanalysis regards XXXXX XXXXX between the three parts as an underlying process, indicating more attention to the way the brain works than behaviorism; however, this occurs only at a high level, analyzing the effects of this conflict more than the conflict itself. While this attitude has received notable attention, it has not presented much evidence or practical results; however, it is important for introducing the notion of “unconscious” processes.
Behaviorism and psychoanalysis both have a similar characteristic, however: both put forward a very dim view of humanity. One views humanity as little more than a behavioral machine, while the other keeps mankind on approximately the same level as animals. In response to these, Maslow's humanistic psychology emerged. Maslow and other humanists placed a special emphasis on individual will, growth and development (Maslow 1954). They put forward the notions of very human ideas, such as the urge for acceptance, fulfillment and self-actualization. Like psychoanalysis, this viewpoint gives some service to how the brain actually operates, but only in high level terms: it acknowledges driving forces and desires, but not how those emerge and are balanced at a practical level. While this viewpoint is important for its more forgiving view of humanity, it also has not presented many practical takeaways or results.
The most recent school of psychological thought is that of cognitive psychology. Unlike the three previous schools of thought, cognitive psychology makes a special effort to analyzing how the brain actually reasons and learns. Perception, memory and general thought are all key considerations of cognitive psychology. It is important to note that cognitive psychology does aim to explain the same phenomena as other schools of thought: it is concerned with forming an actual theory as to why behaviors emerge, while other viewpoints only aim to describe what behaviors emerge. The belief with cognitive psychology is that a better understanding of how certain mental processes take place will lead to better external tools and affordances for those thoughts. For example, teachers could be more effective if they knew the natural way in which the human mind learns in the real world, outside the classroom.
As should be clear, however, none of these schools of thought possess a strong tie to their biological basis. The brain is simultaneously complex and simple, forming complicated webs out of a generally simple underlying structure. Generating a full theory of psychology that considers both the biological basis and the emergent behaviors will require continued bottom-up and top-down analysis.
B. F. Skinner. (1938). The Behavior of Organisms: An Experimental Analysis. Cambridge, Massachusetts: B. F. Skinner Foundation.
Maslow, Abraham (1954). Motivation and Personality. New York: Harper. pp. 236.
Pavlov, I. P. (1927). Conditioned Reflexes: An Investigation of the Physiological Activity of the Cerebral Cortex. Translated and Edited by G. V. Anrep. London: Oxford University Press.