Psychologists today do not believe there is one “right” way to study the way people think or behave. There are, however, various schools of thought that evolved throughout the development of psychology that continue to shape the way psychologists investigate human behavior. For example, some psychologists might attribute a certain behavior to biological factors such as genetics while another psychologist might consider early childhood experiences to be a more likely explanation for the behavior. Because psychologists might emphasize various points within psychology in their research and analysis of behavior, there are different viewpoints in psychology. These schools of thought are known as approaches, or perspectives.

The Psychodynamic Perspective

Psychodynamic theory is an approach to psychology that studies the psychological forces underlying human behavior, feelings, and emotions, and how they may relate to early childhood experience. This theory is especially interested in the dynamic relations between conscious and unconscious motivation, and asserts that behavior is the product of underlying conflicts over which people often have little awareness.

Psychodynamic theory was born in 1874 with the works of German scientist Ernst von Brucke, who supposed that all living organisms are energy systems governed by the principle of the conservation of energy. During the same year, medical student Sigmund Freud adopted this new “dynamic” physiology and expanded it to create the original concept of “psychodynamics,” in which he suggested that psychological processes are flows of psychosexual energy (libido) in a complex brain. Freud also coined the term “psychoanalysis.” Later, these theories were developed further by Carl Jung, Alfred Adler, Melanie Klein, and others. By the mid-1940s and into the 1950s, the general application of the “psychodynamic theory” had been well established.

The Role of the Unconscious

Freud’s theory of psychoanalysis holds two major assumptions: (1) that much of mental life is unconscious (i.e., outside of awareness), and (2) that past experiences, especially in early childhood, shape how a person feels and behaves throughout life. The concept of the unconscious was central: Freud postulated a cycle in which ideas are repressed but continue to operate unconsciously in the mind, and then reappear in consciousness under certain circumstances. Much of Freud’s theory was based on his investigations of patients suffering from “hysteria” and neurosis. Hysteria was an ancient diagnosis that was primarily used for women with a wide variety of symptoms, including physical symptoms and emotional disturbances with no apparent physical cause. The history of the term can be traced to ancient Greece, where the idea emerged that a woman’s uterus could float around her body and cause a variety of disturbances. Freud theorized instead that many of his patients’ problems arose from the unconscious mind. In Freud’s view, the unconscious mind was a repository of feelings and urges of which we have no awareness.

The treatment of a patient referred to as Anna O. is regarded as marking the beginning of psychoanalysis. Freud worked together with Austrian physician Josef Breuer to treat Anna O.’s “hysteria,” which Freud implied was a result of the resentment she felt over her father’s real and physical illness that later led to his death. Today many researchers believe that her illness was not psychological, as Freud suggested, but either neurological or organic.

The Id, Ego, and Superego

Freud’s structural model of personality divides the personality into three parts—the id, the ego, and the superego. The id is the unconscious part that is the cauldron of raw drives, such as for sex or aggression. The ego, which has conscious and unconscious elements, is the rational and reasonable part of personality. Its role is to maintain contact with the outside world to keep the individual in touch with society, and to do this it mediates between the conflicting tendencies of the id and the superego. The superego is a person’s conscience, which develops early in life and is learned from parents, teachers, and others. Like the ego, the superego has conscious and unconscious elements. When all three parts of the personality are in dynamic equilibrium, the individual is thought to be mentally healthy. However, if the ego is unable to mediate between the id and the superego, an imbalance is believed to occur in the form of psychological distress.

Psychosexual Theory of Development

Freud’s theories also placed a great deal of emphasis on sexual development. Freud believed that each of us must pass through a series of stages during childhood, and that if we lack proper nurturing during a particular stage, we may become stuck or fixated in that stage. Freud’s psychosexual model of development includes five stages: oral, anal, phallic, latency, and genital. According to Freud, children’s pleasure-seeking urges are focused on a different area of the body, called an erogenous zone, at each of these five stages. Psychologists today dispute that Freud’s psychosexual stages provide a legitimate explanation for how personality develops, but what we can take away from Freud’s theory is that personality is shaped, in some part, by experiences we have in childhood.

Jungian Psychodynamics

Carl Jung was a Swiss psychotherapist who expanded upon Freud’s theories at the turn of the 20th century. A central concept of Jung’s analytical psychology is individuation: the psychological process of integrating opposites, including the conscious with the unconscious, while still maintaining their relative autonomy. Jung focused less on infantile development and conflict between the id and superego and instead focused more on integration between different parts of the person. Jung created some of the best-known psychological concepts, including the archetype, the collective unconscious, the complex, and synchronicity.

Psychodynamics Today

At present, psychodynamics is an evolving multidisciplinary field that analyzes and studies human thought processes, response patterns, and influences. Research in this field focuses on areas such as:

• understanding and anticipating the range of conscious and unconscious responses to specific sensory inputs, such as images, colors, textures, sounds, etc.;
• utilizing the communicative nature of movement and primal physiological gestures to affect and study specific mind-body states; and
• examining the capacity of the mind and senses to directly affect physiological response and biological change.

Psychodynamic therapy, in which patients become increasingly aware of dynamic conflicts and tensions that are manifesting as a symptom or challenge in their lives, is an approach to therapy that is still commonly used today.

Behavioral Perspective

Behaviorism is an approach to psychology that emerged in the early 20th century as a reaction to the psychoanalytic theory of the time. Psychoanalytic theory often had difficulty making predictions that could be tested using rigorous experimental methods. The behaviorist school of thought maintains that behaviors can be described scientifically without recourse either to internal physiological events or to hypothetical constructs such as thoughts and beliefs. Rather than focusing on underlying conflicts, behaviorism focuses on observable, overt behaviors that are learned from the environment.

Its application to the treatment of mental problems is known as behavior modification. Learning is seen as behavior change molded by experience; it is accomplished largely through either classical or operant conditioning (described below).

The primary developments in behaviorism came from the work of Ivan Pavlov, John B. Watson, Edward Lee Thorndike, and B. F. Skinner.

Ivan Pavlov and Classical Conditioning

The Russian physiologist Ivan Pavlov was widely known for describing the phenomenon now known as classical conditioning. In his famous 1890s experiment, he trained his dogs to salivate on command by associating the ringing of a bell with the delivery of food. As Pavlov’s work became known in the West, particularly through the writings of John B. Watson, the idea of conditioning as an automatic form of learning became a key concept in the development of behaviorism.

Watson’s “Little Albert” Experiment

John B. Watson was an American psychologist who is best known for his controversial “Little Albert” experiment. In this experiment, he used classical conditioning to teach a nine-month-old boy to be afraid of a white toy rat by associating the rat with a sudden loud noise. This study demonstrated how emotions could become conditioned responses.

Thorndike’s Law of Effect

Edward Lee Thorndike was an American psychologist whose work on animal behavior and the learning process led to the “law of effect.” The law of effect states that responses that create a satisfying effect are more likely to occur again, while responses that produce a discomforting effect become less likely to occur.

Skinner’s Operant Conditioning

“Operant conditioning,” a term coined by psychologist B. F. Skinner, describes a form of learning in which a voluntary response is strengthened or weakened depending on its association with either positive or negative consequences. The strengthening of a response occurs through reinforcement. Skinner described two types of reinforcement: positive reinforcement, which is the introduction of a positive consequence such as food, pleasurable activities, or attention from others, and negative reinforcement, which is the removal of a negative consequence such as pain or a loud noise. Skinner saw human behavior as shaped by trial and error through reinforcement and punishment, without any reference to inner conflicts or perceptions. In his theory, mental disorders represented maladaptive behaviors that were learned and could be unlearned through behavior modification.

Behaviorism Today

In the second half of the 20th century, behaviorism was expanded through advances in cognitive theories. While behaviorism and cognitive schools of psychological thought may not agree theoretically, they have complemented each other in practical therapeutic applications like cognitive-behavioral therapy (CBT), which has been used widely in the treatment of many different mental disorders, such as phobias, PTSD, and addiction.

Some behavior therapies employ Skinner’s theories of operant conditioning: by not reinforcing certain behaviors, these behaviors can be extinguished. Skinner’s radical behaviorism advanced a “triple contingency” model, which explored the links between the environment, behavior, and the mind. This later gave rise to applied behavior analysis (ABA), in which operant conditioning techniques are used to reinforce positive behaviors and punish unwanted behaviors. This approach to treatment has been an effective tool to help children on the autism spectrum; however, it is considered controversial by many who see it as attempting to change or “normalize” autistic behaviors (Lovaas, 1987, 2003; Sallows & Graupner, 2005; Wolf & Risley, 1967).

The Cognitive Perspective

Cognitive psychology is the school of psychology that examines internal mental processes such as problem solving, memory, and language. “Cognition” refers to thinking and memory processes, and “cognitive development” refers to long-term changes in these processes. Much of the work derived from cognitive psychology has been integrated into various other modern disciplines of psychological study, including social psychology, personality psychology, abnormal psychology, developmental psychology, educational psychology, and behavioral economics.

Cognitive psychology is radically different from previous psychological approaches in that it is characterized by both of the following:

1. It accepts the use of the scientific method and generally rejects introspection as a valid method of investigation, unlike phenomenological methods such as Freudian psychoanalysis.
2. It explicitly acknowledges the existence of internal mental states (such as belief, desire, and motivation), unlike behaviorist psychology.

Cognitive theory contends that solutions to problems take the form of algorithms, heuristics, or insights. Major areas of research in cognitive psychology include perception, memory, categorization, knowledge representation, numerical cognition, language, and thinking.

History of Cognitive Psychology

Cognitive psychology is one of the more recent additions to psychological research. Though there are examples of cognitive approaches from earlier researchers, cognitive psychology really developed as a subfield within psychology in the late 1950s and early 1960s. The development of the field was heavily influenced by contemporary advancements in technology and computer science.

Early Roots

In 1958, Donald Broadbent integrated concepts from human-performance research and the recently developed information theory in his book Perception and Communication, which paved the way for the information-processing model of cognition. Ulric Neisser is credited with formally having coined the term “cognitive psychology” in his book of the same name, published in 1967. The perspective had its foundations in the Gestalt psychology of Max Wertheimer, Wolfgang Köhler, and Kurt Koffka, and in the work of Jean Piaget, who studied intellectual development in children.

Although no one person is entirely responsible for starting the cognitive revolution, Noam Chomsky was very influential in the early days of this movement. Chomsky (1928–), an American linguist, was dissatisfied with the influence that behaviorism had had on psychology. He believed that psychology’s focus on behavior was short-sighted and that the field had to reincorporate mental functioning into its purview if it were to offer any meaningful contributions to understanding behavior (Miller, 2003).

Jean Piaget’s Theory of Cognitive Development

Instead of approaching development from a psychoanalytic or psychosocial perspective, Piaget focused on children’s cognitive growth. He is most widely known for his stage theory of cognitive development, which outlines how children become able to think logically and scientifically over time. As they progress to a new stage, there is a distinct shift in how they think and reason.

The Humanistic Perspective

Humanistic psychology is a psychological perspective that rose to prominence in the mid-20th century, drawing on the philosophies of existentialism and phenomenology, as well as Eastern philosophy. It adopts a holistic approach to human existence through investigations of concepts such as meaning, values, freedom, tragedy, personal responsibility, human potential, spirituality, and self-actualization.

Basic Principles of the Humanistic Perspective

The humanistic perspective is a holistic psychological perspective that attributes human characteristics and actions to free will and an innate drive for self-actualization. This approach focuses on maximum human potential and achievement rather than psychoses and symptoms of disorder. It emphasizes that people are inherently good and pays special attention to personal experiences and creativity. This perspective has led to advances in positive, educational, and industrial psychology, and has been applauded for its successful application to psychotherapy and social issues. Despite its great influence, humanistic psychology has also been criticized for its subjectivity and lack of evidence.

Developments in Humanistic Psychology

In the late 1950s, a group of psychologists convened in Detroit, Michigan, to discuss their interest in a psychology that focused on uniquely human issues, such as the self, self-actualization, health, hope, love, creativity, nature, being, becoming, individuality, and meaning. These preliminary meetings eventually culminated in the description of humanistic psychology as a recognizable “third force” in psychology, along with behaviorism and psychoanalysis. Humanism’s major theorists were Abraham Maslow, Carl Rogers, Rollo May, and Clark Moustakas; it was also influenced by psychoanalytic theorists, including Wilhelm Reich, who discussed an essentially good, healthy core self, and Carl Gustav Jung, who emphasized the concept of archetypes.

Maslow’s Hierarchy of Needs

Abraham Maslow (1908–1970) is considered the founder of humanistic psychology, and is noted for his conceptualization of a hierarchy of human needs. He believed that every person has a strong desire to realize his or her full potential—or to reach what he called “self-actualization.” Unlike many of his predecessors, Maslow studied mentally healthy individuals instead of people with serious psychological issues. Through his research he coined the term “peak experiences,” which he defined as “high points” in which people feel at harmony with themselves and their surroundings. Self-actualized people, he believed, have more of these peak experiences throughout a given day than others.

To explain his theories, Maslow created a visual, which he termed the “hierarchy of needs.” This pyramid depicts various levels of physical and psychological needs that a person progresses through during their lifetime. At the bottom of the pyramid are the basic physiological needs of a human being, such as food and water. The next level is safety, which includes shelter and needs paramount to physical survival. The third level, love and belonging, is the psychological need to share oneself with others. The fourth level, esteem, focuses on success, status, and accomplishments. The top of the pyramid is self-actualization, in which a person is believed to have reached a state of harmony and understanding. Individuals progress from lower to higher stages throughout their lives, and cannot reach higher stages without first meeting the lower needs that come before them.

Rogers’ Person-Centered Therapy

Carl Rogers (1902–1987) is best known for his person-centered approach, in which the relationship between therapist and client is used to help the patient reach a state of realization, so that they can then help themselves. His non-directive approach focuses more on the present than the past and centers on clients’ capacity for self-direction and understanding of their own development. The therapist encourages the patient to express their feelings and does not suggest how the person might wish to change. Instead, the therapist uses the skills of active listening and mirroring to help patients explore and understand their feelings for themselves.

Rogers is also known for practicing “unconditional positive regard,” which is defined as accepting a person in their entirety with no negative judgment of their essential worth. He believed that those raised in an environment of unconditional positive regard have the opportunity to fully actualize themselves, while those raised in an environment of conditional positive regard only feel worthy if they match conditions that have been laid down by others.

May’s Existentialism

Rollo May (1909–1994) was the best known American existential psychologist, and differed from other humanistic psychologists by showing a sharper awareness of the tragic dimensions of human existence. May was influenced by American humanism, and emphasized the importance of human choice.

Advantages and Disadvantages

Humanistic psychology is holistic in nature: it takes whole persons into account rather than their separate traits or processes. In this way, people are not reduced to one particular attribute or set of characteristics, but instead are appreciated for the complex beings that they are. Humanistic psychology allows for a personality concept that is dynamic and fluid and accounts for much of the change a person experiences over a lifetime. It stresses the importance of free will and personal responsibility for decision-making; this view gives the conscious human being some necessary autonomy and frees them from deterministic principles. Perhaps most importantly, the humanistic perspective emphasizes the need to strive for positive goals and explains human potential in a way that other theories cannot.

However, critics have taken issue with many of the early tenets of humanism, such as its lack of empirical evidence (as was the case with most early psychological approaches). Because of the inherent subjective nature of the humanistic approach, psychologists worry that this perspective does not identify enough constant variables in order to be researched with consistency and accuracy. Psychologists also worry that such an extreme focus on the subjective experience of the individual does little to explain or appreciate the impact of external societal factors on personality development. In addition, The major tenet of humanistic personality psychology—namely, that people are innately good and intuitively seek positive goals—does not account for the presence of deviance in the world within normal, functioning personalities.

The Socio-Cultural Perspective

Sociocultural factors are the larger-scale forces within cultures and societies that affect the thoughts, feelings, and behaviors of individuals. These include forces such as attitudes, child-rearing practices, discrimination and prejudice, ethnic and racial identity, gender roles and norms, family and kinship structures, power dynamics, regional differences, religious beliefs and practices, rituals, and taboos. Several subfields within psychology seek to examine these sociocultural factors that influence human mental states and behavior; among these are social psychology (discussed in another section), cultural psychology, and cultural-historical psychology.

Cultural Psychology

Cultural psychology is the study of how psychological and behavioral tendencies are rooted and embedded within culture. The main tenet of cultural psychology is that mind and culture are inseparable and mutually constitutive, meaning that people are shaped by their culture and their culture is also shaped by them.

A major goal of cultural psychology is to expand the number and variation of cultures that contribute to basic psychological theories, so that these theories become more relevant to the predictions, descriptions, and explanations of all human behaviors—not just Western ones. Populations that are Western, educated, and industrialized tend to be overrepresented in psychological research, yet findings from this research tend to be labeled “universal” and inaccurately applied to other cultures. The evidence that social values, logical reasoning, and basic cognitive and motivational processes vary across populations has become increasingly difficult to ignore. By studying only a narrow range of culture within human populations, psychologists fail to account for a substantial amount of diversity.

Cultural psychology is often confused with cross-cultural psychology; however, it is distinct in that cross-cultural psychologists generally use culture as a means of testing the universality of psychological processes, rather than determining how local cultural practices shape psychological processes. So while a cross-cultural psychologist might ask whether Jean Piaget’s stages of development are universal across a variety of cultures, a cultural psychologist would be interested in how the social practices of a particular set of cultures shape the development of cognitive processes in different ways.

Vygotsky and Cultural-Historical Psychology

Cultural-historical psychology is a psychological theory formed by Lev Vygotsky in the late 1920s and further developed by his students and followers in Eastern Europe and worldwide. This theory focuses on how aspects of culture, such as values, beliefs, customs, and skills, are transmitted from one generation to the next. According to Vygotsky, social interaction—especially involvement with knowledgeable community or family members—helps children to acquire the thought processes and behaviors specific to their culture and/or society. The growth that children experience as a result of these interactions differs greatly between cultures; this variance allows children to become competent in tasks that are considered important or necessary in their particular society.

The Biological Perspective

Biopsychology—also known as biological psychology or psychobiology—is the application of the principles of biology to the study of mental processes and behavior. The fields of behavioral neuroscience, cognitive neuroscience, and neuropsychology are all subfields of biological psychology.

Overview of Biopsychology

Biopsychologists are interested in measuring biological, physiological, and/or genetic variables and attempting to relate them to psychological or behavioral variables. Because all behavior is controlled by the central nervous system, biopsychologists seek to understand how the brain functions in order to understand behavior. Key areas of focus include sensation and perception, motivated behavior (such as hunger, thirst, and sex), control of movement, learning and memory, sleep and biological rhythms, and emotion. As technical sophistication leads to advancements in research methods, more advanced topics, such as language, reasoning, decision-making, and consciousness, are now being studied.

Behavioral neuroscience has a strong history of contributing to the understanding of medical disorders, including those that fall into the realm of clinical psychology. Neuropsychologists are often employed as scientists to advance scientific or medical knowledge, and neuropsychology is particularly concerned with understanding brain injuries in an attempt to learn about normal psychological functioning. Neuroimaging tools, such as functional magnetic resonance imaging (fMRI) scans, are often used to observe which areas of the brain are active during particular tasks in order to help psychologists understand the link between brain and behavior.

History

Biopsychology as a scientific discipline emerged from a variety of scientific and philosophical traditions in the 18th and 19th centuries. Philosophers like Rene Descartes proposed physical models to explain animal and human behavior. Descartes suggested, for example, that the pineal gland, a midline unpaired structure in the brain of many organisms, was the point of contact between mind and body. In The Principles of Psychology (1890), William James argued that the scientific study of psychology should be grounded in an understanding of biology. The emergence of both psychology and behavioral neuroscience as legitimate sciences can be traced to the emergence of physiology during the 18th and 19th centuries; however, it was not until 1914 that the term “psychobiology” was first used in its modern sense by Knight Dunlap in An Outline of Psychobiology.