Psychology is the scientific study of the mind and behavior. Psychologists are actively involved in studying and understanding mental processes, brain functions, and behavior.

4 main types of psychology

There are different types of psychology, such as cognitive, forensic, social, and developmental psychology.

A professional practitioner or researcher involved in the discipline is called a psychologist. Some psychologists can also be classified as behavior or cognitive scientists. Some psychologists attempt to understand the role of mental functions in individual and social behavior. Others explore the physiological and neurobiological processes that underlie cognitive functions and behaviors.


The ancient civilizations of Egypt, Greece, China, India, and Persia all engaged in the philosophical study of psychology. In Ancient Egypt the Ebers Papyrus mentioned depression and thought disorders. Historians note that Greek philosophers, including Thales, Plato and Aristotle (especially in his De Anima treatise),addressed the workings of the mind. As early as the 4th century BC, the Greek physician Hippocrates  theorized that mental disorders had physical rather than supernatural causes.In 387 BCE, Plato suggested that the brain is where mental processes take place, and in 335 BCE Aristotle suggested that it was the heart.

Begining of experimental psychology:

Wilhelm wundt (seated) with colleagues in his psychological laboratory, the first of its kind

Philosopher John Stuart Mill believed that the human mind was open to scientific investigation, even if the science is in some ways inexact. Mill proposed a “mental chemistry ” in which elementary thoughts could combine into ideas of greater complexity. Gustav Fechner began conducting psycho physics research in Leipzig in the 1830s. He articulated the principle that human perception of a stimulus varies logarithmically according to its intensity. The principle became known as the Weber-Fechner-Law. Fechner’s 1860 Elements of Psychophysics challenged Kant’s negative view with regard to conducting quantitative research on the mind. Fechner’s achievement was to show that “mental processes could not only be given numerical magnitudes, but also that these could be measured by experimental methods.’ In Heidelberg, 

Development of psychology

Developmental psychologists would engage a child with a book and then make observations based on how the child interacts with the object.

Developmental psychology refers to the scientific study of how and why the thought processes, emotions, and behaviors of humans change over the course of their lives. Some credit Charles Darwin with conducting the first systematic study within the rubric of developmental psychology, having published in 1877 a short paper detailing the development of innate forms of communication based on his observations of his infant son. The main origins of the discipline, however, are found in the work of Jean Piaget. Like Piaget, developmental psychologists originally focused primarily on the development of cognition from infancy to adolescence. Later, developmental psychology extended itself to the study cognition over the life span. In addition to studying cognition, developmental psychologists have also come to focus on affective, behavioral, moral, social, and neural development.

Mental Healthcare:

The provision of psychological health services is generally called clinical psychology in the U.S. Sometimes, however, members of the school psychology and counseling psychology professions engage in practices that resemble that of clinical psychologists. Clinical psychologists typically include people who have graduated from doctoral programs in clinical psychology. In Canada, some of the members of the abovementioned groups usually fall within the larger category of professional psychology. In Canada and the U.S., practitioners get bachelor’s degrees and doctorates; doctoral students in clinical psychology usually spend one year in a predoctoral internship and one year in postdoctoral internship.