“In the early days of psychology there were two dominant theoretical perspectives regarding how the brain worked, structuralism and functionalism.
Structuralism was the name given to the approach pioneered by Wilhelm Wundt (1832-1920), which focused on breaking down mental processes intro the most basic components.
The term originated from Edward Titchener, an American psychologist who had been trained by Wundt. Wundt was important because he separated psychology from philosophy by analyzing the workings of the mind in a more structured way, with the emphasis being on objective measurement and control.
Structuralism relied on trained introspection, a research method whereby subjects related what was going on in their minds while performing a certain task.
However, introspection proved to be an unreliable method because there was too much individual variation in the experiences and reports of research subjects.
Despite the failure of introspection Wundt is an important figure in the history of psychology as he opened the first laboratory dedicated to psychology in 1879, and its opening is usually thought of as the beginning of modern experimental psychology.
An American psychologist named William James (1842-1910) developed an approach which came to be known as functionalism, that disagreed with the focus of Structuralism.
James argued that the mind is constantly changing and it is pointless to look for the structure of conscious experience. Rather, he proposed the focus should be on how and why an organism does something, i.e. the functions or purpose of the brain.
James suggested that psychologists should look for the underlying cause of behavior and the mental processes involved. This emphasis on the causes and consequences of behavior has influenced contemporary psychology.”