During the late 1800s, brain–behavior relationships were interpreted by European physicians who observed and identified behavioral syndromes that were related to focal brain dysfunction. Clinical neuropsychology is a fairly new practice in comparison to other specialty fields in psychology, with a history going back to the 1960s. Parts of
neurology, clinical psychology,
psychiatry,
cognitive psychology, and
psychometrics have all been applied together to create clinical neuropsychology, a practice that is very much so still evolving. The history of clinical neuropsychology is long and complicated due to its ties to so many older practices. Researchers like
Thomas Willis, who has been credited with creating neurology;
John Hughlings Jackson, who theorized that cognitive processes occurred in specific parts of the brain;
Paul Broca and
Karl Wernicke, who studied the human brain in relation to psychopathology; and
Jean Martin Charcot, who apprenticed
Sigmund Freud, who created the psychoanalytic theory, all contributed to clinical medicine, which later contributed to clinical neuropsychology. The field of psychometrics contributed to clinical neuropsychology through individuals such as
Francis Galton, who collected quantitative data on physical and sensory characteristics;
Karl Pearson, who established the statistics that psychology now relies on;
Wilhelm Wundt, who created the first psychology lab; his student
Charles Spearman, who furthered statistics through discoveries like factor analysis;
Alfred Binet and his apprentice
Theodore Simon, who together made the Binet–Simon scale of intellectual development; and
Jean Piaget, who studied child development. Studies in intelligence testing made by Lewis Terman, who updated the Binet–Simon scale to the
Stanford–Binet Intelligence Scales;
Henry Goddard, who developed different classification scales; and
Robert Yerkes, who was in charge of the Army Alpha and Beta tests, also all contributed to where clinical neuropsychology is today. Clinical neuropsychology focuses on the brain and goes back to the beginning of the 20th century. As a clinician, a clinical neuropsychologist offers their services by addressing three steps: assessment, diagnosis, and treatment. The term "clinical neuropsychologist" was first used by Sir William Osler on April 16, 1913. While clinical neuropsychology was not a focus until the 20th century, evidence of brain and behavior treatment and studies are seen as far back as the
Neolithic era, when trephination, a crude surgery in which a piece of the skull is removed, was observed in skulls. During
World War I, the early term "shell shock" was first observed in soldiers who survived the war. This was the beginning of efforts to understand traumatic events and how they affected people. During the
Great Depression, further stressors caused shell shock-like symptoms to emerge. In
World War II, the term "shell shock" was changed to "battle fatigue", and clinical neuropsychology became even more involved with attempting to solve the puzzle of people's continued signs of trauma and distress. The
Veterans Administration, or VA, was created in 1930, which increased the call for clinical neuropsychologists and, by extension, the need for training. The
Korean and
Vietnam Wars further solidified the need for treatment by trained clinical neuropsychologists. In 1985, the term "
post-traumatic stress disorder", or PTSD, was coined, and the understanding that traumatic events of all kinds could cause PTSD started to evolve. The relationship between human behavior and the brain is the focus of clinical neuropsychology as defined by Meir in 1974. There are two subdivisions of clinical neuropsychology that draw much focus: organic and environmental natures.
Ralph M. Reitan,
Arthur L. Benton, and
A.R. Luria are all past neuropsychologists who believed in and studied the organic nature of clinical neuropsychology. Alexander Luria is the Russian neuropsychologist responsible for the origination of clinical psychoneurological assessment after WWII. Luria developed the 'combined motor method' to measure thought processes based on the reaction times when three simultaneous tasks are appointed that require a verbal response. On the other side, the environmental nature of clinical neuropsychology did not appear until more recently and is characterized by treatments such as behavior therapy. The relationship between physical brain abnormalities and the presentation of psychopathology is not completely understood but is one of the questions that clinical neuropsychologists hope to answer in time. In 1861, the debate over human potentiality versus localization began. The two sides argued over how human behavior is presented in the brain. Paul Broca postulated that cognitive problems could be caused by physical damage to specific parts of the brain based on a case study of his in which he found a lesion on the brain of a deceased patient who had presented the symptom of being unable to speak; that portion of the brain is now known as
Broca's area. In 1874, Carl Wernicke also made a similar observation in a case study involving a patient with a brain lesion who was unable to comprehend speech; the part of the brain with the lesion is now deemed
Wernicke's area. Both Broca and Wernicke believed in and studied the theory of localization. On the other hand, equal potentiality theorists believed that brain function was not based on a single piece of the brain but rather on the brain as a whole.
Marie J.P. Flourens conducted animal studies in which he found that the amount of brain tissue damaged directly affected the amount that behavior ability was altered or damaged.
Kurt Goldstein observed the same idea as Flourens except in veterans who had fought in World War I. In the end, despite all of the disagreement, neither theory completely explains the human brain's complexity.
Thomas Hughlings Jackson created a theory that was thought to be a possible solution. Jackson believed that both potentiality and localization were in part correct and that behavior was made by multiple parts of the brain working collectively to cause behaviors, and Luria furthered Jackson's theory. ==Career==