You may not be as familiar with Karl Kahlbaum as you are with Emil Kraepelin, one of the most pivotal psychiatrists of his time who developed the modern classification of mental disorders.
But Kahlbaum paved the way for Kraepelin’s renowned work and also made some remarkable contributions of his own. In fact, Kahlbaum’s ideas — along with his assistant Ewald Hecker — influenced Kraepelin’s two major concepts: manic depression and dementia praecox (what we today call schizophrenia).
According to Richard Noll, associate professor of psychology at DeSales University, in his book American Madness: The Rise and Fall of Dementia Praecox, “What he produced would eventually revolutionize psychiatry once Kraepelin applied Kahlbaum’s concepts in Heidelberg [where Kraepelin lived and worked].”
Like Kraepelin, Kahlbaum was a German psychiatrist. Born in 1828 in Eastern Germany, Kahlbaum studied medicine at several universities: Königsberg, Würzburg and Leipzig. (He passed away in 1899.) After receiving his medical degree, working at a psychiatric clinic and teaching classes at Königsberg University, Kahlbaum began working at a private psychiatric hospital. He bought the hospital in 1867 and renamed the facility after himself (it was named for the previous owner).
According to The American Journal of Psychiatry:
…over the following 20 years he made it into an exemplary psychiatric hospital that became famous beyond German borders. He considered vocational therapy and arts and music therapy as an important part of psychiatric treatment. He regularly organized musical and theatrical performances for the patients in a room in his clinic that he designated for these purposes. Until 1943, the Kahlbaum Sanitarium was managed by one of his sons, Dr. Siegfried Kahlbaum.
In 1863 Kahlbaum published his book Gruppirung der psychischen Krankheiten und die Einteilung der Seelenstörungen (Classification of Psychiatric Diseases and Mental Disturbances). In it, he spelled out his own classification system.
Unfortunately, the psychiatric field couldn’t care less. According to Noll, the field largely ignored this work because Kahlbaum wasn’t a professor, and his classification system was in direct disagreement with Germany’s most popular paradigm: “unitary psychosis.”
At the time psychiatrists believed that there was one form of insanity, and the differences in symptoms were just stages along a continuum. Also problematic was that Kahlbaum’s classification system was “unnecessarily complex and the terms were unusual in construction,” Noll writes.
But bulky language and complexities aside, with this work, Kahlbaum contributed a key concept: time. Writes Noll in American Madness:
His revolutionary notion was that the only correct definitions of actual mental diseases would have to take into account their natural history of development. Cross-sectional descriptions of patients that were limited to a single time and place could no longer be regarded as valid. Didn’t the symptoms and behaviors of insane patients change over time? Of course they did. For Kahlbaum the most important elements were the period of life during which the symptoms first appeared (age of onset) and the typical ways the signs and symptoms changed over time.
Using this method meant more accurate diagnoses and some clues into the course and prognosis of mental disorders. Noll explains that it changed how case histories were written. In the 1900s, case histories started to include age of onset, alterations in symptoms and outcome.
Over the years, Kahlbaum and his assistant Hecker classified a very large collection of disorders. And some of these are still in use today, though Noll notes that the descriptions may be different from their originals. These include: catatonia, dysthymia, cyclothymia and hebephrenia.
Kahlbaum also contributed in other important ways. According to the same piece in The American Journal of Psychiatry:
He was the first to distinguish between psychoses with and without organic etiology. This dichotomous conceptualization of endogenous and organic mental disorders has proven heuristically fruitful for psychiatric classification since its inception.
In his understanding, psychiatric disorders consisted of a prodromal state, an acute state, a state of remission, and a state of convalescence. He had planned to make such “state-course entities” the basis of his classification of psychiatric disorders.