Thomas A. Ban and Marelo Cetkovich-Bakmas: Carl Wernicke’s Elementary Syptoms and Sejunction Hypothesis

Thomas A. Ban: Collated Document


Ernst Franzek’s final comment


         It’s a great pleasure for me to congratulate Marcelo Cetkovich-Bakmas and Hector Warnes for their outstanding descriptions and comments on Wernicke’s theory of “sejunction” as one of the main common morphological processes in psychiatric diseases.

         According to Wernicke, the process of “sejunction” explains “acute” elementary symptoms, for  example hallucinations, as well as all kinds of chronic residual psychopathology (Wernicke, 1900; Franzek, 1990) that occur in the course of psychiatric diseases.

         Wernicke’s psychiatric theories are mostly discussed in a historical context. However, modern neural science teaches us very well about the complex network and connectivity of neurons in the human brain (Principals of neural science, 2013).

         The great impact of the brains' capability of creating and keeping synapses (connections) between different neurons and brain regions is necessary for a normal functioning of the (adult) brain. Synaptic connections are made by sensory experiences, thought processes and psychomotor activity. Loss of synapses, in cortical and/or subcortical regions, causes loss of connectivity between functional brain circuits and could be postulated to be the not yet detected substrate of Wernicke’s “sejunction” in the brain of psychiatrically ill patients.

         It is strongly recommended to investigate Wernicke’s “sejunction” theory with modern neural scientific methodologies. A loss of synaptic connectivity in specific brain regions and specific functional brain systems which can completely or partially regenerate, but which also can remain permanent or can be reconnected falsely, could explain acute and chronic psychopathology of psychiatric diseases.

         The different clinical psychopathology would then depend on the different functional brain circuits that are involved in the process of “sejunction.” The onset and ongoing process of “sejunction” (disconnection) could be triggered by genetic disposition, by stress exposure and/or by other adverse noxious events occurring during lifetime.

         It is strongly suggested that Wernicke’s theory of “sejunction” is not only of historical interest, but is still actual and of great value in the light of modern neural science and clinical research.





Franzek E. Influence of Carl Wernicke on Leonhard’s nosology. Psychopathology 1990; 23:277-81.


Kandel ER, Schwartz JH, Siegelbaum SA, Hudspeth AJ. (eds.) Principles of Neural Science. 5th edition, Mc Graw Hill Medical, New York/Chicago/San Francisco/Lisbon/London/Madrid/ Mexico City/ Milan/ New Delhi/ San Juan/ Seoul/ Singapore/ Sydney/ Toronto: Mc Graw Hill Medical; 2013.


Wernicke C. Grundriss der Psychiatrie in klinischen Vorlesungen. Barth: Leipzig; 1900.


Ernst J. Franzek