Intoxicated with Madness: Exploring the Psychology of Intoxication in Uncovering the Experimental Roots of the Kraepelinian Dichotomy

11/08/2026

AI Summary

Kraepelin's experimental psychology of intoxication contributed latent, synthesising concepts that shaped his twofold nosology of dementia praecox and manic-depressive illness.
Comparative analysis across six textbook editions links Kraepelin's experimental findings on intoxication to the organisation of clinical diagnostic descriptions.
Inhibitory and excitatory effects in sensation and perception map onto his duality: dementia praecox as inhibitory mode, manic-depression as excitatory mode of exogenous psychosis.

AI Summary

Scholarship surrounding the Kraepelinian dichotomy of dementia praecox and manic-depressive insanity has overwhelmingly approached Kraepelin's nosology as the product of Kraepelin's clinical method, use of diagnostic cards, and pre-existing disease concepts, rather than his work in experimental psychology.

Revisiting the significance of Kraepelin's 1881-1895 concept of intoxication as model psychosis, this article establishes that Kraepelin's earlier psychological experiments with intoxicants were a potential source of latent, synthesizing concepts, informing the organization of clinical data around two discrete forms of psychosis.

Tracking Kraepelin's nosological system over the course of the first six editions of his textbook, it examines Kraepelin's classificatory descriptions relative to the content of his experimental studies on the psychometrics of intoxication, in particular the dualities Kraepelin finds in exogenous and endogenous psychoses.

Basic summary

Transcult Psychiatry. 2026 Aug 11:13634615261471986. doi: 10.1177/13634615261471986. Online ahead of print.

ABSTRACT

Scholarship surrounding the Kraepelinian dichotomy of dementia praecox and manic-depressive insanity has overwhelmingly approached Kraepelin’s nosology as the product of Kraepelin’s clinical method, use of diagnostic cards, and pre-existing disease concepts, rather than his work in experimental psychology. Revisiting the significance of Kraepelin’s 1881-1895 concept of intoxication as model psychosis, this article establishes that Kraepelin’s earlier psychological experiments with intoxicants were a potential source of latent, synthesizing concepts, informing the organization of clinical data around two discrete forms of psychosis. Tracking Kraepelin’s nosological system over the course of the first six editions of his textbook, it examines Kraepelin’s classificatory descriptions relative to the content of his experimental studies on the psychometrics of intoxication, in particular the dualities Kraepelin finds in exogenous and endogenous psychoses. More specifically, it addresses the alignment of inhibitory and excitatory effects at the level of sensation and perception found within both Kraepelin’s experiments and psychiatric nosology, proposing that manic-depression and dementia praecox conform with excitatory and inhibitory modes of exogenous psychosis.

PMID:42578824 | DOI:10.1177/13634615261471986

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