A NEUROPSYCHOLOGICAL PERSPECTIVE ON DUAL DIAGNOSIS

The purpose of this study was to investigate whether patients experien cing both a major psychiatric disorder and a concurrent substance abus e problem (dual diagnosis) manifest greater neuropsychological dysfunc tions than patients experiencing a major psychiatric disorder alone. D ifferences in diagnostic variability and fluidity between dual diagnos is and non-dual diagnosis patients and the occurrence of polysubstance abuse among the dual diagnosis patients were also investigated. The h ypotheses were tested by retrospectively reviewing the psychiatric rec ords of 50 dual diagnosis patients and comparing them to 36 chronicall y hospitalized non-dual diagnosis psychiatric patients. Results reveal ed that dual diagnosis patients manifested significantly greater neuro psychological impairments than non-dual diagnosis patients and that du al diagnosis patients showed a greater range of diagnoses and diagnosi s fluidity than non-dual diagnosis patients. Results also revealed tha t over one-half of the dual diagnosis patients abused a variety of dif ferent substances. An etiological role of neuropsychological dysfuncti on in the development of the dual diagnosis syndrome in at least a sub group of dual diagnosis patients is suggested. More specifically, it i s suggested that the neuropsychological dysfunctional pattern that is described may represent an organic substrate of a nonspecific vulnerab ility to developing both (atypical) psychoses and (poly) substance abu se.