Ji. Tracy et al., NEUROPSYCHOLOGY OF DUAL DIAGNOSIS - UNDERSTANDING THE COMBINED EFFECTS OF SCHIZOPHRENIA AND SUBSTANCE USE DISORDERS, Clinical psychology review, 15(2), 1995, pp. 67-97
Empirical studies of cognitive functioning in patients suffering from
schizophrenia and a substance use disorder are lacking Consensus exist
s that schizophrenia is a neurobehavioral disorder with cognitive defi
cits. With this ready explanation for cognitive impairment in schizoph
renia, there exists the possibility that other treatable sources of co
gnitive decline in schizophrenia, such as substance abase, may be igno
red. The cognitive impairments (e.g., abstraction, selective attention
, effortful processing episodic memory and denial of deficits/illness)
and biologic abnormalities (e.g., reduced P300 amplitude, enlarged ve
ntricles, and hypofrontality) common to both schizophrenia and substan
ce use disorders are reviewed. Differences in the cognitive status of
the disorders are also noted. Factors altering the cognitive status of
these patients are discussed, and seven potential frameworks are offe
red for conceptualizing the etiologic relation and cognitive impact of
these disorders.