Neurocognitive Characteristics of Individuals With Schizophrenia and Cocaine Dependence (original) (raw)

Neuropsychological functioning and age-related changes in schizophrenia and/or cocaine dependence

2013

Although little is known about the combined effects of Schizophrenia (SZ) and Substance Use Dependence (SUD) in neurocognitive functioning, the current literature points out that performance depends on the specific cognitive domains, the age of individuals and the type of substance of abuse. Our aim is to elucidate, in a sample with SZ and/or cocaine dependent individuals in remission for more than 4 months, their performance in attention, verbal memory and speed of processing, taking into account the possible effect of both age and duration of SUD. The total sample consisted of 95 male patients, aged 20 to 60 years, divided in three groups: one group with SZ and cocaine dependence (SZ+), another group with SZ without cocaine dependence (SZ−) and a third group with cocaine dependence without psychiatric comorbidity (COC). Our results show that those SZ+ who were abstinent for more than four months did not differ from their SZ− counterparts in the neuropsychological functioning. Both SZ groups performed significantly worse than the COC group. A negative impact of age on the neuropsychological performance was found in the SZ+ group, suggesting additive later cognitive deficits in SZ+ patients due to the long-term brain damage of SUD.

Executive functioning in individuals with schizophrenia and/or cocaine dependence

Human Psychopharmacology: Clinical and Experimental, 2013

Objective Although little is known about neurocognition in Dual Diagnosis, it has been suggested that Schizophrenia (SZ) patients with comorbid substance use belong to a subgroup with lower genetic vulnerability to develop SZ and, consequently, they show better executive and social premorbid functioning. The first aim of this study was to assess the executive functioning, and the second one was to explore the effect of age of onset of substance use in neurocognition in SZ patients with cocaine dependence. Methods The total sample consisted of 95 male patients, aged 20 to 60 years, divided in three groups: one group with SZ and cocaine dependence (SZ+; n = 30), another group with SZ without cocaine dependence (SZÀ; n = 30), and a control group with cocaine dependence without psychiatric comorbidity (COC; n = 35). Results We found a better executive functioning in both SZ+ and COC than SZÀ. We observed a worse performance of SZ+ patients compared with COC in cognitive set-shifting regardless the age of onset of consumption. Conclusions The results agree with the hypothesis of a lower genetic vulnerability in SZ+ patients to develop psychosis compared with SZÀ, who develop it without any additional trigger. However, future research is needed to clarify the current knowledge gaps. Copyright

Neurocognitive functioning in recently abstinent, cocaine-abusing schizophrenic patients

Journal of substance abuse, 2000

This report examined a broad range of cognitive functioning in a group of recently abstinent, cocaine-abusing schizophrenic patients (CA + SZ). Measures of selective and sustained attention, learning and memory, and executive functioning were administered to CA + SZ patients within 72 h of last cocaine use. A comparison group of non-substance-abusing schizophrenic patients (SZ) presenting for inpatient psychiatric treatment were also examined in an identical time frame. We hypothesized that the neurobiological impact of cocaine abuse and acute abstinence would cause CA + SZ to manifest deficits in all domains of cognitive functioning relative to non-abusing SZ patients. Results revealed that CA + SZ displayed significant memory impairment relative to their non-abuser SZ counterparts. No group differences, however, were detected on any other neurocognitive measure. CA + SZ were able to selectively process digit strings during the presence and absence of distracting stimuli, sustain a...

The Neuropsychology of Cocaine Addiction: Recent Cocaine Use Masks Impairment

Neuropsychopharmacology, 2009

Individuals with current cocaine use disorders (CUD) form a heterogeneous group, making sensitive neuropsychological (NP) comparisons with healthy individuals difficult. The current study examined the effects on NP functioning of four factors that commonly vary among CUD: urine status for cocaine (positive vs negative on study day), cigarette smoking, alcohol consumption, and dysphoria. Sixty-four cocaine abusers were matched to healthy comparison subjects on gender and race; the groups also did not differ in measures of general intellectual functioning. All subjects were administered an extensive NP battery measuring attention, executive function, memory, facial and emotion recognition, and motor function. Compared with healthy control subjects, CUD exhibited performance deficits on tasks of attention, executive function, and verbal memory (within one standard deviation of controls). Although CUD with positive urine status, who had higher frequency and more recent cocaine use, reported greater symptoms of dysphoria, these cognitive deficits were most pronounced in the CUD with negative urine status. Cigarette smoking, frequency of alcohol consumption, and dysphoria did not alter these results. The current findings replicate a previously reported statistically significant, but relatively mild NP impairment in CUD as compared with matched healthy control individuals and further suggest that frequent/recent cocaine may mask underlying cognitive (but not mood) disturbances. These results call for development of pharmacological agents targeted to enhance cognition, without negatively impacting mood in individuals addicted to cocaine.

Neuropsychological effects associated with recreational cocaine use

Psychopharmacology, 2012

RATIONALE: Recent evidence suggests that recreational cocaine use is on the increase, with the UK reporting one of the highest levels of use in the EU (EMCDDA 2010). Nevertheless, very few studies have addressed the neuropsychological effects associated with non-dependent recreational cocaine use. OBJECTIVES: The current study aimed to assess whether recreational cocaine users show neuropsychological deficits on a battery of tests, previously shown to be sensitive to cocaine-dependent and psychosis-prone individuals. Schizotypal traits were also measured. METHODS: Recreational cocaine users (n = 17) were compared with controls (n = 24) on drug use patterns, the General Health Questionnaire, the Brief Schizotypal Personality Questionnaire (SPQ-B) and four neuropsychological tasks: spatial working memory, intra/extra-dimensional set shifting, the Stocking of Cambridge and the rapid visual processing. RESULTS: Relative to controls, recreational cocaine users produced significantly more...

Neuropsychological deficits in chronic cocaine abusers

1991

A basic neuropsychological assessment battery was given to thirty-seven chronic freebase cocaine ("crack") abusers. The following tests were used: Wechsler Memory Scale , Rey-Osterrieth Complex Osterrieth, 1944) (copy and immediate reproduction), Verbal Fluency (semantic and phonologic), Boston Naming Test (Goodglass, Kaplan, & Weintrab, 1983), Wisconsin Card Sorting Test (Heaton, 198 I ) and Digit-symbol from the WISC (Wechsler, 1974). In general, performance was lower than expected according to their age and cductational level. Subjects showed significant impairment in short-term verbal memory and attention subtests. Neuropsychological test scores were correlated with lifetime amount of cocaine used, suggesting a direct relationship between cocaine abuse and cognitive impairment. A pattern of cognitive decline is proposed.

381. Neurocognitive deficits in cocaine abusing schizophrenic patients

Biological Psychiatry, 1998

BIOLPSYCHIATRY 1998;43:1S-133S Saturday Abstracts on line (maintenance),and use of the remember~stimuli to guide response (output).In the present study, a delayedmatchingto sample task was developedin which difficulty for each subject was equated at zero delay, so as to isolate the effects of maintenancewhen delay was added on subsequenttrials. Participants were 48 patients in the first episode of schizophreniaand 21 healthy comparison subjects. Stimuliconsistedof 9x9grids of pixels,41 of whichwere illuminated, formingcomplexpatterns. Each trial consistedof one target stimulus followedby two test stimuli, one of whichwas identical to the target. Item difficultywas measuredby the percentageof pixels identical for the two target stimuli. In phase I, test stimuli were presented immediately after the target (zero delay), and item difficulty was titrated until each subject achieved a consistent accuracy between 80% and 90%. In phase II, a delay of 4 or 8 secondswith a mask of randomly illuminated pixels was introducedbetween target and test stimuli; item difficulty was set at the level determined in phase L Comparedto healthy subjects, patients attained a significantlylower level of difficulty in phase I. While all subjects showed diminished accuracyin phaseII, patients showedsignificantlyworseperformance with delay comparedto controls.Results indicate that WM deficits in schizophrenia exist even when subjects are matched on initial stimulus processing.

Neurocognitive Functioning of Individuals With Schizophrenia: Using and Not Using Drugs

Schizophrenia Bulletin, 2013

Objectives: Research on neurocognition in schizophrenia, using modest samples and self-rated assessments, reports drug use contributes to improved rather than impaired cognitive function. We have sought to replicate these findings in a large sample of patients that had their drug-use status confirmed by laboratory assays and evaluated the potential differences in cognitive function between patients with positive and negative results. Methods: Nine hundred and seventy four schizophrenia patients completed neuropsychological and laboratory tests at screening/baseline of the Clinical Antipsychotic Trials of Intervention Effectiveness study. Radioimmunoassay (RIA) of hair tested for cannabis, cocaine and methamphetamine. Results: Many patients screened positive for drug use (n = 262; 27%), and there were no differences between patients with positive and negative results in terms of cognitive function after adjusting for multiple inference testing, except patients with positive RIA for methamphetamine demonstrated increased processing speed (corrected, P = .024). Moderator models were employed to explore potential subgroup differences in this pattern of results. At low medication dosages, patients with positive RIA for cocaine demonstrated decreased processing speed compared with patients with negative RIA for cocaine (uncorrected, P = .008). And for any other drugs with low psychopathology, patients with positive RIA demonstrated decreased working memory compared with patients with negative RIA (uncorrected, P = .006). Conclusions: No positive effects of cannabis on cognitive function were observed, and drug use was not associated with improved neurocognition across most of the subgroup characteristics explored in this sample of schizophrenia patients.