Cognitive dysfunctions in recreational and dependent cocaine users: role of attention-deficit hyperactivity disorder, craving and early age at onset

MSc, Lea M. Hulka, MSc, Katrin H. Preller, MSc, Daniela Jenni, MSc, Experimental and Clinical Pharmacopsychology, Department of Psychiatry, Psychotherapy and Psychosomatics, University Hospital of Psychiatry, University of Zurich, Switzerland
The British journal of psychiatry: the journal of mental science (Impact Factor: 7.34). 05/2013; 203(1). DOI: 10.1192/bjp.bp.112.118091
Source: PubMed

ABSTRACT BACKGROUND: Dependent cocaine users consistently display cognitive deficits but cognitive performance of recreational cocaine users has rarely been investigated. AIMS: To examine whether cognitive performance is impaired in relatively pure recreational and dependent cocaine users. METHOD: The cognitive performance of recreational (n = 68) and dependent cocaine users (n = 30) was compared with the performance of stimulant-naive controls (n = 68) employing an extensive neuropsychological test battery. Moreover, the impact of attention-deficit hyperactivity disorder (ADHD) symptoms, craving and early age at onset was analysed. RESULTS: Dependent cocaine users display broad cognitive impairments in the domains of attention, working memory, declarative memory and executive functions. The performance of recreational cocaine users in all four domains was intermediate between that of controls and dependent users and they displayed significant deficits foremost in the domains of attention and working memory. In addition, ADHD symptoms, craving and age at onset were important modulators of cognitive function in cocaine users. CONCLUSIONS: Cognitive deficits occur at a recreational and non-dependent level of cocaine use. Cocaine use and ADHD seem to have mutually aggravating effects on cognitive impairment.


Available from: Boris B Quednow, May 29, 2015
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: The use of alternative matrices such as oral fluid and hair has increased in the past decades because of advances in analytical technology. However, there are still many issues that need to be resolved. Standardized protocols of sample pretreatment are needed to link the detected concentrations to final conclusions. The development of suitable proficiency testing schemes is required. Finally, interpretation issues such as link to effect, adulteration, detection markers and thresholds will hamper the vast use of these matrices. Today, several niche areas apply these matrices with success, such as drugs and driving for oral fluid and drug-facilitated crimes for hair. Once those issues are resolved, the number of applications will markedly grow in the future.
    Bioanalysis 08/2014; 6(17):2193-209. DOI:10.4155/bio.14.194 · 3.03 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Cocaine addiction is a chronically relapsing disorder that is associated with harmful consequences. Relapses occur frequently and effective pharmacotherapies are currently sparse. Preclinical studies suggest that altered glutamatergic signaling is crucial for the maintenance of cocaine self-administration. However, the translational validity of these models is currently unknown. Therefore, we investigated potential differences of glutamate, glutamine and further metabolite levels in the pregenual anterior cingulate cortex (pgACC) and the right dorsolateral prefrontal cortex (rDLPFC) of chronic cocaine users and controls using the PRior knOwledge FITting 2.0 tool in combination with two-dimensional J-resolved single-voxel 1H-magnetic resonance spectroscopy at 3T and voxel tissue composition and relaxation correction. Glutamate and glutamine levels did not differ between cocaine users and controls, but higher weekly cocaine use and higher cocaine hair concentrations were associated with lower glutamine/creatine ratios in the pgACC. Interestingly, cocaine users exhibited higher glucose/total creatine ratios than controls in the pgACC and higher choline/creatine ratios in the pgACC and rDLPFC. These results imply that cocaine use is associated with altered cortical glucose metabolism and membrane turnover. Finally, cocaine use over the past 6 months appears to decrease cortical glutamine levels indicating changes in glutamate cycling.
    Addiction Biology 01/2015; DOI:10.1111/adb.12217 · 5.93 Impact Factor
  • Source
    [Show abstract] [Hide abstract]
    ABSTRACT: Human cognition relies on attentional capacities which, among others, are influenced by factors like tiredness or mood. Based on their inherent preferences in sleep and wakefulness, individuals can be classified as specific “chronotypes”. The present study investigated how early, intermediate and late chronotypes (EC, IC, LC) differ neurally on an attention-to-motion task. Twelve EC, 18 IC and 17 LC were included into the study. While undergoing functional magnetic resonance imaging (fMRI) scans, subjects looked at vertical bars in an attention-to-motion task. In the STATIONARY condition, subjects focused on a central fixation cross. During Fix-MOVING and Attend-MOVING, bars were moving horizontally. Only during the Attend-MOVING, subjects were required to attend to changes in the velocity of bars and indicate that by button presses. A two-way repeated measures ANOVA probed group by attentional load effects. The dorsolateral prefrontal cortex (DLPFC), insula and anterior cingulate cortex showed group by attention specific activations. Specifically, EC and LC presented attenuated DLPFC activation under high attentional load (Attend-MOVING), while EC showed less anterior insula activation than IC. LC compared to IC exhibited attenuation of superior parietal cortex. Our study reveals that individual sleep preferences are associated with characteristic brain activation in areas crucial for attention and bodily awareness. These results imply that considering sleep preferences in neuroimaging studies is crucial when administering cognitive tasks. Our study also has socio-economic implications. Task performance in non-optimal times of the day (e.g. shift workers), may result in cognitive impairments leading to e.g. increased error rates and slower reaction times.
    NeuroImage 02/2015; DOI:10.1016/j.neuroimage.2015.02.013 · 6.13 Impact Factor