Cognitive Performance by Humans During a Smoked Cocaine Binge-Abstinence Cycle

Abstract

Five cocaine-dependent individuals completed a 22-day inpatient study of sleep and cognition. Following 3 days of drug-free baseline, participants underwent 3 days of twice-daily smoked cocaine base self-administration (6 50-mg doses, 14 minutes apart), followed by 15 days of abstinence. Each morning and afternoon, the CDR repeatable, multiple-version, computerized cognitive battery (whose stability following practice has been documented) was administered. During abstinence, performance deteriorated on vigilance tasks (especially reaction time) as well as on immediate and delayed verbal recognition tasks but not on working memory tasks. Declines were most evident in the afternoon. Data suggest that abstinence can unmask cognitive deficits induced by chronic cocaine use and circadian factors may mediate their severity.

Differential effects of self-administered cocaine in adolescent and adult rats on stimulus–reward learning

“…Together, these findings suggest that a deficit in stimulus-reward learning develops when cocaine is onboard and persists for at least 18 days after cocaine access is terminated in adult rats. Long-term dysfunction of the amygdala memory system after cocaine self-administration in adult male rats is consistent with the clinical literature showing that cocaine addicts display neurocognitive deficits in a number of domains (e.g., attention, working memory, decision making, spatial memory, verbal memory) after recent drug use and after several months of cocaine abstinence (Strickland et al 1993;Bolla et al 1999Bolla et al , 2003Grant et al 2000;Di Sclafani et al 2002;Simon et al 2002;Pace-Schott et al 2005).…”

“…This task requires the intact functioning of the amygdala memory system for acquisition and expression of stimulus-reward learning (McDonald and White 1993;Kantak et al 2001). As clinical studies typically assess neurocognitive functioning of adult cocaine addicts during a forced or self-imposed abstinence period (Bolla et al 1999(Bolla et al , 2003Grant et al 2000;Di Sclafani et al 2002;Simon et al 2002;Pace-Schott et al 2005), using an experimental design that incorporates a drug-free period is relevant from a translational perspective and extends our earlier work in adult rats tested under the influence of cocaine (Udo et al 2004;Kantak et al 2005).…”

Widespread disruption in brain activation patterns to a working memory task during cocaine abstinence

“…Cocaine abstinence is associated with impaired performance in cognitive functions including attention, vigilance and executive function (Goldstein R et al, 2004;Kelley B et al, 2005;Pace-Schott E et al, 2005) and imaging studies of cocaine abusers tested during abstinence have reported reduced DA activity (Volkow ND et al, 1997). A limitation of our study is that even though we ascribe the differences between groups to cocaine abstinence we cannot rule out the contribution of nicotine withdrawal since the groups differed in their smoking histories and nicotine withdrawal is associated with cognitive impairment (Giannakoulas G et al, 2003;Shoaib M and L Bizarro, 2005).…”

“…Cocaine abuse is associated with disruption in cognitive operations that include attention, executive function, and vigilance (Goldstein R et al, 2004;Pace-Schott E et al, 2005). Imaging studies of cocaine abusers tested during abstinence and protracted detoxification have reported reduced dopamine (DA) activity (Volkow ND et al, 1997), which has been linked with long lasting decreases in activity of frontal cortical regions [i.e., dorsolateral prefrontal cortex (DLPFC), anterior cingulate gyrus (ACG) and orbitofrontal cortex] (Volkow N et al, 2001).…”

Cocaine Users Differ from Normals on Cognitive Tasks Which Show Poorer Performance During Drug Abstinence

“…In chronic cocaine users studied under controlled inpatient conditions (7)(8)(9) we have shown that performance on tests of sustained attention and recognition memory (7) or sustained attention alone (9), but not working memory, was poorer during abstinence than during days on which cocaine was used. We here compare previously reported performance of cocainedependent individuals (7,9) to population norms.…”