Longitudinal changes in cocaine intake and cognition are linked to cortical thickness adaptations in cocaine users

Abstract

BackgroundCocaine use has been consistently associated with decreased gray matter volumes in the prefrontal cortex. However, it is unclear if such neuroanatomical abnormalities depict either pre-existing vulnerability markers or drug-induced consequences. Thus, this longitudinal MRI study investigated neuroplasticity and cognitive changes in relation to altered cocaine intake.MethodsSurface-based morphometry, cocaine hair concentration, and cognitive performance were measured in 29 cocaine users (CU) and 38 matched controls at baseline and follow-up. Based on changes in hair cocaine concentration, CU were classified either as Decreasers (n = 15) or Sustained Users (n = 14). Surface-based morphometry measures did not include regional tissue volumes.ResultsAt baseline, CU displayed reduced cortical thickness (CT) in lateral frontal regions, and smaller cortical surface area (CSA) in the anterior cingulate cortex, compared to controls. In Decreasers, CT of the lateral frontal cortex increased whereas CT within the same regions tended to further decrease in Sustained Users. In contrast, no changes were found for CSA and subcortical structures. Changes in CT were linked to cognitive performance changes and amount of cocaine consumed over the study period.ConclusionsThese results suggest that frontal abnormalities in CU are partially drug-induced and can recover with decreased substance use. Moreover, recovery of frontal CT is accompanied by improved cognitive performance confirming that cognitive decline associated with cocaine use is potentially reversible.

Improvement of Emotional Empathy and Cluster B Personality Disorder Symptoms Associated With Decreased Cocaine Use Severity

“…The suggested consumption-dependent variability of social behavior as well as cluster B symptoms are well in line with our previous analyses from this sample that not only basal cognitive functions such as working memory but also self-reported impulsivity improve with a strong reduction of cocaine use, while they are worsened with increased cocaine consumption (7, 30). The present data and the previous analyses from this sample are also in accordance with our recent results from an independent longitudinal investigation showing that decreased cortical thickness (CT) of several regions within the prefrontal cortex of cocaine users can improve after a strong reduction of cocaine use, while sustained use went along with a further decrease in prefrontal CT during the study interval (63). Importantly, the cortical changes were correlated with cognitive changes, i.e., improved CT as associated with enhanced sustained attention (63).…”

Social and Non-Social Cognitive Enhancement in Cocaine Users—A Closer Look on Enhancement Motives for Cocaine Consumption

“…As our findings indicate that especially CU with comorbid ADHD employ PCE strategies and that cognitive impairments in CU with ADHD are amplified ( 41 ), we assume that substitution could be beneficial in these patients. We therefore suggest that attending physicians discuss putative PCE strategies and cognitive impairments with their patients in general, explain the negative long-term consequences of cocaine use ( 15 , 16 , 18 ) and additionally offer PCE with medical drugs as an alternative to CU with comorbid ADHD. This could foster treatment compliance as patients are signaled that their personal goals in using cocaine are respected and met.…”

“…Given these relatively broad cognitive deficits and the potential of cocaine to boost cognitive functions acutely (17), one might assume that at least some CU instrumentalize cocaine to self-medicate cognitive impairments that can be either preexisting or induced by chronic cocaine consumption (15,16,18). However, the association between cognitive impairment and pharmacological cognitive enhancement (PCE) with cocaine in CU has not been investigated yet.…”

Sensitivity to gains during risky decision-making differentiates chronic cocaine users from stimulant-naïve controls

“…Despite its negative consequences related with its use, cocaine remains one of the most commonly used illicit substances [13,14]. In addition to the immediate risk of overdose and intoxication, cocaine use represents a substantial burden for the individual and their families as for the society because of its associations with cardiovascular [15], neurological [10,[16][17][18], and psychiatric [19] disorders, as well as with cognitive deficits [20,21]. The negative consequences of cocaine use include not only decreases in quality of life and social functioning [3], but also an increase in high-risk behaviours and drug usage [11,22].…”

“…Moreover, chronic cocaine use is associated with neuroplastic adaptations in brain networks involved in executive functioning and risk-taking, as indicated by reduced cortical thickness in the lateral prefrontal cortex, anterior cingulate cortex, and orbitofrontal cortex [20,29,30]. Such alterations may partially explain why CU are more likely to make maladaptive decisions in situations requiring implicit learning about risks, and why they prefer up-front high gain at the cost of higher risk [31][32][33].…”