Disrupted Resting State Attentional Network Connectivity in Adolescent and Young Adult Cannabis Users following Two-Weeks of Monitored Abstinence

Abstract

Background. Numerous neuropsychological studies have shown that cannabis use during adolescence and young adulthood led to deficits in sustained and selective attention. However, few studies have examined functional connectivity in attentional networks among young cannabis users, nor have characterized relationships with cannabis use patterns following abstinence. Methods. Differences in resting state functional connectivity (RSFC) within the dorsal (DAN) and ventral (VAN) attention networks were examined in 36 adolescent and young adult cannabis users and 39 non-substance using controls following two weeks of monitored abstinence. Observed connectivity differences were then correlated with past-year and lifetime cannabis use, length of abstinence, age of regular use onset, and Cannabis Use Disorder symptoms (CUD). Results. After controlling for alcohol and nicotine use, cannabis users had lower RSFC within the DAN network, specifically between right inferior parietal sulcus and right anterior insula, as well as white matter, relative to controls. This region was associated with more severe cannabis use measures, including increased lifetime cannabis use, shorter length of abstinence, and more severe CUD symptoms. Conclusions. Findings demonstrate that regular cannabis use by adolescents and young adults is associated with subtle differences in resting state connectivity within the DAN, even after two weeks of monitored abstinence. Notably, more severe cannabis use markers (greater lifetime use, CUD symptoms, and shorter abstinence) were linked with this reduced connectivity. Thus, findings support public policy aimed at reducing and delaying cannabis use and treatments to assist with sustained abstinence. Future longitudinal studies are needed to investigate causation.

The effects of cannabis abstinence on cognition and resting state network activity in people with multiple sclerosis: A preliminary study

“…Comparisons are hindered by few studies and samples limited to adolescents and young adults. A study following adolescent and young adults who were regular cannabis users revealed abnormal connectivity within the dorsal and attentional network, even after two weeks of monitored abstinence ( Harris et al, 2022 ). Another study in a sample of adults between the ages of 16–26 years who were regular cannabis users, revealed weaker connectivity between the left posterior cingulate cortex and various DMN nodes when compared to a matched group of non-cannabis users ( Ritchay et al, 2021 ).…”

Neural substrates of substance use disorders

“…The differences in other parts of the brain are more variable and depend on the type of construct that is being examined. Comparing individuals with cannabis user disorder relative to comparison individuals, researchers found lower resting-state functional connectivity within the dorsal attention network, which was associated with more severe cannabis use measures, including increased lifetime cannabis use, shorter length of abstinence and more severe cannabis use disorder symptoms [8]. On the one hand, in participants with heroin use disorder, there appears to be a marked decrease in resting-state functional connectivity between interhemispheric dorsolateral prefrontal cortex [9].…”