Cerebral Metabolic Dysfunction and Impaired Vigilance in Recently Abstinent Methamphetamine Abusers

Department of Psychiatry and Biobehavioral Sciences, David Geffen School of Medicine, University of California Los Angeles, Los Angeles, California 90024-1759, USA.
Biological Psychiatry (Impact Factor: 10.26). 12/2005; 58(10):770-8. DOI: 10.1016/j.biopsych.2005.04.039
Source: PubMed


Methamphetamine (MA) abusers have cognitive deficits, abnormal metabolic activity and structural deficits in limbic and paralimbic cortices, and reduced hippocampal volume. The links between cognitive impairment and these cerebral abnormalities are not established.
We assessed cerebral glucose metabolism with [F-18]fluorodeoxyglucose positron emission tomography in 17 abstinent (4 to 7 days) methamphetamine users and 16 control subjects performing an auditory vigilance task and obtained structural magnetic resonance brain scans. Regional brain radioactivity served as a marker for relative glucose metabolism. Error rates on the task were related to regional radioactivity and hippocampal morphology.
Methamphetamine users had higher error rates than control subjects on the vigilance task. The groups showed different relationships between error rates and relative activity in the anterior and middle cingulate gyrus and the insula. Whereas the MA user group showed negative correlations involving these regions, the control group showed positive correlations involving the cingulate cortex. Across groups, hippocampal metabolic and structural measures were negatively correlated with error rates.
Dysfunction in the cingulate and insular cortices of recently abstinent MA abusers contribute to impaired vigilance and other cognitive functions requiring sustained attention. Hippocampal integrity predicts task performance in methamphetamine users as well as control subjects.

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Available from: Bradley Voytek, Oct 07, 2015
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    • "While few other studies have examined relationships between denial and the brain in addiction, the cortical and limbic regions identified in the current study have been variously associated with other abnormalities in methamphetamine users. Compared to healthy control subjects, methamphetamine-dependent participants have exhibited hypoactivity of the ACC associated with inhibitory control deficits (Nestor et al., 2011), increase in cerebral glucose metabolism in the precuneus during early abstinence (Berman et al., 2007), gray matter deficits in the ACC, OFC, precuneus, amygdala and hippocampus (Morales et al., 2012; Thompson et al., 2004), and aberrant relative glucose metabolism in the ACC, OFC and amygdala associated with inattention and mood disturbances (London et al., 2004, 2005). Future studies are needed to investigate mechanisms by which these abnormalities may, in isolation or combination, contribute to reduced insight/denial. "
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    • "Individuals with substance use disorders are at risk for numerous cognitive deficits resulting from excessive substance use, including poorer memory functioning (Glass, et al., 2009; Javanovski, Erb, & Zakzanis, 2005; London et al., 2005; Scott, Woods, Matt, Meyer, Heaton, & "
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    • "varenicline and nicotine). Whereas previous studies have noted between-group differences in error-related brain activity when comparing non-drug using controls with cocaine (Kaufman et al. 2003), methamphetamine (London et al. 2005), opiate (Forman et al. 2004), cannabis (Hester et al. 2009) and nicotine abusers (Luijten et al. 2011), our results suggest that within-group variations in externalizing traits account for additional variability in brain measures. Elucidating such individual variations may prove beneficial for facilitating the implementation of individualized treatment regimens. "
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