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Publication Abstract Display
Type: Published Abstract
Title: Comparison of the neurocognitive impact of alcohol and methamphetamine dependence.
Authors: Morgan E, Woods SP, Grant I, and the HNRP Group
Year: 2011
Publication: 34th Annual Research Society on Alcoholism Scientific Meeting, June 25th - 29th, Atlanta, Georgia
Volume: Issue: Pages:
Abstract:Alcohol and methamphetamine (MA) dependence each have been linked to brain injury, manifested by varying degrees of neurocognitive impairment (NCI). MA-related clinical manifestations such as disruption in attention, decision-making, prospective and episodic memory that may reflect mesocortical frontostriatal dysfunction appear to be linked to injury to dopinamergic circuitries, while motor impairments may be related to nigrostriatal effects. In alcoholism, executive disturbances and disruption of episodic memory also occur frequently, and other symptoms such as perceptual-motor effects are sometimes noted, perhaps reflecting a more generalized pattern of neural injury. The extent to which the neurocognitive effects of these two substances share common versus divergent features has not been explored closely. In the current study, an alcohol dependent group was directly compared to a MA dependent group and non-substance using controls on a battery of neuropsychological (NP) tests assessing multiple domains. The study sample comprised 38 alcohol dependent participants, 39 MA dependent participants without a history of alcohol dependence, and 51 non-substance abusing comparison subjects. A battery of NP tests, sampling 6 cognitive domains, was administered. Groups were compared on individual test scores, domain scores, and overall impairment. Results for overall NCI classification showed that 13.7% of controls were impaired, as compared to 26.3% of alcoholics, and 43.6% of the MA dependent (p = .006; only controls and MA significantly differed). Examination of test results in specific cognitive areas showed that both clinical groups were more impaired in motor function than controls, and the MA group was more likely to be impaired on attention/working memory (ps < 0.05); the alcohol but not MA dependent group performed worse than controls on a measure of executive function (p < 0.05). These results indicate that there may be both overlapping and separable patterns of impairment secondary to MA and alcohol. That is, the alcoholics had less global impairment than MA dependent, perhaps reflecting less extensive use of multiple substances. There is a suggestion of common impairing effects on motor function, but possibly differential effects in the areas of attention and working memory (stronger MA effect) and executive functioning (stronger alcohol effect). Due to small sample sizes, these inferences are tentative, awaiting larger scale confirmation.

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