Abstract
Background—Determining the brain-behavior profiles that differentiate heavy drinkers who are and are not alcohol dependent will inform treatment efforts. Working memory is linked to substance use disorders and can serve as a representation of the demand placed on the neurophysiology associated with cognitive control.
Methods—Behavior and brain activity (via fMRI) were recorded during an N-Back working memory task in controls (CTRL), nondependent heavy drinkers (A-ND) and dependent heavy drinkers (A-D). Typical and novel step-wise analyses examined profiles of working memory load and increasing task demand, respectively.
Results—Performance was significantly decreased in A-D during high working memory load (2-Back), compared to CTRL and A-ND. Analysis of brain activity during high load (0-Back vs. 2-Back) showed greater responses in the dorsal lateral and medial prefrontal cortices of A-D than CTRL, suggesting increased but failed compensation. The step-wise analysis revealed that the transition to Low Demand (0-Back to 1-Back) was associated with robust increases and decreases in cognitive control and default-mode brain regions, respectively, in A-D and A-ND but not CTRL. The transition to High Demand (1-Back to 2-Back) resulted in additional engagement of these networks in A-ND and CTRL, but not A-D.
Conclusion—Heavy drinkers engaged working memory neural networks at lower demand than controls. As demand increased, nondependent heavy drinkers maintained control performance but relied on additional neurophysiological resources, and dependent heavy drinkers did not display further resource engagement and had poorer performance. These results support targeting these brain areas for treatment interventions.
Document Type
Article
Publication Date
6-1-2017
Digital Object Identifier (DOI)
https://doi.org/10.1016/j.drugalcdep.2017.01.029
Funding Information
This work was supported by National Institute of Drug Abuse [grant numbers DA007246, DA031766, DA020074, and DA06634].
Related Content
Refer to Web version on PubMed Central for supplementary material.
Repository Citation
Wesley, Michael J.; Lile, Joshua A.; Fillmore, Mark T.; and Porrino, Linda J., "Neurophysiological Capacity in a Working Memory Task Differentiates Dependent from Nondependent Heavy Drinkers and Controls" (2017). Behavioral Science Faculty Publications. 40.
https://uknowledge.uky.edu/behavsci_facpub/40
Supplementary File 1.
NIHMS861837-supplement-2.pdf (47 kB)
Supplementary File 2.
NIHMS861837-supplement-3.pdf (1588 kB)
Supplementary File 3.
NIHMS861837-supplement-4.pdf (729 kB)
Supplementary File 4.
Included in
Behavior and Behavior Mechanisms Commons, Psychology Commons, Substance Abuse and Addiction Commons
Notes/Citation Information
Published in Drug and Alcohol Dependence, v. 175, p. 24-35.
© 2017 Elsevier B.V. All rights reserved.
This manuscript version is made available under the CC‐BY‐NC‐ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/.
The document available for download is the author's post-peer-review final draft of the article.