Using Neuroeconomics to Characterize State-Based Increases and Decreases in Alcohol Value

This study uses techniques from an area of research known as neuroeconomics, which integrates concepts and methods from psychology, neuroscience, and economics to better understand how people make decisions and how these decisions are supported by the brain. One neuroeconomic concept that is especially relevant in the area of addictions is substance demand, or how consumption of a commodity (e.g., alcohol, tobacco, or drugs) is influenced by price and other factors. Previous studies have shown that alcohol demand is related to severity of alcohol misuse, drinking quantity/frequency, and treatment outcomes. In addition, we know that alcohol demand can also fluctuate in response to environmental cues such as alcohol-related stimuli or external contingencies such as important responsibilities the following day. These increase and decreases in consumption and value are clinically significant because they help us understand how people with alcohol use disorders are able to successfully or unsuccessfully modulate their drinking behaviors. This study is examining how the brain responds in these situations and whether these responses differ as a function of severity of alcohol misuse. This study will use functional magnetic resonance imaging (fMRI) to understand brain activity patterns associated with changes in the value of alcohol in the presence of alcohol-related beverage cues relative to neutral-related beverage cue. Participants will be non-treatment-seeking adult heavy drinkers who are recruited from the community to participate in an fMRI scan. During the scan, participants will make decisions about how many alcohol beverages they would consume (hypothetically) at various prices while their brain activity during those decisions is measured. The first experimental manipulation involves an in-scanner alcohol cue exposure task in which the drinking decisions will be made after viewing high-quality images of alcoholic (beer/wine/liquor) beverages or neutral (water/juice/soft drinks) beverages.

Neuroeconomics integrates concepts and methods from psychology, economics, and cognitive neuroscience to understand the neurobiological foundations of decision making, and has been increasingly applied to understanding alcohol use disorder (AUD). A novel application of neuroeconomics is the study of alcohol demand, or the value of alcohol as measured by cost-benefit preferences. Alcohol demand paradigms have considerable ecological validity by measuring the impact of internal and external influences on alcohol decision-making, such as price, environmental cues, affective states, or external contingencies. Behaviorally, alcohol demand is elevated among individuals with higher levels of alcohol misuse and predicts treatment response. Alcohol demand also exhibits state-like properties, including increases following exposure to alcohol-related cues. The overall goal of the proposed studies is to characterize the neural activity that subserves these established behavioral findings using a novel functional MRI paradigm. The primary aim is to examine the patterns of neural activation underlying increases in the value of alcohol in response to alcohol cues. To do so, the first study will use a within-subjects design to identify differences in neural activity associated with demand decisions following a validated in-scanner cue exposure protocol consisting of exposure to neutral beverage cues and exposure to alcohol beverage cues in a sample of adult heavy drinkers. Using a novel neuroeconomics approach, this study combines a highly ecologically-valid alcohol demand paradigm with two experimental manipulations that model clinically-relevant influences on drinking decisions. Studying these contextual influences may help clarify the neural signatures that underlie drinking moderation vs. unconstrained drinking, and how these processes are impacted by AUD. If successful, these studies will provide a foundation for examining neural predictors of successful recovery or response to treatment vs. relapse. More broadly, findings from this study have high potential to significantly enhance the clinical relevance of alcohol neuroscience.

Participants will undergo a validated cue exposure protocol involving exposure to neutral beverage cues followed by exposure to alcohol beverage cues

Participants will undergo a validated in-scanner alcohol cue exposure protocol involving passive viewing of images of alcohol beverages (beer, wine, or liquor)

Participants will undergo a validated in-scanner alcohol cue exposure protocol involving passive viewing of images of neutral beverages (water).

Participants will report how many standard drinks they would consume at varying prices using a hypothetical Alcohol Purchase Task (APT) procedure. The APT is a validated self-report measure of alcohol consumption (in standard drink units) at escalating prices (18 price intervals, ranging from $0 to $80/drink). Responses on APT are analyzed to generate observed and derived indices of alcohol demand, including: intensity (consumption at free price); breakpoint (maximum price for spent for a single drink); Omax (maximum expenditure on alcohol); and Elasticity (proportionate slope of the alcohol demand curve)

Self-reported subjective ratings of craving and urge for alcohol using a 100-point visual analogue scale, from 0 (no urge/craving for alcohol) to 100 (maximum urge/craving for alcohol)

Self-reported subjective ratings of positive and negative affect, using 10-point visual analogue scales assessing the following affect dimensions: happy, sad, bored, stressed, and relaxed

Inclusion Criteria: 21-55 years old; Right-handed; Fluent English speaker; Heavy drinker (i.e., on average > 14/7 drinks per week for males/females in past three months; Average of 1 heavy drinking episode weekly (heavy drinking episode = 5+/4+ for males/females) over past three months Exclusion Criteria: Currently receiving treatment, or seeking treatment, for alcohol related problems; Current Diagnostic and Statistical Manual (DSM-5) substance use disorder other than alcohol or tobacco; Weekly or more frequent use of recreational drugs; History of schizophrenia-spectrum disorders, psychotic disorders, bipolar disorder, or PTSD; History of neurocognitive disorder or impairment; MRI contraindications (e.g., metal in body, history of seizure, etc.); History of serious brain injury; Currently taking psychotropic medications or medications that could affect cerebral blood flow; Pregnancy (females); Attending any study session with a positive breath alcohol concentration (BrAC > 0.00g%)