ABSTRACT
Approximately 6 million youth aged 12 to 20 consume alcohol monthly in the United States. The effect of alcohol consumption in adolescence on behavior and cognition is heavily researched; however, little is known about how alcohol consumption in adolescence may alter brain function, leading to long-term developmental detriments. In order to investigate differences in brain connectivity associated with alcohol use in adolescents, brain networks were constructed using resting-state functional magnetic resonance imaging data collected by the National Consortium on Alcohol and NeuroDevelopment in Adolescence (NCANDA) from 698 youth (12-21 years; 117 hazardous drinkers and 581 no/low drinkers). Analyses assessed differences in brain network topology based on alcohol consumption in eight predefined brain networks, as well as in whole-brain connectivity. Within the central executive network (CEN), basal ganglia network (BGN), and sensorimotor network (SMN), no/low drinkers demonstrated stronger and more frequent connections between highly globally efficient nodes, with fewer and weaker connections between highly clustered nodes. Inverse results were observed within the dorsal attention network (DAN), visual network (VN), and frontotemporal network (FTN), with no/low drinkers demonstrating weaker connections between nodes with high efficiency and increased frequency of clustered nodes compared to hazardous drinkers. Cross-sectional results from this study show clear organizational differences between adolescents with no/low or hazardous alcohol use, suggesting that aberrant connectivity in these brain networks is associated with risky drinking behaviors.
ABSTRACT
BACKGROUND: "Craving" is a central concept in alcohol research, but the semantic interpretation of craving as a concept varies. Multiple studies that have investigated differences in operational definitions of craving have demonstrated a lack of agreement among them. This study investigated whether moderate to heavy drinkers would rate craving and "desire" for alcohol similarly and explored potential neurobiological differences underpinning feelings of craving and desire. METHODS: Thirty-nine individuals who consumed an average of at least 7 drinks/week for females and 14 drinks/week for males were studied across 3-day periods of their typical alcohol consumption and imposed abstinence. Ratings of desire and craving for alcohol were collected approximately every three hours during waking periods across the two experimental periods (n = 35, 17 males). At the end of each period, participants underwent functional MRI scanning during neutral and alcohol image viewing (n = 39, 17 males) followed by ratings of desire and craving for alcohol (n = 32, 16 males). Survey responses were analyzed using 2-level nested hierarchical modeling, image ratings were compared using a hierarchical mixed-effects regression, and brain networks constructed from fMRI data were assessed with a two-part mixed-effect regression (α = 0.05 in all analyses). RESULTS: Ratings of desire and craving differed significantly from one another in the survey data and in the ratings collected during image viewing. The strength of the desire experience was higher overall than craving, but the fluctuations over time were similar. Results for desire and craving differed on brain network attributes associated with distributed processing and those regional specific within the default mode network. Significant associations were found between ratings of desire and connection strength and between ratings of craving and connection probability. CONCLUSIONS: These results demonstrate that the difference between ratings of craving for alcohol and desire for alcohol is not trivial. The different ratings and their association with alcohol consumption or abstinence experiences may have significant biological and clinical implications.
ABSTRACT
Background: Stress is a motivator to consume alcohol, a well-documented relapse risk, and is known to differentially affect biological and psychological processes as people age.Objectives: Because alcohol consumption is known to acutely decrease stress and increase affect, this study examined differences in ratings of stress and affect in middle-aged versus younger adults who regularly consume alcohol.Methods: A sample of younger (n = 17) and middle-aged (n = 18) drinkers was studied during a 3-day period of typical alcohol consumption. Resting levels of respiratory sinus arrhythmia (RSA) were measured during a baseline study visit since RSA is a well-documented biomarker of stress and is known to decrease with age. Ecological momentary assessment (EMA) survey ratings (n = 1,598) were modeled using hierarchical regression to assess differences in stress and affect throughout the day between the two age groups.Results: As anticipated, middle-aged participants had lower RSA than those who were younger. Although the middle-aged adults showed overall lower stress, generally they also experienced higher affect than the younger adults. Middle-aged adults experienced a significant reduction in stress following drinking while no such effect was observed in the younger adults.Conclusions: To our knowledge, this is the first investigation using EMA methodology to examine stress and affect between younger and middle-aged adults who habitually consume alcohol. These cross-sectional data suggest potential momentary stress relief to engaging with moderate alcohol consumption in a middle-aged population. Future work must address this important motivational process in curtailing maintenance of alcohol consumption and preventing escalation of consumption.
