Anita Cservenka

Risky decision-making: An fMRI study of youth at high risk for alcoholism

BACKGROUND Adolescents with a family history of alcoholism (FHP) are at risk for developing an alcohol use disorder (AUD), and some studies indicate that FHP individuals show deficits in executive functioning. The ability to make adaptive decisions is one aspect of successful executive functioning that is often measured during risk-taking tasks; however, this behavior has not been examined in FHP youth. As impaired decision-making could predispose FHP youth to make poor choices related to alcohol use, the current study examined the neural substrates of risk-taking in FHP adolescents and their family history negative (FHN) peers. METHODS Thirty-one (18 FHP, 13 FHN) youth between 13 and 15 years old were included in this study. All youth had used little to no alcohol prior to study involvement. Functional magnetic resonance imaging was used to examine the neural substrates of risk-taking during the Wheel of Fortune (WOF) decision-making task (Ernst et al., 2004) in FHP and FHN youth. RESULTS FHP youth did not differ from FHN youth in risk-taking behavior, but showed less brain response during risky decision-making in right dorsolateral prefrontal cortex and right cerebellar regions compared with FHN peers. CONCLUSIONS Despite no behavioral differences on the WOF decision-making task, FHP youth exhibited atypical neural response during risk-taking compared with FHN peers. Atypical brain activity, in regions implicated in executive functioning could lead to reduced cognitive control, which may result in risky choices regarding alcohol use. This could help explain the higher rates of AUDs seen in FHP adolescents. Further examination of risky behavior and associated brain response over the course of adolescence is necessary to characterize the vulnerabilities of FHP youth in the absence of alcohol abuse.

Resting state functional connectivity of the nucleus accumbens in youth with a family history of alcoholism.

Adolescents with a family history of alcoholism (FHP) are at heightened risk for developing alcohol use disorders (AUDs). The nucleus accumbens (NAcc), a key brain region for reward processing, is implicated in the development of AUDs. Thus, functional connectivity of the NAcc may be an important marker of risk in FHP youth. Resting state functional magnetic resonance imaging (rs-fcMRI) was used to examine the intrinsic connectivity of the NAcc in 47 FHP and 50 family history negative (FHN) youth, ages 10-16 years old. FHP and FHN adolescents showed significant group differences in resting state synchrony between the left NAcc and bilateral inferior frontal gyri and the left postcentral gyrus (PG). Additionally, FHP youth differed from FHN youth in right NAcc functional connectivity with the left orbitofrontal cortex (OFC), left superior temporal gyrus, right cerebellum, left PG, and right occipital cortex. These results indicate that FHP youth have less segregation between the NAcc and executive functioning brain regions, and less integration with reward-related brain areas, such as the OFC. The findings of the current study highlight that premorbid atypical connectivity of appetitive systems, in the absence of heavy alcohol use, may be a risk marker in FHP adolescents.

Atypical frontal lobe activity during verbal working memory in youth with a family history of alcoholism

BACKGROUND Abnormal brain functioning during verbal working memory (VWM) tasks has been shown in individuals with alcohol use disorders (AUDs). Since adolescents with a familial history of alcoholism (FHP) are at high risk for developing an AUD, it is important to consider whether atypical brain activity during VWM may help to explain FHP vulnerability toward developing alcoholism. METHODS To that end, using functional magnetic resonance imaging, we examined brain response during a VWM 2-back task in 19 FHP adolescents and 16 age and gender-matched family history negative (FHN) controls. RESULTS Despite no group differences in task accuracy, FHP youth had significantly slower average reaction time when making correct responses during the 2-back condition than FHN youth. In contrast to a vigilance control condition, while covarying for reaction time, FHP adolescents showed less activation during VWM than FHN youth in multiple areas of the prefrontal cortex (PFC)--a brain region crucial to intact working memory skills. CONCLUSIONS These results suggest that even prior to heavy alcohol use, FHP adolescents show atypical executive brain functioning during VWM, and that these differences are independent of slower working memory reaction time in FHP youth. Given the importance of working memory in numerous areas of day-to-day functioning, such as adaptive decision-making, these abnormalities may contribute to FHP youth vulnerability toward developing AUDs.

Developmental sex differences in resting state functional connectivity of amygdala sub-regions

During adolescence, considerable social and biological changes occur that interact with functional brain maturation, some of which are sex-specific. The amygdala is one brain area that has displayed sexual dimorphism, specifically in socio-affective (superficial amygdala [SFA]), stress (centromedial amygdala [CMA]), and learning and memory (basolateral amygdala [BLA]) processing. The amygdala has also been implicated in mood and anxiety disorders which display sex-specific features, most prominently observed during adolescence. Using functional magnetic resonance imaging (fMRI), the present study examined the interaction of age and sex on resting state functional connectivity (RSFC) of amygdala sub-regions, BLA and SFA, in a sample of healthy adolescents between the ages 10 and 16 years (n = 122, 71 boys). Whole-brain, voxel-wise partial correlation analyses were conducted to determine RSFC of bilateral BLA and SFA seed regions, created using the Eickhoff-Zilles maximum probability maps based on cytoarchitectonic mapping and FMRIBs Integrated Registration and Segmentation Tool (FIRST). Monte Carlo simulation was implemented to correct for multiple comparisons (threshold of 53 contiguous voxels with a z-value ≥ 2.25). Results indicated that with increasing age, there was a corresponding decrease in RSFC between both amygdala sub-regions and parieto-occipital cortices, with a concurrent increase in RSFC with medial prefrontal cortex (mPFC). Specifically, boys and girls demonstrated increased coupling of mPFC and left and right SFA with age, respectively; however, neither sex showed increased connectivity between mPFC and BLA, which could indicate relative immaturity of fronto-limbic networks that is similar across sex. A dissociation in connectivity between BLA- and SFA-parieto-occipital RSFC emerged, in which girls had weaker negative RSFC between SFA and parieto-occipital regions and boys had weaker negative RSFC of BLA and parieto-occipital regions with increased age, both standing in contrast to adult patterns of amygdala sub-regional RSFC. The present findings suggest relative immaturity of amygdala sub-regional RSFC with parieto-occipital cortices during adolescence, with unique patterns in both sexes that may support memory and socio-affective processing in boys and girls, respectively. Understanding the underlying normative functional architecture of brain networks associated with the amygdala during adolescence may better inform future research of the neural features associated with increased risk for internalizing psychopathology.

High and low sensation seeking adolescents show distinct patterns of brain activity during reward processing

Previous research has shown that personality characteristics, such as sensation seeking (SS), are strong predictors of risk-taking behavior during adolescence. However, the relationship between levels of SS and brain response has not been studied during this time period. Given the prevalence of risky behavior during adolescence, it is important to understand neurobiological differences in reward sensitivity between youth with high and low SS personalities. To this end, we used functional magnetic resonance imaging (fMRI) to examine differences in brain activity in an adolescent sample that included 27 high (HSS) and 27 low sensation seekers (LSS), defined by the Impulsive Sensation Seeking scale of the Zuckerman-Kuhlman Personality Questionnaire (Zuckerman et al., 1993). In the scanner, participants played a modified Wheel of Fortune decision-making task (Cservenka and Nagel, 2012) that resulted in trials with monetary Wins or No Wins. We compared age- and sex-matched adolescent HSS and LSS (mean age=13.94±1.05) on brain activity by contrasting Win vs. No Win trials. Our findings indicate that HSS show greater bilateral insular and prefrontal cortex (PFC) brain response on Win vs. No Win compared to LSS. Analysis of simple effects showed that while LSS showed comparable brain activity in these areas during Wins and No Wins, HSS showed significant differences in brain response to winning (activation) vs. not winning (deactivation), with between-group comparison suggesting significant differences in brain response, largely to reward absence. Group differences in insular activation between reward receipt and absence may suggest weak autonomic arousal to negative outcomes in HSS compared with LSS. Additionally, since the PFC is important for goal-directed behavior and attention, the current results may reflect that HSS allocate fewer attentional resources to negative outcomes than LSS. This insensitivity to reward absence in HSS may lead to a greater likelihood of maladaptive choices when negative consequences are not considered, and may be an early neural marker of decreased loss sensitivity that has been seen in addiction. This neurobiological information may ultimately be helpful in establishing prevention strategies aimed at reducing youth risk-taking and suggests value in further examination of neural associations with personality characteristics during adolescence.

Neurobiological phenotypes associated with a family history of alcoholism

BACKGROUND Individuals with a family history of alcoholism are at much greater risk for developing an alcohol use disorder (AUD) than youth or adults without such history. A large body of research suggests that there are premorbid differences in brain structure and function in family history positive (FHP) individuals relative to their family history negative (FHN) peers. METHODS This review summarizes the existing literature on neurobiological phenotypes present in FHP youth and adults by describing findings across neurophysiological and neuroimaging studies. RESULTS Neuroimaging studies have shown FHP individuals differ from their FHN peers in amygdalar, hippocampal, basal ganglia, and cerebellar volume. Both increased and decreased white matter integrity has been reported in FHP individuals compared with FHN controls. Functional magnetic resonance imaging studies have found altered inhibitory control and working memory-related brain response in FHP youth and adults, suggesting neural markers of executive functioning may be related to increased vulnerability for developing AUDs in this population. Additionally, brain activity differences in regions involved in bottom-up reward and emotional processing, such as the nucleus accumbens and amygdala, have been shown in FHP individuals relative to their FHN peers. CONCLUSIONS It is critical to understand premorbid neural characteristics that could be associated with cognitive, reward-related, or emotional risk factors that increase risk for AUDs in FHP individuals. This information may lead to the development of neurobiologically informed prevention and intervention studies focused on reducing the incidence of AUDs in high-risk youth and adults.

Emotional Processing and Brain Activity in Youth at High Risk for Alcoholism

BACKGROUND Even in the absence of heavy alcohol use, youth with familial alcoholism (family history positive [FHP]) exhibit atypical brain functioning and behavior. Although emotional and cognitive systems are affected in alcohol use disorders (AUDs), little attention has focused on whether brain and behavior phenotypes related to the interplay between affective and executive functioning may be a premorbid risk factor for the development of AUDs in FHP youth. METHODS Twenty-four FHP and 22 family history negative (FHN) 12- to 16-year-old adolescents completed study procedures. After exclusion of participants with clinically significant depressive symptoms and those who did not meet performance criteria during an Emotional Go-NoGo task, 19 FHP and 17 FHN youth were included in functional magnetic resonance imaging (fMRI) analyses. Resting state functional connectivity MRI, using amygdalar seed regions, was analyzed in 16 FHP and 18 FHN youth, after exclusion of participants with excessive head movement. RESULTS fMRI showed that brain activity in FHP youth, compared with FHN peers, was reduced during emotional processing in the superior temporal cortex, as well as during cognitive control within emotional contexts in frontal and striatal regions. Group differences in resting state amygdalar connectivity were seen bilaterally between FHP and FHN youth. In FHP youth, reduced resting state synchrony between the left amygdala and left superior frontal gyrus was related to poorer response inhibition, as measured during the fMRI task. CONCLUSIONS To our knowledge, this is the first study to examine emotion-cognition interactions and resting state functional connectivity in FHP youth. Findings from this research provide insight into neural and behavioral phenotypes associated with emotional processing in familial alcoholism, which may relate to increased risk of developing AUDs.

Atypical Spatial Working Memory and Task‐General Brain Activity in Adolescents with a Family History of Alcoholism

BACKGROUND Altered behavioral performance and brain activation during spatial working memory (SWM) tasks have been demonstrated in individuals with an alcohol use disorder (AUD). It is possible that alterations in processing during SWM may be present prior to initiation of heavy alcohol use in adolescents with a family history of AUDs (family history positive [FHP]) and therefore represent a premorbid neural phenotype that could increase risk for developing an AUD. The goal of our study was to investigate group differences in brain activation during a SWM task between FHP adolescents and adolescents with no family history of AUDs (family history negative [FHN]), as well as examine the relationship between brain activation and individual differences in family history density (FHD) of AUDs. METHODS Eighteen FHP and 16 gender and age-matched FHN participants completed a SWM and vigilance task while undergoing a functional magnetic resonance imaging (fMRI) scan. RESULTS There were no group differences in task performance. The FHN group demonstrated expected greater activation during the SWM than vigilance condition in the right middle frontal gyrus and dorsolateral prefrontal cortex, whereas the FHP group demonstrated comparable brain activation for both the more demanding and simple task conditions. Additionally, FHD was associated with greater activation of the right superior parietal cortex and less activation of the right cerebellum during the SWM task, but not during the vigilance task. CONCLUSIONS Results suggest FHP adolescents demonstrate alterations in activation of prefrontal regions that are related more generally to the maintenance of top-down cognitive control and alterations in parietal and cerebellar regions that are specific to SWM. Alterations in top-down cognitive control may be a general risk factor for FHP adolescents, whereas SWM-specific alterations are seen as a function of family history loading.

The Burden of Binge and Heavy Drinking on the Brain: Effects on Adolescent and Young Adult Neural Structure and Function

Introduction: Adolescence and young adulthood are periods of continued biological and psychosocial maturation. Thus, there may be deleterious effects of consuming large quantities of alcohol on neural development and associated cognition during this time. The purpose of this mini review is to highlight neuroimaging research that has specifically examined the effects of binge and heavy drinking on adolescent and young adult brain structure and function. Methods: We review cross-sectional and longitudinal studies of young binge and heavy drinkers that have examined brain structure (e.g., gray and white matter volume, cortical thickness, white matter microstructure) and investigated brain response using functional magnetic resonance imaging (fMRI). Results: Binge and heavy-drinking adolescents and young adults have systematically thinner and lower volume in prefrontal cortex and cerebellar regions, and attenuated white matter development. They also show elevated brain activity in fronto-parietal regions during working memory, verbal learning, and inhibitory control tasks. In response to alcohol cues, relative to controls or light-drinking individuals, binge and heavy drinkers show increased neural response mainly in mesocorticolimbic regions, including the striatum, anterior cingulate cortex (ACC), hippocampus, and amygdala. Mixed findings are present in risky decision-making tasks, which could be due to large variation in task design and analysis. Conclusions: These findings suggest altered neural structure and activity in binge and heavy-drinking youth may be related to the neurotoxic effects of consuming alcohol in large quantities during a highly plastic neurodevelopmental period, which could result in neural reorganization, and increased risk for developing an alcohol use disorder (AUD).

Reduced cerebellar brain activity during reward processing in adolescent binge drinkers

Highlights • Adolescent binge drinkers have reduced cerebellar activity during reward outcome.• Average drinks consumed/drinking day was negatively related to brain activity.• Salience of rewards may be blunted because of alcohol-induced neurotoxicity.