The effects of alcohol on sequential decision-making biases during gambling.

RATIONALE: Gambling and alcohol use are recreational behaviours that share substantial commonalities at a phenomenological, clinical and neurobiological level. Past studies have shown that alcohol can have a disinhibiting effect on gambling behaviour, in terms of bet size and persistence. OBJECTIVES: This study was conducted in order to characterise how alcohol affects biases in judgment and decision-making that occur during gambling, with a focus on sequential decision-making including the gambler's fallacy. METHODS: Sequential biases were elicited via a roulette-based gambling task. Using a standard between-groups alcohol challenge procedure, male participants played the roulette task 20 min after receiving an alcoholic (0.8 g/kg; n = 22) or placebo (n = 16) beverage. The task measured colour choice decisions (red/black) and bet size, in response to varying lengths of colour runs and winning/losing feedback streaks. RESULTS: Across both groups, a number of established sequential biases were observed. On colour choice, there was an effect of run length in line with the gambler's fallacy, which further varied by previous feedback (wins vs losses). Bet size increased with feedback streaks, especially for losing streaks. Compared to placebo, the alcohol group placed higher bets following losses compared to wins. CONCLUSIONS: Increased bet size after losses following alcohol consumption may reflect increased loss chasing that may amplify gambling harms. Our results do not fit a simple pattern of enhanced gambling distortions or reward sensitivity, but help contextualise the effects of alcohol on gambling to research on decision-making biases.

Role Reversal: The Influence of Slot Machine Gambling on Subsequent Alcohol Consumption.

Experimental studies examining the relationship between alcohol use and gambling have focused predominantly on alcohol's influence on gambling behavior. There has been little consideration of the reverse pathway: whether gambling influences subsequent alcohol use. Two experiments examined whether gambling and gambling outcomes (i.e. profits during a gambling session) influenced subsequent alcohol consumption. Experiment 1 (n = 53) used an ad libitum consumption test, in which participants could request beverages during a 30 min window. Experiment 2 (n = 29) used a beer taste test procedure, in which participants were asked to rate a series of beers. In both studies, male regular gamblers were assigned to watch a television show or play a modern slot machine for 30 min, before being provided with access to alcohol. On the ad libitum procedure, gambling significantly increased the number of alcoholic drinks ordered, the volume of alcohol consumed, the participants' speed of drinking, and their intention to drink alcohol. These effects were not corroborated using the taste test procedure. Across both studies, gambling outcomes were not associated with alcohol consumption. In conjunction with prior findings, the observation that gambling can promote alcohol consumption under certain conditions highlights a possible feedback loop whereby gambling and alcohol reinforce one another. However, the divergent results between the ad libitum and taste test experiments point to boundary conditions for the effect and raise methodological considerations for future work measuring alcohol consumption in gambling environments.

Let me take the wheel: Illusory control and sense of agency.

Illusory control refers to an effect in games of chance where features associated with skilful situations increase expectancies of success. Past work has operationalized illusory control in terms of subjective ratings or behaviour, with limited consideration of the relationship between these definitions, or the broader construct of agency. This study used a novel card-guessing task in 78 participants to investigate the relationship between subjective and behavioural illusory control. We compared trials in which participants (a) had no opportunity to exercise illusory control, (b) could exercise illusory control for free, or (c) could pay to exercise illusory control. Contingency Judgment and Intentional Binding tasks assessed explicit and implicit sense of agency, respectively. On the card-guessing task, confidence was higher when participants exerted control than in the baseline condition. In a complementary model, participants were more likely to exercise control when their confidence was high, and this effect was accentuated in the pay condition relative to the free condition. Decisions to pay were positively correlated with control ratings on the Contingency Judgment task, but were not significantly related to Intentional Binding. These results establish an association between subjective and behavioural illusory control and locate the construct within the cognitive literature on agency.

Microstructural white matter changes in the corpus callosum of young people with Bipolar Disorder: a diffusion tensor imaging study.

To date, most studies of white matter changes in Bipolar Disorder (BD) have been conducted in older subjects and with well-established disorders. Studies of young people who are closer to their illness onset may help to identify core neurobiological characteristics and separate these from consequences of repeated illness episodes or prolonged treatment. Diffusion tensor imaging (DTI) was used to examine white matter microstructural changes in 58 young patients with BD (mean age 23 years; range 16-30 years) and 40 controls. Whole brain voxelwise measures of fractional anisotropy (FA), parallel diffusivity (λ//) and radial diffusivity (λ⊥) were calculated for all subjects. White matter microstructure differences (decreased FA corrected p<.05) were found between the patients with BD and controls in the genu, body and splenium of the corpus callosum as well as the superior and anterior corona radiata. In addition, significantly increased radial diffusivity (p<.01) was found in the BD group. Neuroimaging studies of young patients with BD may help to clarify neurodevelopmental aspects of the illness and for identifying biomarkers of disease onset and progression. Our findings provide evidence of microstructural white matter changes early in the course of illness within the corpus callosum and the nature of these changes suggest they are associated with abnormalities in the myelination of axons.

Pathways to alcohol-induced brain impairment in young people: a review.

Classically, disorders associated with 'alcohol-related brain damage' (ARBD) occur as a result of chronic excessive alcohol misuse and confer significant physical and psychological disability to the individual as well as to the community. These phenotypes are often difficult to detect at early stages and therefore early intervention and treatment is limited. It remains unresolved as to whether there are neurobiological markers of the early stages of such brain damage in young 'at-risk' drinkers, who probably experience 'alcohol-induced brain impairment' prior to the onset of ARBD, per se. This review focuses on neurobiological (in particular, neuropsychological and neuroimaging) markers that are associated with alcohol misuse in young people (13-24 years of age). The findings from this review suggest that a clearer understanding of alcohol misuse (particularly with regards to binge drinking) is needed. Despite this, neurocognitive profile along with supporting neuroimaging evidence appears to be particularly important in the early detection of brain changes that result from excessive alcohol use. In young alcohol misusers, these preventable and potentially reversible deficits may be progressive but if left unresolved such deficits eventually become major contributors to poor outcome (long term) and hamper adherence to treatment. We address five key themes in this review: (i) there are specific drinking patterns in young people; (ii) youth represents a critical period in brain development that is particularly vulnerable to alcohol misuse; (iii) the extent to which there are pre-existing versus alcohol-induced neurobiological changes remains unclear; (iv) vulnerability markers may be mediated by mental health and substance use comorbidities; and (v) cognitive remediation would be a likely candidate for early prevention and treatment as it could help to develop efficient meta-cognitive skills to prevent relapse in young drinkers.

Effects of acute alcohol consumption on executive cognitive functioning in naturalistic settings.

Laboratory studies have demonstrated that acute alcohol intoxication can disrupt performance on neuropsychological tests of executive cognitive functioning such as the Wisconsin Card Sorting Test (WCST). However, the generalizability of such findings to typical self-regulated alcohol intake in social settings can be questioned. In the present study, 86 young adults were recruited at Australian bars to perform a computer version of the WCST. Participants displayed blood alcohol concentrations (BACs) across a range from 0 to 0.15%. Although self-report measures of typical alcohol consumption, impulsivity, and frontal lobe related everyday functioning were all intercorrelated in line with other recent findings, multiple regression indicated that these measures did not predict perseverative errors (PE) nor non-perseverative errors (NPE) on the WCST, whereas BAC uniquely predicted PE but not NPE. The results were consistent with a dose-dependent selective disruption of prefrontal cortical functioning by alcohol. There were no differences in performance between participants tested on the ascending limb of the BAC curve and those tested on the descending limb. Alcohol-associated perseveration may reflect the inhibitory effect of alcohol-induced dopamine release in the prefrontal cortex.