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Background: Alcohol intoxication disrupts many aspects of cognition, including the generation of phenomenological characteristics of future events (a component of episodic foresight), and the execution of directed preparatory behaviours (a component of prospective memory). However, no study has tested whether alcohol intoxication is also associated with deficits engaging episodic foresight to guide future-directed behaviour. Aims: This study was designed to provide the first test of how alcohol intoxication influences the functional application of episodic foresight. The secondary aim was to establish the degree to which any observed episodic foresight difficulties associated with alcohol use might reflect broader problems in retrospective memory and executive control. Sex differences were also examined. Methods: Healthy adult social drinkers randomly received either a moderate dose of 0.6 g/kg alcohol ( n = 61) or a matched placebo drink ( n = 63) and then completed a validated measure that met strict criteria for assessing the functional application of episodic foresight as well as a broader cognitive test battery. Results: Relative to the placebo condition, episodic foresight was impaired by acute alcohol consumption, with this impairment related to poorer retrospective memory, but not executive control. The negative effects of alcohol intoxication on episodic foresight did not differ as a function of sex. Conclusions: Even a moderate level of intoxication impairs the ability to use episodic foresight in a functionally adaptive way. These findings have implications for understanding many of the maladaptive behaviours that are often associated with acute alcohol use.

Rationale Acute alcohol consumption adversely affects many cognitive abilities, including episodic memory and executive functioning. However, no study to date has tested whether these acute effects of alcohol also extend to episodic future thinking (EFT). This is a surprising omission given that EFT refers to the ability to imagine oneself experiencing the future, a highly adaptive ability that has been implicated in many important functional behaviours. EFT is also thought to impose demands on episodic memory and executive control. Objectives The current study was designed to provide the first test of whether a moderate dose of alcohol influences EFT and whether any observed EFT difficulties are secondary to broader problems in episodic memory and executive functioning. Sex differences in EFT following acute alcohol consumption were also examined. Methods One hundred and twenty-four healthy adult social drinkers were recruited and randomly assigned to either the alcohol (n = 61) or placebo (n = 63) condition. Participants were administered a dose of 0.6 g/kg alcohol or a matched placebo drink. Results Relative to the placebo condition, EFT was impaired by acute alcohol consumption. This impairment was underpinned by broader difficulties with episodic memory, but not executive functioning. There were no sex differences in EFT performance following acute alcohol use. Conclusion These data provide novel insights into the effects of acute alcohol consumption on EFT and the broader cognitive mechanisms that contribute to these difficulties. The results are discussed in relation to their implications for understanding many of the maladaptive behaviours commonly associated with acute alcohol use.

BackgroundSocial anxiety disorder (SAD) is a prevalent and disabling mental health condition, characterized by excessive fear and anxiety in social situations. Resting-state functional magnetic resonance imaging (fMRI) paradigms have been increasingly used to understand the neurobiological underpinnings of SAD in the absence of threat-related stimuli. Previous studies have primarily focused on the role of the amygdala in SAD. However, the amygdala consists of functionally and structurally distinct subregions, and recent studies have highlighted the importance of investigating the role of these subregions independently.MethodUsing multiband fMRI, we analyzed resting-state data from 135 participants (42 SAD, 93 healthy controls). By employing voxel-wise permutation testing, we examined group differences of fMRI connectivity and associations between fMRI connectivity and social anxiety symptoms to further investigate the classification of SAD as a categorical or dimensional construct.ResultsSeed-to-whole brain functional connectivity analysis using multiple ‘seeds’ including the amygdala and its subregions and the precuneus, revealed no statistically significant group differences. However, social anxiety severity was significantly negatively correlated with functional connectivity of the precuneus - perigenual anterior cingulate cortex and positively correlated with functional connectivity of the amygdala (specifically the superficial subregion) - parietal/cerebellar areas.ConclusionOur findings demonstrate clear links between symptomatology and brain connectivity in the absence of diagnostic differences, with evidence of amygdala subregion-specific alterations. The observed brain-symptom associations did not include disturbances in the brain’s fear circuitry (i.e., disturbances in connectivity between amygdala - prefrontal regions) likely due to the absence of threat-related stimuli.

Rationale Regular cannabis use (i.e. ≥ monthly) is highly prevalent, with past year use being reported by ~ 200 million people globally.High reactivity to cannabis cues is a key feature of regular cannabis use and has been ascribed to greater cannabis exposure and craving, but the underlying neurobiology is yet to be systematically integrated. Objectives We aim to systematically summarise the findings from fMRI studies which examined brain function in cannabis users while exposed to cannabis vs neutral stimuli during a cue-reactivity fMRI task. Methods A systematic search of PsycINFO, PubMed and Scopus databases was pre-registered in PROSPERO (CRD42020171750) and conducted following PRISMA guidelines. Eighteen studies met inclusion/exclusion criteria. Samples comprised 918 participants (340 female) aged 16–38 years. Of these, 603 were regular cannabis users, and 315 were controls. Results The literature consistently reported greater brain activity in cannabis users while exposed to cannabis vs neutral stimuli in three key brain areas: the striatum, the prefrontal (anterior cingulate, middle frontal) and the parietal cortex (posterior cingulate/precuneus) and additional brain regions (hippocampus, amygdala, thalamus, occipital cortex). Preliminary correlations emerged between cannabis craving and the function of partially overlapping regions (amygdala, striatum, orbitofrontal cortex ). Conclusions Exposure to cannabis-cues may elicit greater brain function and thus trigger cravings in regular cannabis users and thus trigger cannabis craving. Standardised and longitudinal assessments of cannabis use and related problems are required to profile with greater precision the neurobiology of cannabis cue-reactivity, and its role in predicting cravings and relapse.

Background: Long-term opiate users experience pervasive social difficulties, but there has been surprisingly limited research focused on social-cognitive functioning in this population. Aim: The aim of this study was to investigate whether three important aspects of social cognition (facial emotion recognition, theory of mind (ToM) and rapid facial mimicry) differ between long-term opiate users and healthy controls. Methods: The participants were 25 long-term opiate users who were enrolled in opiate substitution programmes, and 25 healthy controls. Facial emotion recognition accuracy was indexed by responses to 60 photographs of faces depicting the six basic emotions (happiness, sadness, anger, fear, surprise and disgust). ToM was assessed using the Reading the Mind in the Eyes task, which requires participants to infer mental states of others from partial facial cues. Rapid facial mimicry was assessed by recording activity in the zygomaticus major and corrugator supercilii muscle regions while participants passively viewed images of happy and angry facial expressions. Results: Relative to the control group, the opiate user group exhibited deficits in both facial emotion recognition and ToM. Moreover, only control participants exhibited typical rapid facial mimicry responses to happy facial expressions. Conclusions: These data indicate that long-term opiate users exhibit abnormalities in three distinct areas of social-cognitive processing, pointing to the need for additional work to establish how social-cognitive functioning relates to functional outcomes in this group. Such work may ultimately inform the development of interventions aimed at improving treatment outcomes for long-term opiate users.

Opiate use is associated with deficits in decision-making. However, the impact of abstinence and co-morbid factors, like head injury and poly-substance abuse, on this ability, is currently unclear. This meta-analysis aimed to assess 1) the magnitude of decision-making deficits in opiate users; 2) whether co-morbid factors moderate the severity of these deficits; 3) whether ex-opiate users demonstrate smaller decision-making deficits than current users; and 4) whether the length of abstinence is related to the magnitude of decision-making deficits. We analysed 22 studies that compared the performance of current and ex-opiate users to healthy controls on decision-making measures such as the Iowa Gambling Task. Current users demonstrated a moderately strong impairment in decision-making relative to controls, which was not significantly moderated by co-morbid factors. The magnitude of the impairment did not significantly differ between studies assessing current or ex-users, and this impairment was not related to length of abstinence. Thus, it appears that opiate users have relatively severe decision-making deficits that persist at least 1.5 years after cessation of use.