Mapping the Neural Substrates of Cocaine Craving: A Systematic Review.

Craving is one of the most important symptoms of cocaine use disorder (CUD) since it contributes to the relapse and persistence of such disorder. This systematic review aimed to investigate which brain regions are modulated during cocaine craving. The articles were obtained through searches in the Google Scholar, Regional BVS Portal, PubMed, and Scielo databases. Overall, there was a selection of 36 studies with 1574 individuals, the majority being participants with CUD, whereby about 61.56% were individuals with CUD and 38.44% were controls (mean age = 40.4 years). Besides the methodological points, the neurobiological investigations comprised fMRI (58.34%) and PET (38.89%). The induction of cocaine craving was studied using different methods: exposure to cocaine cues (69.45%), stressful stimuli, food cues, and methylphenidate. Brain activations demonstrated widespread activity across the frontal, parietal, temporal, and occipital lobes, basal ganglia, diencephalon, brainstem, and the limbic system. In addition to abnormalities in prefrontal cortex activity, abnormalities in various other brain regions' activity contribute to the elucidation of the neurobiology of cocaine craving. Abnormalities in brain activity are justified not only by the dysfunction of dopaminergic pathways but also of the glutamatergic and noradrenergic pathways, and distinct ways of inducing craving demonstrated the involvement of distinct brain circuits and regions.

Risky business: an examination of drinking games in college settings and their impact: a systematic review.

This systematic review explores the prevalence and impact of Drinking Games (DG) among college students. DGs involve social drinking with the goal of heavy alcohol consumption and are associated with risky behaviours. The review aims to quantify the relationship between DG participation, alcohol consumption, and negative outcomes. It also investigates gender moderation and unexplored motivational factors for DG engagement. Following PRISMA guidelines, 34 studies were included after screening 317 records. The studies comprised n = 34,197 participants and were analysed for various variables, including gender dynamics, motivations, and associated negative consequences. Gender convergence in DG participation was noted, emphasizing the importance of gender-specific interventions. Participants were aware of risks but often perceived negative outcomes as a badge of honour. Motivations for DGs were linked to social interaction and a sense of belonging. Personality traits like sensation seeking and identification with college drinking culture played significant roles in DG engagement and outcomes. The review underscores the need for targeted interventions to address shifting perceptions of negative consequences and consider personality traits when designing preventive measures. It also highlights the significance of gender-specific strategies. However, variations in DG measurement and possible selection bias among heavy drinkers participating in DGs remain limitations. This systematic review provides insights into DG prevalence and its link to negative outcomes among college students. The findings stress the importance of tailored interventions and further research to mitigate risk factors and promote healthier drinking behaviours in this demographic.

Brain Correlates of the Alcohol Use Disorder Pharmacotherapy Response: A Systematic Review of Neuroimaging Studies.

BACKGROUND: Although Alcohol Use Disorder (AUD) is highly prevalent worldwide, treating this condition remains challenging. Further, potential treatments for AUD do not fully address alcohol-induced neuroadaptive changes. Understanding the effects of pharmacotherapies for AUD on the human brain may lead to tailored, more effective treatments, and improved individual clinical outcomes. OBJECTIVES: We systematically reviewed the literature for studies investigating pharmacotherapies for AUD that included neuroimaging-based treatment outcomes. We searched the PubMed, Scielo, and PsycINFO databases up to January 2021. STUDY ELIGIBILITY CRITERIA, PARTICIPANTS, AND INTERVENTIONS: Eligible studies included those investigating pharmacotherapies for AUD and employing functional magnetic resonance imaging (fMRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), and/or proton magnetic resonance spectroscopy (H-MRS). STUDY APPRAISAL AND SYNTHESIS METHODS: Two independent reviewers screened studies' titles and abstracts for inclusion. Data extraction forms were shared among all the authors to standardize data collection. We gathered information on the following variables: sample size; mean age; sociodemographic and clinical characteristics; alcohol use status; study design and methodology; main neuroimaging findings and brain-regions of interest (i.e., brain areas activated by alcohol use and possible pharmacological interactions); and limitations of each study. RESULTS: Out of 177 studies selected, 20 studies provided relevant data for the research topic. Findings indicate that: (1) Acamprosate and gabapentin may selectively modulate limbic regions and the anterior cingulate cortex; (2) Naltrexone and disulfiram effects may involve prefrontal, premotor, and cerebellar regions; (3) Pharmacotherapies acting on glutamate and GABA neurotransmission involve primarily areas underpinning reward and negative affective states, and; (4) Pharmacotherapies acting on opioid and dopamine systems may affect areas responsible for the cognitive and motor factors of AUD. LIMITATIONS: Most of the studies were focused on naltrexone. A small number of studies investigated the action of disulfiram and gabapentin, and no neuroimaging studies investigated topiramate. In addition, the time between medication and neuroimaging scans varied widely across studies. CONCLUSIONS: We identified key-brain regions modulated by treatments available for AUD. Some of the regions modulated by naltrexone are not specific to the brain reward system, such as the parahippocampal gyrus (temporal lobe), parietal and occipital lobes. Other treatments also modulate not specific regions of the reward system, but play a role in the addictive behaviors, including the insula and dorsolateral prefrontal cortex. The role of these brain regions in mediating the AUD pharmacotherapy response warrants investigation in future research studies.