Specialization of amygdala subregions in emotion processing.

The amygdala is important for human fear processing. However, recent research has failed to reveal specificity, with evidence that the amygdala also responds to other emotions. A more nuanced understanding of the amygdala's role in emotion processing, particularly relating to fear, is needed given the importance of effective emotional functioning for everyday function and mental health. We studied 86 healthy participants (44 females), aged 18-49 (mean 26.12 ± 6.6) years, who underwent multiband functional magnetic resonance imaging. We specifically examined the reactivity of four amygdala subregions (using regions of interest analysis) and related brain connectivity networks (using generalized psycho-physiological interaction) to fear, angry, and happy facial stimuli using an emotional face-matching task. All amygdala subregions responded to all stimuli (p-FDR < .05), with this reactivity strongly driven by the superficial and centromedial amygdala (p-FDR < .001). Yet amygdala subregions selectively showed strong functional connectivity with other occipitotemporal and inferior frontal brain regions with particular sensitivity to fear recognition and strongly driven by the basolateral amygdala (p-FDR < .05). These findings suggest that amygdala specialization to fear may not be reflected in its local activity but in its connectivity with other brain regions within a specific face-processing network.

Self-initiating and applying episodic foresight in middle childhood.

This study provides an important extension to the growing literature on prospection in children by providing the first test of whether one's ability to engage in the functional (as opposed to the purely phenomenological) aspect of episodic foresight improves across middle childhood. Of the various forms of prospection, episodic foresight has been proposed to be one of the most flexible and functionally powerful, defined as the ability to not only imagine future events (simulative aspect) but also use those imaginings to guide behavior in the present (functional aspect). The current study tested 80 typically developing children aged 8 to 12 years using an extensive cognitive battery comprising Virtual Week Foresight, the Autobiographical Interview, and a series of crystallized and fluid intelligence measures. Whereas data indicated age-related improvements in detecting future-oriented problems and taking steps in the present in service of solving these, all children in this age bracket demonstrated a similar capacity for problem resolution (i.e., the ability to subsequently solve successfully identified problems). Results also revealed the importance of broader crystallized and fluid intelligence, but not episodic memory or episodic future thinking, in engaging in this capacity. Research is now required to understand the real-life consequences of episodic foresight during this developmental period as well as the ways in which parents and teachers can help to foster this capacity and consequently help to support children's growing desire for independence during this time.

Age Differences in Emotion Regulation and Facial Muscle Reactivity to Emotional Films.

BACKGROUND: Age-related declines in many cognitive abilities are common in healthy aging. However, the ability to effectively regulate emotions is preserved, and possibly even enhanced, in late adulthood. This capacity has been examined most commonly in relation to low-intensity emotional stimuli that typically involve static pictures. Evidence is suggesting that older adults may become overwhelmed when exposed to emotional cues of heightened intensity. OBJECTIVE: In the current study, we assessed whether older adults retain the ability to regulate emotions successfully when exposed to more emotionally evocative (e.g., dynamic) stimuli. METHODS: Young and older adults were instructed to regulate, using expressive suppression, their outward behavioral expression of emotions while viewing dynamic stimuli involving amusing and sad films. Facial reactivity, as indexed using electromyography, self-rated emotional experience, and memory for the stimuli were assessed. RESULTS: The results showed that, relative to young adults, older adults were unable to suppress zygomaticus (cheek) activity to amusing films or corrugator (brow) reactivity to sad films, which is likely due to their relatively reduced facial muscle reactivity. Expressive suppression did not affect young or older adults' subjective feelings or memory for the stimuli. CONCLUSION: Our findings suggest that there are age differences in facial muscle reactivity to amusing and sad cues of heightened intensity. These findings suggest that older adults' ability to effectively regulate emotions may be limited, at least with expressive suppression, in the context of high-intensity emotional cues. Further research is needed to investigate possible exceptions the preservation of emotion regulation in older adults.

The relationship between episodic future thinking and prospective memory in middle childhood: Mechanisms depend on task type.

Episodic future thinking (EFT), the ability to imagine experiencing a future event, and prospective memory (PM), the ability to remember and carry out a planned action, are core aspects of future-oriented cognition that have individually been the focus of research attention in the developmental literature. However, the relationship between EFT and PM, including the extent to which it varies with PM task type, remains poorly delineated, particularly in middle childhood. The current study tested this relationship in 62 typically developing children aged 8-12 years. Results indicated that EFT ability was significantly related to performance on three types of PM tasks (regular and irregular event based and regular time based). Age was not found to moderate the relationship. Children's performance on the retrospective memory component of the PM tasks mediated the relationship between EFT ability and their performance on three types of PM tasks. For irregular event-based tasks, however, EFT made an additional significant contribution. This study adds to the limited empirical literature supporting a relationship between EFT and PM in this age band and supports theoretical models arguing that EFT ability may support PM performance by strengthening the encoding of PM task details in retrospective memory. However, additional mechanisms were also indicated for irregular event-based PM tasks, possibly involving strengthening of cue-context associations. These data show for the first time that the contribution of EFT to children's PM performance varies across task types. This study provides an important and novel contribution to current understanding of the processes that underlie PM development.

The relationship between body dysmorphic disorder and obsessive-compulsive disorder: A systematic review of direct comparative studies.

OBJECTIVE: Current nosology conceptualises body dysmorphic disorder as being related to obsessive-compulsive disorder, but the direct evidence to support this conceptualisation is mixed. In this systematic review, we aimed to provide an integrated overview of research that has directly compared body dysmorphic disorder and obsessive-compulsive disorder. METHOD: The PubMed database was searched for empirical studies which had directly compared body dysmorphic disorder and obsessive-compulsive disorder groups across any subject matter. Of 379 records, 31 met inclusion criteria and were reviewed. RESULTS: Evidence of similarities between body dysmorphic disorder and obsessive-compulsive disorder was identified for broad illness features, including age of onset, illness course, symptom severity and level of functional impairment, as well as high perfectionism and high fear of negative evaluation. However, insight was clearly worse in body dysmorphic disorder than obsessive-compulsive disorder, and preliminary data also suggested unique visual processing features, impaired facial affect recognition, increased social anxiety severity and overall greater social-affective dysregulation in body dysmorphic disorder relative to obsessive-compulsive disorder. CONCLUSION: Limitations included a restricted number of studies overall, an absence of studies comparing biological parameters (e.g. neuroimaging), and the frequent inclusion of participants with comorbid body dysmorphic disorder and obsessive-compulsive disorder. Risks of interpreting common features as indications of shared underlying mechanisms are explored, and evidence of differences between the disorders are placed in the context of broader research findings. Overall, this review suggests that the current nosological status of body dysmorphic disorder is somewhat tenuous and requires further investigation, with particular focus on dimensional, biological and aetiological elements.

Improving prospective memory performance with future event simulation in traumatic brain injury patients.

OBJECTIVE: Previous studies have shown that traumatic brain injury (TBI) patients have difficulties with prospective memory (PM). Considering that PM is closely linked to independent living it is of primary interest to develop strategies that can improve PM performance in TBI patients. METHOD: This study employed Virtual Week task as a measure of PM, and we included future event simulation to boost PM performance. Study 1 evaluated the efficacy of the strategy and investigated possible practice effects. Twenty-four healthy participants performed Virtual Week in a no strategy condition, and 24 healthy participants performed it in a mixed condition (no strategy - future event simulation). In Study 2, 18 TBI patients completed the mixed condition of Virtual Week and were compared with the 24 healthy controls who undertook the mixed condition of Virtual Week in Study 1. All participants also completed a neuropsychological evaluation to characterize the groups on level of cognitive functioning. RESULTS: Study 1 showed that participants in the future event simulation condition outperformed participants in the no strategy condition, and these results were not attributable to practice effects. Results of Study 2 showed that TBI patients performed PM tasks less accurately than controls, but that future event simulation can substantially reduce TBI-related deficits in PM performance. The future event simulation strategy also improved the controls' PM performance. CONCLUSIONS: These studies showed the value of future event simulation strategy in improving PM performance in healthy participants as well as in TBI patients. PRACTITIONER POINTS: TBI patients performed PM tasks less accurately than controls, confirming prospective memory impairment in these patients. Participants in the future event simulation condition out-performed participants in the no strategy condition. Future event simulation can substantially reduce TBI-related deficits in PM performance. Future event simulation strategy also improved the controls' PM performance.

Stereotype threat and social function in opioid substitution therapy patients.

OBJECTIVES: People with a history of substance abuse are subject to widespread stigmatization. It seems likely that this societal disapproval will result in feelings of stereotype threat, or the belief that one is the target of demeaning stereotypes. If so, stereotype threat has the potential to contribute to functional difficulties including poor social outcomes. METHODS: Eighty drug users on opioid substitution therapy and 84 demographically matched controls completed measures of mental health and social function. The opioid substitution therapy group were additionally asked to complete a measure that focused on their feelings of stereotype threat in relation to their drug use history. Bivariate correlations and hierarchical regression analyses were conducted to establish the magnitude and specificity of the relationship between stereotype threat and social functioning. RESULTS: Relative to controls, the opioid substitution therapy group reported higher levels of negative affect and schizotypy, and poorer social functioning, with all three of these indices significantly correlated with their feelings of stereotype threat. The results also showed that stereotype threat contributed significant unique variance to social functioning in the opioid substitution therapy group, even after taking into account other background, clinical, and mental health variables. CONCLUSIONS: Social functioning is an important aspect of recovery, yet these data indicate that people with a history of drug abuse who believe they are the target of stereotypical attitudes have poorer social functioning. This relationship holds after controlling for the impact of other variables on social functioning, including mental health. The theoretical and practical implications of these findings are discussed. PRACTITIONER POINTS: Concerns about being stereotyped can shape the social experiences of opioid substitution therapy patients. Opioid substitution therapy patients who feel negatively stereotyped experience greater social function deficits, and this relationship emerges after controlling for important clinical and mental health variables. Understanding the relationship between feeling stereotyped and social function may assist practitioners in their treatment. The study is cross-sectional, and thus, experimental or longitudinal research is required to determine the causal direction between stereotype threat and social function.

Deconstructing the nature of episodic foresight deficits associated with chronic opiate use.

OBJECTIVES: Episodic foresight refers to the capacity to mentally travel forward in time and has been linked to a wide variety of important functional behaviours. Evidence has recently emerged that chronic opiate use is associated with deficits in this critical capacity and that these difficulties are not simply a secondary consequence of broader cognitive dysfunction. The current study aimed to better understand the circumstances in which chronic opiate users might be expected to have problems with episodic foresight, by addressing whether deficits reflect compromised scene construction, self-projection, or narrative ability. METHODS: Thirty-five chronic opiate users and 35 demographically matched controls completed an imagination task in which they were instructed to imagine and provide descriptions of an atemporal event, a plausible, self-relevant future event, as well as complete a narrative task. These three imagination conditions systematically varied in their demands on scene construction, self-projection, and narrative ability. RESULTS: Consistent with prior literature, chronic opiate users exhibited reduced capacity for episodic foresight relative to controls. However, this study was the first to show that these difficulties were independent of capacity for scene construction and narration. Instead, a specific impairment in self-projection into the future appears to contribute to the problems with episodic foresight seen in this clinical group. CONCLUSIONS: Deficits in self-projection into the future may have important implications in therapeutic environments given that many relapse prevention strategies rely heavily on the ability to project oneself into an unfamiliar future, free of problem substance use. PRACTITIONER POINTS: A reduced capacity for episodic foresight highlights the importance of refining current relapse prevention protocols that place significant demands for mental time travel into the future. Psychosocial treatments should focus on the attainment of more immediate or short-term goals. It is difficult to delineate the effects of specific substances given long-standing drug use history common to chronic opiate users. Conclusions relating to neurological functioning are speculative given the absence of neuroimaging data.

Prospective memory performance in traumatic brain injury patients: a study of implementation intentions.

Traumatic brain injury (TBI) patients often present with prospective memory (PM) dysfunction. Forgetting to complete tasks may result in a loss of independence, limited employment prospects and anxiety, therefore, it is important to develop programs to improve PM performance in TBI patients. A strategy which may improve PM performance is implementation intentions. It involves making explicit plans specifying when, where and how one will perform a task in the future. In the present study, a group of 36 TBI patients and a group of 34 controls performed Virtual Week using either implementation intentions or no strategy. The results showed that the PM performance of TBI patients was less accurate than controls, in particular when the PM cue was time-based. No effect of implementation intentions was observed for TBI patients, however, controls improved their PM performance when the task was time-based. The findings suggest that strategies to improve PM in this clinical group are likely to be more complex than those that benefit healthy adults and may involve targeting phases of the PM process other than, or in addition to, the intention formation phase.

A Virtual Week study of prospective memory function in autism spectrum disorders.

Prospective memory (PM) refers to the implementation of delayed intentions, a cognitive ability that plays a critical role in daily life because of its involvement in goal-directed behavior and consequently the development and maintenance of independence. Emerging evidence indicates that PM may be disrupted in autism spectrum disorders (ASDs), potentially contributing to the functional difficulties that characterize this group. However, the degree, nature, and specificity of ASD-related impairment remains poorly understood. In the current study, children between 8 and 12 years of age who were diagnosed with ASDs (n=30) were compared with typically developing children (n=30) on a child-appropriate version of the Virtual Week board game. This measure provides an opportunity to investigate the different sorts of PM failures that occur. The ASD group showed significant PM impairment on measures of time-based (but not event-based) prospective remembering. However, only a subtle difference emerged between regular and irregular PM tasks, and group differences were consistent across these tasks. Because regular and irregular tasks differentially load retrospective memory, these data imply that the PM difficulties seen in ASDs may primarily reflect a monitoring deficit and not an encoding and memory storage deficit. PM performance was poorer under conditions of high ongoing task absorption, but the magnitude of this effect did not vary as a function of group. In both groups, time-based (but not event-based) PM difficulties were associated with functional outcomes in daily life, but only an inconsistent association with executive control emerged.

Resting-state amygdala subregion and precuneus connectivity provide evidence for a dimensional approach to studying social anxiety disorder.

Social 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. Using 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. Seed-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. Our 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.

Cannabis Dependence is Associated with Reduced Hippocampal Subregion Volumes Independently of Sex: Findings from an ENIGMA Addiction Working Group Multi-Country Study.

Background: Males and females who consume cannabis can experience different mental health and cognitive problems. Neuroscientific theories of addiction postulate that dependence is underscored by neuroadaptations, but do not account for the contribution of distinct sexes. Further, there is little evidence for sex differences in the neurobiology of cannabis dependence as most neuroimaging studies have been conducted in largely male samples in which cannabis dependence, as opposed to use, is often not ascertained. Methods: We examined subregional hippocampus and amygdala volumetry in a sample of 206 people recruited from the ENIGMA Addiction Working Group. They included 59 people with cannabis dependence (17 females), 49 cannabis users without cannabis dependence (20 females), and 98 controls (33 females). Results: We found no group-by-sex effect on subregional volumetry. The left hippocampal cornu ammonis subfield 1 (CA1) volumes were lower in dependent cannabis users compared with non-dependent cannabis users (p<0.001, d=0.32) and with controls (p=0.022, d=0.18). Further, the left cornu ammonis subfield 3 (CA3) and left dentate gyrus volumes were lower in dependent versus non-dependent cannabis users but not versus controls (p=0.002, d=0.37, and p=0.002, d=0.31, respectively). All models controlled for age, intelligence quotient (IQ), alcohol and tobacco use, and intracranial volume. Amygdala volumetry was not affected by group or group-by-sex, but was smaller in females than males. Conclusions: Our findings suggest that the relationship between cannabis dependence and subregional volumetry was not moderated by sex. Specifically, dependent (rather than non-dependent) cannabis use may be associated with alterations in selected hippocampus subfields high in cannabinoid type 1 (CB1) receptors and implicated in addictive behavior. As these data are cross-sectional, it is plausible that differences predate cannabis dependence onset and contribute to the initiation of cannabis dependence. Longitudinal neuroimaging work is required to examine the time-course of the onset of subregional hippocampal alterations in cannabis dependence, and their progression as cannabis dependence exacerbates or recovers over time.

Episodic foresight is impaired following acute alcohol intoxication.

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.

Cognitive Reappraisal Impairs Negative Affect Regulation in the Context of Social Rejection for Youth With Early-Stage Borderline Personality Disorder.

Application of emotion regulation strategies might be susceptible to the context of social rejection for individuals with borderline personality disorder (BPD). This study compared the ability of 27 outpatient youths (15-25 years old) with early-stage BPD and 37 healthy controls (HC) to apply expressive suppression and cognitive reappraisal in standard and socially rejecting laboratory contexts. BPD youths were largely as able as HCs to regulate negative affect across instruction and contexts. However, cognitive reappraisal in the context of social rejection heightened BPD negative facial expression relative to HCs. Thus, while BPD emotion regulation ability was largely normative, cognitive reappraisal might be ineffective in the context of social rejection for this group, with social rejection acting as an accelerant that heightens the expression of negative affect. Given the common experience of perceived and actual social rejection for this group, clinicians should carefully consider treatments that include cognitive reappraisal strategies because they might be contraindicated.

Deficits in episodic future thinking following acute alcohol consumption.

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.

Concordance in salivary cortisol and subjective anxiety to the trier social stress test in social anxiety disorder.

BACKGROUND: Social anxiety disorder (SAD) is characterised by an excessive fear of negative social evaluation. There is a limited understanding of how individuals with SAD react physiologically and subjectively to social stress. METHOD: The Trier Social Stress Test (TSST), an acute social stress task, was completed by 40 SAD individuals (50% female) and 41 healthy controls (matched on age, sex, and education) to examine salivary cortisol and self-reported stress reactivity. Salivary cortisol concentrations and self-reported affect (anxiety, sadness, tiredness, withdrawal, and happiness) were assessed at baseline and across nine-time points during the TSST. RESULTS: Bayesian salivary cortisol analyses revealed no group differences in salivary cortisol levels at baseline or during the TSST, with results comparative after the removal of 17 cortisol non-responders (21%). Contrastingly, the groups significantly differed on self-reported affect. At baseline, the SAD group (vs. controls) reported heightened negative affect and diminished happiness. In response to the TSST, the SAD group (vs. controls) displayed greater negative affect reactivity and diminished happiness reactivity, and significantly higher rates of change in their anxiety and sadness over time. After accounting for differences in the temporal resolution of self-reported versus cortisol responses, a moderate positive association was found between salivary cortisol and anxiety reactivity to social stress that was comparable between the groups. CONCLUSIONS: Despite elevated subjective anxiety, our findings suggest concordance in psychobiological stress reactivity in SAD and healthy controls. We discuss the possibility of heightened subjective sensitivity to social evaluative stress as a core treatment target for SAD.

Prospective memory deficits following acute alcohol consumption.

BACKGROUND: Prospective memory is a critical neurocognitive capacity that refers to the ability to execute delayed intentions. To date, few studies have investigated the effects of acute alcohol consumption on prospective memory, and important questions remain about the mechanisms that might underpin acute alcohol-induced prospective memory impairment. AIMS: The current study sought to clarify the nature and magnitude of prospective memory difficulties following acute alcohol consumption and to test the degree to which any problems with prospective remembering might be a secondary consequence of broader cognitive impairment. This study also investigated whether there were potential sex differences. METHODS: In all, 124 healthy adult social drinkers were 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 and then asked to complete a measure of prospective memory. A broader neurocognitive test battery was also administered. RESULTS: Relative to the placebo condition, acute alcohol intoxication led to significant impairment on all prospective memory tasks, with effects mostly large in magnitude. These difficulties could not be explained by broader problems in retrospective memory, executive function or episodic future thinking. In addition, females recorded a higher blood alcohol concentration than males; however, no sex differences in prospective memory performance were identified following acute alcohol use. CONCLUSION: The results show that acutely, even a moderate dose of alcohol substantially impairs prospective memory function. These findings have potentially important implications for understanding many of the maladaptive behaviours associated with acute alcohol consumption.

Patterns of brain function associated with cannabis cue-reactivity in regular cannabis users: a systematic review of fMRI studies.

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.

Sex differences in the neuroanatomy of alcohol dependence: hippocampus and amygdala subregions in a sample of 966 people from the ENIGMA Addiction Working Group.

Males and females with alcohol dependence have distinct mental health and cognitive problems. Animal models of addiction postulate that the underlying neurobiological mechanisms are partially distinct, but there is little evidence of sex differences in humans with alcohol dependence as most neuroimaging studies have been conducted in males. We examined hippocampal and amygdala subregions in a large sample of 966 people from the ENIGMA Addiction Working Group. This comprised 643 people with alcohol dependence (225 females), and a comparison group of 323 people without alcohol dependence (98 females). Males with alcohol dependence had smaller volumes of the total amygdala and its basolateral nucleus than male controls, that exacerbated with alcohol dose. Alcohol dependence was also associated with smaller volumes of the hippocampus and its CA1 and subiculum subfield volumes in both males and females. In summary, hippocampal and amygdalar subregions may be sensitive to both shared and distinct mechanisms in alcohol-dependent males and females.

Implementation intentions and prospective memory function in late adulthood.

Prospective memory (PM) is a critically important component of memory that often declines in late adulthood. Implementation intentions, an encoding strategy, consisting of an explicit if-then "I will . . ." statement, has been effectively used to enhance older adults' prospective memory function. However, it remains to be established whether forming a mental representation of carrying out the task when forming the intention enhances these age effects, as well as whether the type of cue (event or time based) moderates age-related benefits. To test these questions, we randomly allocated 125 younger and 125 older adults to 1 of 5 conditions, in which they were directed to use different strategies when forming their PM intentions (Statement Only, Imagine in Game, Statement and Imagine Combined, Imagine in Daily Life, Control). The results indicated that use of the implementation intentions statement alone and in combination with forming a mental representation of carrying out the task substantially enhanced older adults' event- but not time-based PM. In addition, while the Statement Only condition reduced age-related difficulties for event-based tasks, the condition that combined this statement with visualization led to the greatest reduction in age effects. These data suggest that both rehearsing the implementations intention in the specific statement format combined with visualizing may be optimally effective for enhancing PM function in late adulthood but that the type of PM cue is an important moderator of these age effects. In addition to theoretical implications, these results may inform the refinement of interventions focused on enhancing PM function in late adulthood. (PsycInfo Database Record (c) 2020 APA, all rights reserved).