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.

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.

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.

Parkinson's disease disrupts the ability to initiate and apply episodic foresight.

OBJECTIVE: While Parkinson's disease is associated with impairments in many aspects of prospective cognition, no study to date has tested whether these difficulties extend to problems using episodic foresight to guide future-directed behavior. To provide the first examination of whether people with Parkinson's disease are impaired in their capacity to initiate and apply episodic foresight. METHOD: People with Parkinson's disease (n = 42), and a demographically matched neurotypical comparison group (n = 42) completed a validated behavioral assessment that met strict criteria for assessing episodic foresight (Virtual Week-Foresight), as well as a broader neurocognitive and clinical test battery. RESULTS: People with Parkinson's disease were significantly less likely than the comparison group to acquire items that would later allow a problem to be solved and were also less likely to subsequently use these items for problem resolution. These deficits were largely unrelated to performance on other cognitive measures or clinical characteristics of the disorder. CONCLUSIONS: The ability to engage in episodic foresight in an adaptive way is compromised in Parkinson's disease. This appears to be a stable feature of the disorder, and one that is distinct from other clinical symptoms and neurocognitive deficits. It is now critical to establish exactly why these difficulties exist and how they impact on real-life functional capacity.

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.

Episodic foresight in multiple sclerosis.

OBJECTIVE: Episodic foresight refers to the ability to imagine future scenarios and to then use this imaginative capacity to guide future-directed behavior. Multiple sclerosis (MS) is associated with deficits generating the phenomenological characteristics of future events (the imaginative component of episodic foresight), but no study to date has tested whether MS is also associated with deficits using episodic foresight to appropriately guide future-directed behavior. METHOD: Forty people with relapsing-remitting MS (RRMS) and 40 demographically matched healthy participants completed a validated measure that met strict criteria for assessing the functional application of episodic foresight, Virtual-Week Foresight (VW-Foresight). RESULTS: Overall, people with RRMS did not differ significantly relative to comparison participants in how likely they were to spontaneously acquire items that would later allow a problem to be solved and were also just as likely to subsequently use these items to solve the problem. However, the latter group difference was large in magnitude and just failed to attain significance. Higher levels of depression were significantly related to performance on this same "use" component of foresight in the RRMS group, and depressed RRMS participants were significantly impaired in this aspect of foresight relative to both healthy participants and nondepressed RRMS participants. The depressed MS subgroup also differed from the nondepressed subgroup in their ability to perform instrumental activities of daily living. CONCLUSIONS: People with RRMS who present with heightened levels of depressive symptomatology also appear to be at greater risk of experiencing specific problems with episodic foresight. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

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.

An old problem revisited: How sensitive is time-based prospective memory to age-related differences?

Prospective memory (PM) tasks that impose strong demands on strategic monitoring decline more in late adulthood relative to tasks dependent on more automatic cue detection processes. This finding has proven robust to numerous manipulations, with one exception: time-based PM. However, conventional time-based tasks may inadvertently present time-related yet still event-based cues. At the same time, prior studies have failed to consider whether time-based age differences vary according to the degree of deliberate strategic processing required to access these cues. In this study, 53 younger and 40 older participants completed three time-based PM conditions in which a response had to be executed when a sand timer completed a cycle. In one condition, this timer could only be accessed by explicit, deliberate monitoring (by pressing a specific key), in a second, it could also be accessed more perfunctorily (simply by altering ones' visual focus)-and in the third, could not be accessed at all (forcing participants to rely solely on internal temporal estimation processes). Negative age differences emerged in both conditions where participants were able to access the timer, but not in the condition where the timer was hidden. These data provide novel evidence of age-related preservation in at least some aspects of the temporal processing required to support time-based PM. They also suggest that younger and older adults can and do engage in monitoring when given this option, but that only the former group may be able to benefit, even when this monitoring can be conducted relatively perfunctorily. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Acting with the future in mind: Testing competing prospective memory interventions.

Prospective memory (PM) is a critical determinant of whether a person is able to lead an independent life. Because PM declines in late adulthood, an important question is therefore whether, and if so, which types, of PM interventions might lead to meaningful benefits. In the present study, we randomly assigned older adults to one of four conditions, in three of which participants received a structured PM intervention (Restorative, Compensatory, and Combined Restorative and Compensatory); the fourth was an Active Control condition. The results showed that there were significant gains on the PM training task used for both the Restorative and Combined conditions. We then analyzed change in PM tasks that were independent of the PM training task (Near Transfer). Only the Combined condition led to post-training improvement. Finally, we analyzed performance on measures of untrained cognitive abilities and everyday functioning: Far transfer effects were not evident for any intervention. These data align with prior literature in showing that interventions that target a single cognitive ability do not reliably generate far transfer effects, and additionally extend our understanding of these effects in two important ways. Firstly, they indicate that, even when the memory challenges that older adults are most concerned about are the direct target of restorative training, transfer effects to untrained cognitive domains may be difficult to achieve. Secondly, they indicate that for older adults whose primary goal is to enhance PM function, combining Restorative and Compensatory approaches is an effective approach. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Event-Based but Not Time-Based Prospective Memory Is Related to Oral Health in Late Adulthood.

BACKGROUND: Most evidence now indicates that cognitive function is related to poorer oral health in late adulthood, but that this relationship is not invariant across specific cognitive domains. Prospective memory (PM) is a core memory skill that refers to memory for future intentions and is known to be related to the formation of habits such as tooth flossing. However, the relationship between PM and oral health has been subject to only limited empirical study. OBJECTIVE: The two studies reported in this paper were designed to test whether PM is related to oral health in older adults of varying vulnerability status. METHODS: Study 1 sampled community-dwelling older adults (N = 172) living independently in the community; Study 2 sampled older adults living in a retirement village (N = 32). Participants in both studies were asked to complete a behavioural measure of PM, with their oral health indexed via self-report (Study 1) or an objective oral health exam (Study 2). RESULTS: In both studies, relationships emerged between event-based PM and oral health, with Study 2 showing that these relationships were specific to oral health measures of plaque and calculus. CONCLUSIONS: Older adults are particularly vulnerable to dental pathology, with important implications for their broader health and well-being. By showing that there is a relationship between oral health and a particular type of PM, this work will have potential implications for the development of more effective interventions focused on enhancing oral health outcomes in this group, such as those focused on strengthening habit formation.

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).

Differences in time-based task characteristics help to explain the age-prospective memory paradox.

Prior prospective memory (PM) research shows paradoxical findings-young adults outperform older adults in laboratory settings, but the reverse is found in naturalistic settings. Moreover, young-old outperform old-old adults in laboratory settings, but show no age differences in naturalistic settings. Here we highlight how time-based task characteristics have differed systematically between studies conducted in laboratory (time-interval cues) and naturalistic settings (time-of-day cues) and argue that this apparent paradox is a function of comparing disparate task types. In three experiments, we tested this hypothesis using analogous paradigms across settings, with event-based, time-of-day, and time-interval cued PM tasks. Experiment 1 compared young (n = 40) and older (n = 53) adults on a laboratory paradigm that measured PM tasks embedded in a virtual, daily life narrative; and on a conceptually parallel paradigm using a customized smartphone application (MEMO) in actual daily life. Results revealed that on the MEMO, older adults outperformed young adults on the time-of-day tasks but did not differ on the time-interval or event-based task. In contrast, older adults performed worse than young adults in the laboratory. Experiment 2 compared PM performance in young-old (n = 64) and old-old (n = 40) adults using the same paradigms. Young-old outperformed old-old adults in the laboratory; however, group differences were not evident in daily life. Experiment 3 compared young (n = 42) and older (n = 41) adults, and largely replicated the findings of Experiment 1 using a more demanding version of MEMO. These findings provide novel and important insights into the limiting conditions of the age-PM paradox and the need for a finer theoretical delineation of time-based tasks.

Rapid facial mimicry responses are preserved in youth with first presentation borderline personality disorder.

BACKGROUND: Empathy is a complex and multifaceted construct comprising cognitive and affective components. Abnormal empathic responses are implicated in borderline personality disorder (BPD). Specifically, unconscious motor mimicry (a primitive component of affective empathy evident from infancy) is theorized to be heightened and to contribute to the heightened emotional contagion often seen in people with BPD. Yet, no study has directly tested whether abnormally heightened unconscious motor mimicry is associated with BPD features or whether this is present early in the course of BPD. METHODS: In the present study, facial electromyography was used to assess the rapid facial mimicry responses (a form of unconscious motor mimetic responding) of 32 outpatient youths (aged 15-25 years) with early stage BPD features and 47 demographically matched healthy control participants (HC). RESULTS: The results showed no group differences in rapid facial mimetic responses to either positive (happy) or negative (angry) facial emotions. LIMITATIONS: Co-occurring psychopathology and the potential impact of state affect on rapid facial mimicry were considered and discussed. CONCLUSIONS: These data indicate that there is no evidence for abnormally heightened rapid motor mimicry in youth early in the course of BPD, suggesting that rapid facial mimicry is preserved in this group. It is thus unlikely that abnormally heightened unconscious simulation contributes to heightened emotional contagion in youth with first presentation BPD. Future research should explore alternative mechanisms for this phenomenon and also whether abnormalities in motor mimetic responses are evident in later stages of the disorder.

Task characteristics influence facial emotion recognition age-effects: A meta-analytic review.

Relative to their young counterparts, older adults are poorer at recognizing facial expressions. A 2008 meta-analysis of 17 facial emotion recognition data sets showed that these age-related difficulties are not uniform. Rather, they are greatest for the emotions of anger, fear, and sadness, comparative with happiness and surprise, with no age-effect found for disgust. Since then, there have been many methodological advances in assessing emotion recognition. The current comprehensive meta-analysis systematically tested the influence of task characteristics (e.g., photographs vs. videos). The meta-analysis included 102 data sets that compared facial emotion recognition in older and young adult samples (N = 10,526). With task type combined, the pattern of age-effects across emotions was mostly consistent with the previous meta-analysis (i.e., largest age-effects for anger, fear, sadness; no effect for disgust). However, the magnitude and direction of age-effects were strongly influenced by elements of task design. Specifically, videos produced relatively moderate age-effects across all emotions, which indicates that older adults may not exhibit a positivity effect for facial emotion recognition. For disgust recognition, older adults demonstrated superior accuracy to young adults for the most common image set (Pictures of Facial Affect). However, they were poorer than young adults at recognizing this emotion for all other stimulus formats and image sets, which suggests that they do not retain disgust recognition. We discuss the implications that such diversity in the age-effects produced by different facial emotion recognition task designs has for understanding real-world deficits and task selection in future emotion recognition studies. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

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.

Social cognition impairments in long-term opiate users in treatment.

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.

A meta-analytic review of prospection deficits in Parkinson's disease.

Parkinson's disease (PD) is one of the most common neurodegenerative disorders, and is associated with prominent motor deficits. However, neurocognitive impairment is also a common clinical feature that can contribute greatly to the overall disease burden. In the current study, a meta-analysis was conducted to gain a clearer understanding of how PD affects one of the most functionally important domains of cognition: prospection. The results indicate that, relative to controls, PD is associated with a large deficit in the capacity to engage in planning (g = -0.81, K = 25) and a moderate-sized deficit in prospective memory (g = -0.57, K = 16). Sub-analyses indicated that these deficits are evident for both time and event-based prospective memory, as well as for prospective memory tasks that have relatively limited ecological validity. Significant impairment was also evident for both medicated and non-medicated PD sub-groups, but for planning, these deficits were substantially greater in the unmedicated sub-group. The theoretical and practical implications of these findings are discussed.

A comparison of different types of prospective memory reminders in schizophrenia.

People with schizophrenia often experience difficulties with prospective memory (PM), but few empirical studies have directly compared the effectiveness of different types of reminders in remediating these difficulties. In the present study, two distinct types of reminders were compared to a standard (no reminder) condition in outpatients with schizophrenia (n = 30) and controls (n = 30). Using an adapted version of the well-validated laboratory PM measure, Virtual Week, participants were asked to complete three different conditions (counterbalanced), in which they were (i) provided with access to self-initiated reminders, (ii) provided with experimenter-initiated reminders, and (iii) completed a standard (no-reminder) condition. Both groups benefited from the provision of reminders, but self-initiated reminders were the most beneficial, particularly for time-based tasks. These data align with a broader literature that shows PM can be enhanced by the use of reminders. However, it extends this literature in an important way by showing that these benefits are equivalent for people with schizophrenia, and may be greatest where access to reminders is self-initiated. The implications of these data for the development of rehabilitative interventions are discussed.

The effects of licit and illicit recreational drugs on prospective memory: a meta-analytic review.

RATIONALE: There are no recent reports summarising the magnitude of prospective memory (PM) impairments in recreational drug users. OBJECTIVE: We performed a meta-analysis of studies (with a parallel group design) examining PM performance in users of common recreational drugs (including alcohol and tobacco) who were not intoxicated during testing. Studies were also evaluated for the presence of methodological bias. METHODS: Twenty-seven studies were included in the meta-analysis following literature searches of MEDLINE, EMBASE and PsycINFO. Effect sizes (standardised mean difference; SMD) were calculated separately for the effects of alcohol, cannabis, ecstasy, methamphetamine and tobacco use. The influences of drug use and study characteristics on effect sizes were explored using meta-regressions. Sources of study bias were also assessed. RESULTS: Heavy drinkers and regular drug users tended to perform worse than controls on event and time-based PM tasks. Effect sizes (standardised mean differences; SMDs) for event-based PM impairment across the different drug-using groups/heavy drinkers ranged between - 1.10 and - 0.49, with no 95% CI crossing 0.00. SMDs for time-based PM ranged between - 0.98 and - 0.70. Except for the CIs associated with the ES for smokers' time-based PM performance, no CIs crossed 0.00. CONCLUSIONS: Although all drug-using groups showed moderate-large impairments in event and time-based PM, effect sizes had low precision and moderate-high levels of heterogeneity. In addition, several methodological and reporting issues were identified in the majority of studies. As such, considerable uncertainty remains regarding the role of confounds and the magnitude of PM impairments in non-intoxicated recreational drug users.