Biological sex and hormonal contraceptive associations with drug cue reactivity in cannabis use disorder.

Biological sex differences in Cannabis Use Disorder (CUD) progression, cannabis withdrawal severity, and pharmacotherapy response have been reported, suggesting that CUD mechanisms may differ by sex. Drug cue reactivity is an established predictor of drug use behavior, but the literature on sex differences in drug cue reactivity is mixed, including in CUD. One possible moderator of sex differences in drug cue reactivity is hormonal contraceptive (HC) use. The aim of the present study was to test whether sex differences in neural cannabis cue reactivity and craving varied by female HC use in a CUD sample. As part of a larger study, 152 adults reporting frequent cannabis use completed a drug cue reactivity task during electrocenphalogram recording. Late positive potential (LPP) amplitude modulation by cannabis cues was used to measure neural cue reactivity. Craving after the cue reactivity task was also assessed. Males (n = 74) and naturally-cycling females (n = 26), who did not differ from each other, showed significantly greater LPP enhancement to cannabis vs. neutral cues compared to HC-using females (n = 52), an effect mostly driven by neutral cues. Craving was significantly higher in naturally-cycling but not HC-using females compared to males, but only in covariate-unadjusted analyses. Exploratory analyses of HC and menstrual phase characteristics indicate a progesterone-related mechanism may underlie HC effects on cannabis cue reactivity. The present study's results suggest that mixed findings on drug cue reactivity sex differences may be due to variability in HC use, which has implications for sex-specific models of CUD progression and treatment.

Decomposing the late positive potential to cannabis cues in regular cannabis users: A temporal-spatial principal component analysis.

Cannabis use disorder (CUD) is increasing in the United States, yet, specific neural mechanisms of CUD are not well understood. Disordered substance use is characterized by heightened drug cue incentive salience, which can be measured using the late positive potential (LPP), an event-related potential (ERP) evoked by motivationally significant stimuli. The drug cue LPP is typically quantified by averaging the slow wave's scalp-recorded amplitude across its entire time course, which may obscure distinct underlying factors with differential predictive validity; however, no study to date has examined this possibility. In a sample of 105 cannabis users, temporo-spatial Principal Component Analysis was used to decompose cannabis cue modulation of the LPP into its underlying factors. Acute stress was also inducted to allow for identification of specific cannabis LPP factors sensitive to stress. Factor associations with CUD severity were also explored. Eight factors showed significantly increased amplitudes to cannabis images relative to neutral images. These factors spanned early (~372 ms), middle (~824 ms), and late (>1000 ms) windows across frontal, central, and parietal-occipital sites. CUD phenotype individual differences were primarily associated with frontal, middle/late latency factor amplitudes. Acute stress effects were limited to one early central and one late frontal factor. Taken together, results suggest that the cannabis LPP can be decomposed into distinct, temporal-spatial factors with differential responsivity to acute stress and CUD phenotype variability. Future individual difference studies examining drug cue modulation of the LPP should consider (1) frontalcentral poolings in addition to conventional central-parietal sites, and (2) later LPP time windows.

Physiological stress modulation of neural drug cue reactivity in cannabis use disorder.

OBJECTIVE: Rates of daily cannabis use and cannabis use disorder (CUD) are increasing in the United States. Prominent addiction theories suggest that stress potentiation of drug cue incentive salience is a central feature of disordered versus recreational drug use, which has been corroborated using a neurophysiological index of drug cue incentive salience (i.e., the late positive potential [LPP]) in adults who regularly use cannabis. However, the mechanism through which acute stress potentiates the cannabis LPP in CUD is unclear. METHOD: To address this gap, cannabis LPPs were measured before and after a stress induction in 95 adults who regularly use cannabis. Physiological (hypothalamic-pituitary-adrenal [HPA] axis, heart rate, skin conductance) and subjective stress reactivity were also measured. RESULTS: Based on prior work, we hypothesized that cortisol stress reactivity would predict poststress cannabis LPP enhancement in more severe CUD. The hypothesis was supported and specific to HPA-axis versus autonomic or subjective stress reactivity. CONCLUSIONS: Acute stress potentiation of the cannabis LPP, likely via HPA-axis activation, may be a biomarker of heavy/disordered cannabis use in adults who regularly use cannabis. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Neurophysiological error processing and addiction self-awareness correlates of reduced insight in cannabis use disorder.

BACKGROUND AND AIMS: Cannabis use disorder (CUD) prevalence has increased, while perceived risks of cannabis use and CUD treatment need have decreased. Chronic cannabis use may also impair the neural and behavioral mechanisms of insight, further hampering treatment-seeking. This study aimed to measure whether CUD is characterized by reduced self-monitoring in drug-related contexts (objectively-assessed insight), subserved by functional neural abnormalities in error-processing and manifested clinically as decreased awareness of the need to change. DESIGN: Case-control laboratory study was used. SETTING: University setting was in Alabama, USA. PARTICIPANTS: There were 42 CUD participants and 47 age-, sex-, and nicotine use-matched controls. MEASUREMENTS: Participants completed a probabilistic choice task, adapted for the first time for CUD, in which they selected pleasant, unpleasant, neutral, and cannabis-related images according to their preference. Reduced versus accurate insight was operationalized as the correspondence between self-reported and actual most chosen image type. Neurophysiological error-processing during an inhibitory control task was recorded using electroencephalography. Participants with CUD completed measures of cannabis problem recognition and motivation to change. FINDINGS: Compared with controls, the CUD group made significantly more cannabis selections on the choice task (mean difference [MD] = 8.11, 95% confidence interval [CI] [4.88 11.35], p < 0.001) and had significantly reduced insight into cannabis choice (odds ratio [OR] = 9.69, 95% CI [1.06 88.65], p = 0.04). CUD participants with reduced insight on the choice task had significantly decreased neurophysiological reactivity to errors on the inhibitory control task (error-related negativity) compared with CUD participants with accurate insight (MD = 2.64 µV, 95% CI [0.74 µV 4.54 µV], p = 0.008) and controls (MD = 4.05 µV, 95% CI [1.29 µV 6.80 µV], p = 0.005). Compared with CUD participants with accurate insight on the choice task, CUD participants with reduced insight reported significantly less agreement that they had a cannabis problem (MD = -5.06, 95% CI [-8.49-1.62], p = 0.003). CONCLUSIONS: People with CUD who show reduced insight on a drug-related choice task may also have decreased early neural error-processing and less cannabis problem recognition.

Impact of a brief distress intolerance intervention on acute stress modulation of response inhibition neurophysiology in cannabis use disorder.

BACKGROUND: The prevalence of cannabis use in the US has increased within the past two decades. Moreover, cannabis use disorder (CUD) is associated with significant disability, but the underlying neural mechanisms of CUD are unclear. Distress intolerance (DI), a psychological risk factor for CUD, may confer risk in part via impaired inhibitory control (IC) capacity during acute stress. DI and cannabis use problems have been associated with altered N2 amplitude, an IC-related event-related potential, in prior cross-sectional studies, but whether altered N2 is a state marker of CUD severity, a pathoplastic factor responsive to intervention and predictive of CUD symptom change over time, or an enduring trait-like vulnerability is unclear. In this secondary analysis, we tested the impact of a DI-targeted intervention on acute stress-related modulation of the N2 and whether pre-intervention N2 predicted CUD symptom change through follow-up. METHOD: Sixty participants were randomly assigned to a DI-targeted or control intervention. Participants completed an IC task before and after a stress induction at pre- and post-intervention lab visits while EEG activity was recorded. RESULTS: The DI intervention did not alter the N2 compared to a control intervention. Pre-intervention post-stress IC-related N2 was associated with worse CUD severity but did not predict changeover time. CONCLUSION: Findings are consistent with blunted N2 after acute stress acting as a stable marker of CUD severity rather than a pathoplastic factor predictive of CUD trajectory. Future research should investigate whether stress-related blunting of N2 is a consequence of severe CUD or a pre-existing vulnerability.

Temporal stability of neurophysiological drug cue reactivity before and after acute stress in cannabis users: A test of incentive sensitization.

BACKGROUND: Given increasing rates of Cannabis Use Disorder (CUD), objective measures are needed that can reliably index risk and track cannabis use progression. Based on incentive sensitization models, neurophysiological reactivity to cannabis cues, measured with the electroencephalography-recorded late positive potential (LPP), may be a candidate biomarker. To serve as such, the cannabis cue-elicited LPP must demonstrate adequate retest reliability and sensitivity to cannabis use change. Moreover, incentive sensitization theory suggests that state-level contextual variables, such as acute stress, can impact drug cue reactivity. Therefore, the present study evaluated the three-month retest reliability of the cannabis cue-elicited LPP, recorded before and after a laboratory stress induction, as well as its sensitivity to cannabis use change. METHOD: Cannabis and neutral cue-elicited LPPs were measured in 102 adults reporting frequent cannabis use (86 % with current CUD) before and after an acute stress induction at two lab visits three-months apart. Physiological and subjective stress reactivity were also measured. RESULTS: Manipulation checks confirmed expected cannabis cue and acute stress effects. Cannabis cue-elicited LPP amplitudes showed significant three-month retest reliability of poor-to-fair through moderate-to-good size. Change in cannabis use frequency significantly predicted change in cannabis cue-elicited LPP amplitudes, particularly at post-stress. CONCLUSION: Consistent with incentive sensitization models of addiction, the cannabis cue-elicited LPP demonstrated trait-like, moderate three-month stability and responsivity to change in cannabis use behavior. Greater predictive validity of the post-stress LPP may arise through kindling effects of acute stress on incentive salience-related neural activity, which should be explored in future studies.

Impact of acute stress on neural indices of positive and negative reinforcement processing in cannabis users.

OBJECTIVE: Chronic cannabis use is maintained in part through dysregulated stress and reward response systems. Specifically, stress-related negative affect is thought to act as a salient motivator for chronic substance use. Models of addiction posit that the transition from positive to negative reinforcement motives for substance use is a key mechanism of disordered use. However, research in substance-using samples has not assessed stress-related neural processing of both positive and negative reinforcement. METHOD: Therefore, the present study utilized laboratory stress induction to examine how stress affects the reward positivity, an event-related potential sensitive to both positive (RewP) and negative (relief-RewP) reinforcement, in 87 cannabis users (58.10% female, Mage = 19.40) varying in cannabis use disorder (CUD) severity and, as part of larger study aims, history of traumatic brain injury (TBI). We predicted greater CUD severity would be associated with a blunted RewP and enhanced relief-RewP, particularly after stress induction, independent of TBI status. RESULTS: Findings indicated that CUD severity was not associated with RewP/relief-RewP amplitude regardless of acute stress. Exploratory analyses revealed, however, that among those with history of TBI +, CUD severity was associated with greater stress-elicited blunting of the RewP and enhancement of the relief-RewP. CONCLUSION: Although initial findings contradict current allostatic models of addiction, exploratory findings suggest that history of TBI, and potentially other confounding variables related to increased risk of TBI experience, may influence the extent to which stressful experiences modulate the neurophysiology of both positive and negative reinforcement reward processing in CUD. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Impact of a computerized distress intolerance intervention on electrocortical reactivity to cannabis and threat cues: A randomized controlled trial.

OBJECTIVE: Given increasing rates of daily cannabis use and Cannabis Use Disorder (CUD) in the United States, it is imperative to understand CUD mechanisms in high-risk groups. Cannabis users with high distress intolerance (DI) are at elevated risk for severe and chronic CUD, but neural mechanisms linking CUD and DI are unknown. Cross-sectional data suggests that acute stress modulation of the cannabis and threat cue-elicited late positive potential (LPP), a neurophysiological marker of motivated attention, are possible mechanisms. However, longitudinal research is needed to clarify the roles of these elicited LPPs in CUD maintenance. METHOD: Sixty cannabis users with high DI were randomized a brief computerized intervention targeting DI or a control intervention. Elicited LPPs were measured before and after a stressor at baseline and postintervention. Intervention effects on stress modulation of the cannabis and threat LPPs, as well as their prospective associations with CUD, were assessed. RESULTS: Elicited LPPs did not significantly change in either intervention group. Acute stress enhancement of the cannabis LPP predicted more severe CUD and greater chronicity at 4-month follow-up. CONCLUSIONS: Cannabis and threat LPPs were not altered by a brief DI intervention despite improvement in DI and cannabis use outcomes. Given that acute stress enhancement of the cannabis LPP predicted poorer CUD outcome, it may be a fruitful intervention target in distress intolerant cannabis users. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Thwarted belongingness predicts greater neural reactivity to a novel social exclusion image set: Evidence from the late positive potential.

INTRODUCTION: Thwarted belongingness (TB) is among the most well-researched risk factors for suicidal ideation (SI). Yet, there is little research examining neural mechanisms underlying this construct. The present study used a novel social exclusion image set in concert with the late positive potential (LPP) to test the role of neural reactivity social exclusion in TB and SI. METHODS: Participants (n = 243) were recruited based on elevated suicide risk and completed an emotional picture viewing task. The LPP was used to index neural reactivity to a novel set of social exclusion images and international affective picture system (IAPS) neutral, positive, and negative images. RESULTS: Greater TB predicted a larger social exclusion ΔLPP (social exclusion LPP relative to neutral LPP) and social exclusion LPP even when accounting for SI, biological sex, age, negative affect, and perceived burdensomeness. Moreover, the social exclusion LPP was uniquely related to TB beyond the LPP to other images. Last, a larger social exclusion LPP predicted greater SI via elevations in TB. CONCLUSION: Reactivity to social exclusion stimuli may play an important role in SI via elevated TB, but not perceived burdensomeness. Future research should further explore the neural mechanisms underlying other IPT constructs.

Psychometric properties of the late positive potential in combat-exposed veterans.

Trauma exposure is prevalent, associated with multiple forms of psychopathology, and thought to alter the neurobiological substrates of threat processing. The late positive potential (LPP) is an event-related potential (ERP) that may be a clinically useful probe of the neurobiology of threat processing. Despite evidence that combat-exposed veterans exhibit aberrant threat modulation of the LPP, no studies to date have tested the psychometric properties of the LPP in combat trauma-exposed, symptomatic veterans. The primary aim of the current study was to evaluate the reliability (internal consistency, retest reliability) and convergent validity of LPP modulation by threatening faces and scenes in two common tasks among combat-exposed veterans. Participants included 82 combat-exposed veterans who completed face-matching and emotion regulation tasks during EEG recording at baseline and twelve weeks. Internal consistencies of the early LPP time windows (<1000 ms) were acceptable in both tasks, whereas they were poor in late time windows (>1000 ms). Twelve-week retest reliabilities were fair for the early window LPPs to threatening scenes and fear faces, as well as in the late time window for fear faces. Reliabilities were better for individual condition compared to difference scores. Finally, LPPs modulated by threatening scenes and faces were unrelated. Together, these results suggest that the LPPs to threatening scenes and faces reflect distinct forms of threat processing in combat-exposed veterans, and their reliabilities for the early window indicate potential clinical utility in this population.

Development and validation of a cannabis cue stimulus set.

Regular cannabis use and cannabis use disorder (CUD) have become increasingly prevalent in the United States over the past two decades. Theory and empirical data suggest that the incentive salience of cannabis cues is important to the development and chronicity of CUD. Cannabis cue incentive salience is often assessed with a cannabis cue reactivity paradigm wherein cannabis-related and neutral images are presented. However, prior cannabis cue reactivity studies have been limited by the use of heterogeneous stimuli that were not properly characterized across motivational/affective characteristics, physical image attributes, or non-cannabis-related salient image features (e.g., human presence, face visibility). In order to increase standardization and flexibility of future cannabis cue reactivity tasks, the aim of the present study was to develop and validate a cannabis cue and matched neutral image database comprised of motivational/affective ratings as well as physical image attributes. 234 regular cannabis users varying in primary use method (i.e., bowl, blunt/joint, bong, vaporizer) made motivational (i.e., urge to smoke cannabis) and affective (i.e., arousal, valence) ratings of cannabis-related and neutral images matched on salient, non-cannabis-related features. Physical features (hue, saturation, value) of each image were also analyzed. Motivational/affective ratings of cannabis-related and neutral images differed as expected, and cannabis use frequency and cannabis craving correlations with cannabis image ratings generally supported stimulus validity. Motivational/affective ratings did not significantly differ across cannabis use method-specific images. This database may be a useful tool for future behavioral and neuroscience research on cannabis cue reactivity.

Impact of a computerized intervention for high distress intolerance on cannabis use outcomes: A randomized controlled trial.

OBJECTIVE: Prevalence of regular cannabis use and cannabis use disorder (CUD) have increased in the past two decades, but treatment-seeking is low and extant brief interventions do not target causal risk factors implicated in etiological models of addiction. Elevated distress intolerance (DI) is one risk factor that has been empirically linked with greater CUD severity and maintenance in regular users, but, to our knowledge, research has never targeted it in a brief intervention among cannabis users with CUD or at high risk. The current RCT evaluated the impact of a DI intervention (i.e., Distress Tolerance Intervention [DTI]) compared to a healthy habits control intervention (i.e., Healthy Video Control [HVC]) on DI and cannabis use outcomes. METHOD: We randomized cannabis users with high DI (N = 60) to the DTI or HVC condition and they received two computerized intervention sessions. We assessed relief cannabis craving at pre- and post-treatment; and we assessed DI, cannabis use coping motives, use-related problems, and use frequency at pre- and post-treatment as well as one- and four-month follow-ups. We assessed CUD symptoms via interviews at pre-treatment and four-month follow-up. RESULTS: Significant, durable reductions in DI and all cannabis use outcomes occurred in both conditions. Compared to the HVC condition, the DTI led to greater reductions in use frequency during the treatment period. Reductions in self-reported DI were correlated with reductions in coping motives and CUD symptoms. CONCLUSION: The DTI's impact on all outcomes was largely comparable to the control condition, though it may have utility as an adjunctive intervention.

Distress Tolerance as a Familial Vulnerability for Distress-Misery Disorders.

Low perceived distress tolerance (DT), a trait-like individual difference factor reflecting one's perceived ability to withstand aversive affective states, has been linked with current internalizing and substance use disorders (SUDs). However, perceived DT has not been systematically evaluated as a familial, transdiagnostic vulnerability factor for internalizing and SUDs. The current study tested whether perceived DT runs in families and whether it is reduced among individuals with versus without remitted internalizing/SUD psychopathology. Perceived DT and internalizing/SUDs were measured in 638 individuals (nested within 256 families). Analyses also adjusted for the effects of neuroticism to test whether DT was a specific vulnerability factor independent of temperamental negative affect. Analyses revealed that perceived DT was lower in individuals with remitted distress (i.e., major depression, generalized anxiety disorder, posttraumatic stress disorder) but not fear disorders (i.e., panic disorder, social anxiety disorder, specific phobia, obsessive-compulsive spectrum disorders) relative to healthy controls, and the effect of distress-misery disorder history remained significant when adjusting for neuroticism. Perceived DT was not significantly different among individuals with versus without a remitted SUD. There were no effects for comorbid SUD and distress-misery disorders. Finally, perceived DT was also significantly correlated within families, suggesting that it runs in families. Overall, results suggest that independent of neuroticism, low perceived DT is a familial vulnerability for distress (but not fear or substance use) disorders.

Nonlinear relations between post-traumatic stress symptoms and electrocortical reactivity during emotional face processing in combat-exposed veterans.

Combat-related post-traumatic stress symptoms (PTSS) are prevalent among recently deployed veterans, making identification of biomarkers of PTSS in this population a public health priority. Given the link between threat processing neurobiology and PTSS, the threat-related late positive potential (LPP), an ERP reflective of attentional processing sensitive to emotion and its regulation, may have utility as a cost-effective biomarker. Existing PTSS/threat-related LPP findings are mixed, possibly due to variability in PTSS across samples, but this has never been explicitly tested. To address this gap, LPP amplitudes to angry, fearful, and happy emotional face stimuli were recorded among 81 combat-exposed veterans at a VA hospital. A quadratic relationship between self-reported PTSS and LPP amplitude modulation by angry faces emerged such that greater PTSS was related to a decreased LPP response to angry faces among veterans with subthreshold PTSD and an enhanced LPP response to angry faces among veterans with probable PTSD. These results suggest that prior mixed findings may be due to variability in PTSS severity. In addition, exploratory moderation analysis revealed that PTSS was positively associated with late LPP modulation for veterans reporting low cognitive reappraisal use and negatively associated with late LPP modulation for veterans reporting high cognitive reappraisal use. All results were specific to the 1,000-3,000 ms LPP time window. Thus, the functional nature of LPP modulation by direct threat cues may depend upon PTSS severity and/or related variables (e.g., cognitive reappraisal utilization).

Impaired Conflict Detection Differentiates Suicide Attempters From Ideating Nonattempters: Evidence From Event-Related Potentials.

BACKGROUND: Existing research suggests that inhibitory control deficits may differentiate individuals who think about suicide from those who make a suicide attempt. However, no available research, to our knowledge, has examined whether suicidal behaviors are associated with disruptions in the ability to determine when inhibitory control is needed or the ability to engage inhibition of an inappropriate or maladaptive behavior. The current study utilized event-related potentials to investigate specific facets of inhibitory control and their associations with suicide attempt history among a heterogeneous clinical sample who reported current suicidal ideation. METHODS: Ideators with no past suicide attempts (n = 46) and those with a history of suicide attempts (n = 22) completed a complex go/no-go task. Raw waveforms and temporospatial principal components analysis were used to index conflict detection (i.e., ΔN2) and motor inhibition (i.e., ΔP3a). Behavioral performance indices were also examined. RESULTS: Suicide attempters exhibited deficits in detecting the need for inhibitory control, as indexed by a more positive ΔN2 factor, than did ideating nonattempters, even when accounting for psychiatric comorbidity and age. However, these results only emerged in the principal components analysis-derived latent factor. No differences in behavioral performance or ΔP3a amplitude emerged. CONCLUSIONS: A relative inability to detect when to inhibit a maladaptive behavior, but not the ability to engage motor inhibition to stop that behavior, may distinguish suicide ideators who make a suicide attempt from those who do not. However, future research with prospective designs are needed to determine how conflict detection deficits may contribute to the emergence or escalation of a suicidal crisis.

Differentiating suicide attempts and suicidal ideation using neural markers of emotion regulation.

BACKGROUND: Theories of suicide posit distinct etiological pathways for suicide attempts (SA) and suicidal ideation (SI) that are marked, in part, by disruptions in the ability to regulate reactions to threat/mutilation and interpersonally-relevant emotional stimuli. However, little research has specifically tested these associations. To address this gap, the present study extracted the Late Positive Potential (LPP) during an emotion regulation task to evaluate the independent associations that SA history and SI share with initial responsivity to, and regulation of, these distinct emotional contents. METHODS: A clinical sample (N = 257) were recruited based on elevations in suicide risk factors. Participants completed a picture viewing and regulation task that included threat/mutilation, reward, and neutral images from the International Affective Picture System. Immediately prior to picture onset, participants were instructed to passively view the image, increase their emotional reaction to the image, or decrease their emotional reaction to the image. RESULTS: Differential patterns of LPP amplitudes only emerged in the context of attempts to regulate emotional responses such that SA history predicted a superior ability to volitionally mitigate responses to threat/mutilation while SI was related to a worse ability to increase responses to reward. Effect sizes were in the small and small-to-medium range. LIMITATIONS: The present data were cross-sectional and included low trial counts. CONCLUSIONS: Taken together, these findings support existing theories of suicide suggesting that distinct mechanisms underlie suicidal thoughts and behaviors. Future research should seek to determine if these mechanisms may serve as a viable intervention targets.

Distress intolerance moderation of motivated attention to cannabis and negative stimuli after induced stress among cannabis users: an ERP study.

Prevalence of cannabis use is increasing, but many regular users do not develop cannabis use disorder (CUD); thus, CUD risk identification among current users is vital for targeted intervention development. Existing data suggest that high distress intolerance (DI), an individual difference reflective of the ability to tolerate negative affect, may be linked to CUD, but no studies have tested possible neurophysiological mechanisms. Increased motivated attentional processing of cannabis and negative emotional stimuli as indexed by neurophysiology [i.e. the late positive potential (LPP)], particularly during acute stress, may contribute to CUD among high DI users. Frequent cannabis users with high (n = 61) and low DI (n = 44) viewed cannabis, negative, and matched neutral images during electroencephalography (EEG) recording before and after a laboratory stressor. Cannabis cue-elicited modulation of the 1000- to 3000-milliseconds LPP was larger in high DI users at post-stressor only, although the effect was only robust in the 1000- to 2000-milliseconds window. Further, modulation magnitude in the high DI group covaried with stress-relief craving and some CUD indices in the 400- to 1000-milliseconds and 1000- to 3000-milliseconds windows, respectively. No significant effects of DI on negative stimuli-elicited LPP modulation were found, although inverse associations with some CUD indices were observed. Finally, exploratory analyses revealed some evidence for DI moderation of the relation between subjective stressor reactivity and negative stimuli-elicited LPP modulation such that greater stressor reactivity was associated with blunted versus enhanced modulation in the high and low DI groups, respectively. Negative and cannabis stimuli-elicited LPP modulation appear to index distinct, CUD-relevant neural processes in high DI cannabis users.

Interactive effects of cumulative lifetime traumatic brain injuries and combat exposure on posttraumatic stress among deployed military personnel.

Growing research links Traumatic Brain Injury (TBI) with greater posttraumatic stress disorder (PTSD) symptoms. Much of this research has focused on the influence of the presence or severity of a single TBI while neglecting the potential cumulative effects of multiple TBIs incurred across an individual's lifetime on combat-related PTSD. The present study addressed this gap using a sample of 157 military service members and 4 civilian contractors who underwent structured TBI interviews at a military hospital in Iraq and completed the Combat Experiences Scale (CES) and Posttraumatic Checklist - Military (PCL-M). Results indicated that a greater number of lifetime TBIs were associated with greater PTSD symptoms when accounting for the presence and severity of a recent, deployment-related TBI. Additionally, a significant interaction of number of lifetime TBIs and combat exposure emerged, indicating that exposure to combat yielded greater PTSD symptoms among those with multiple lifetime TBIs compared to those with one or zero lifetime TBIs. These data suggest that incurring multiple TBIs may amplify the link between combat exposure and PTSD and underscore the need to screen for lifetime TBI history.

Gender differences in the relation between the late positive potential in response to anxiety sensitivity images and self-reported anxiety sensitivity.

Anxiety sensitivity (AS), or the fear of anxious arousal, is a transdiagnostic risk factor predictive of a wide variety of affective disorders. Whereas AS is widely studied via self-report, the neurophysiological correlates of AS are poorly understood. One specific issue this may help resolve is well-established gender differences in mean levels of AS. The current study evaluated late positive potential (LPP) for images designed to target AS during an emotional picture viewing paradigm. Structural equation modeling was used to examine convergent and discriminant validity for self-report AS and the LPP for AS images, considering gender as a potential moderator. Analyses were conducted in an at-risk sample of 251 community adults (M age = 35.47, SD = 15.95; 56.2% female; 53.6% meeting for a primary Axis I anxiety or related disorder). Findings indicated that the AS image LPP was significantly, uniquely associated with self-report AS, controlling for the LPP for unpleasant images, in females only. Mean levels of AS self-report as well as the AS image LPP were higher in females than in males. These findings provide initial support for the AS image LPP as a useful neurophysiological correlate of AS self-report in females. These findings also provide support for a biological cause for gender differences in AS. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Distress intolerance moderation of neurophysiological markers of response inhibition after induced stress: Relations with cannabis use disorder.

Cannabis use is prevalent but only a minority of regular users develop cannabis use disorder (CUD); thus, CUD risk identification among current cannabis users is vital for targeted intervention development. Existing data suggest that high distress intolerance (DI), an individual difference reflective of the ability to withstand negative affect, is linked to CUD, possibly via stress-elicited impairment of response inhibition but this has never been explicitly tested. Frequent cannabis users with high and low DI completed a go/no-go task during EEG recording before and after a laboratory stressor. Relations between DI, cannabis use-related problems, and behavioral as well as neurophysiological markers of response inhibition functioning were assessed. DI significantly moderated the effect of the stressor on the conflict-monitoring but not evaluative phase of response inhibition as measured by N2 and P3a amplitude, respectively. Unexpectedly, cannabis users with high DI demonstrated stressor-elicited enhancement rather than impairment of conflict-monitoring neural activity, which was related to faster reaction time (RT) and decreased past-month cannabis problems. Enhanced inhibition-related modulation of P3a amplitude was generally associated with increased cannabis problems regardless of acute stress. Results did not provide support for stress-elicited impairment in cognitive control as a mechanism linking high DI and CUD, though some support was found for the relevance of inhibition-related neural activity to CUD. Stress-elicited enhancement of conflict-monitoring neural activity during response inhibition may reflect an adaptive neural response among cannabis users with high DI that protects against CUD in this at-risk group. (PsycINFO Database Record (c) 2018 APA, all rights reserved).