Light Cannabis Use and the Adolescent Brain: An 8-years Longitudinal Assessment of Mental Health, Cognition, and Reward Processing

RATIONALE

For decades, cannabis has been the most widely used illicit substance in the world, particularly among youth. Research suggests that mental health problems associated with cannabis use may result from its effect on reward brain circuit, emotional processes, and cognition. However, findings are mostly derived from correlational studies and inconsistent, particularly in adolescents.

OBJECTIVES AND METHODS

Using data from the IMAGEN study, participants (non-users, persistent users, abstinent users) were classified according to their cannabis use at 19 and 22 years-old. All participants were cannabis-naïve at baseline (14 years-old). Psychopathological symptoms, cognitive performance, and brain activity while performing a Monetary Incentive Delay task were used as predictors of substance use and to analyze group differences over time.

RESULTS

Higher scores on conduct problems and lower on peer problems at 14 years-old (n = 318) predicted a greater likelihood of transitioning to cannabis use within 5 years. At 19 years of age, individuals who consistently engaged in low-frequency (i.e., light) cannabis use (n = 57) exhibited greater conduct problems and hyperactivity/inattention symptoms compared to non-users (n = 52) but did not differ in emotional symptoms, cognitive functioning, or brain activity during the MID task. At 22 years, those who used cannabis at both 19 and 22 years-old n = 17), but not individuals that had been abstinent for ≥ 1 month (n = 19), reported higher conduct problems than non-users (n = 17).

CONCLUSIONS

Impairments in reward-related brain activity and cognitive functioning do not appear to precede or succeed cannabis use (i.e., weekly, or monthly use). Cannabis-naïve adolescents with conduct problems and more socially engaged with their peers may be at a greater risk for lighter yet persistent cannabis use in the future.

Autistic traits and event-related potentials in the general population: A scoping review and meta-analysis

BACKGROUND

Differences in short and long-latency Event-Related Potentials (ERPs) can help us infer abnormalities in brain processing, considering early and later stages of stimuli processing across tasks and conditions. In autism research, the adult population remains largely understudied compared to samples at early stages of development. In this context, this scoping review briefly summarises what has been described in community and subclinical adult samples of autism.

METHOD

The current scoping review and meta-analysis includes 50 records (N = 1652) and comprehensively explores short and long-latency ERP amplitudes and their relationship with autistic traits in adult community samples.

RESULTS

This meta-analysis identified, with small to medium effect sizes, distinctive patterns in late ERP amplitudes, indicating enhanced responses to visual stimuli and the opposite patterns to auditory tasks in the included sample. Additionally, a pattern of higher amplitudes was also found for the component P3b in autistic traits.

DISCUSSION

Differential effects in visual and auditory domains are explored in light of the predictive processing framework for Autism. It remains possible that different brain mechanisms operate to explain symptoms related with different sensory modalities. P3b is discussed as a possible component of interest in future studies as it revealed a more robust effect for differentiating severity in the expression of autistic traits in adulthood.

Modeling relations between event-related potential factors and broader versus narrower dimensions of externalizing psychopathology

The organization of the Hierarchical Taxonomy of Psychopathology (HiTOP) model provides unique opportunities to evaluate whether neural risk measures operate as indicators of broader latent liabilities (e.g., externalizing proneness) or narrower expressions (e.g., antisociality and alcohol abuse). Following this approach, the current study recruited a sample of 182 participants (54% female) who completed measures of externalizing psychopathology (also internalizing) and associated traits. Participants also completed three tasks (Flanker-No Threat, Flanker-Threat, and Go/No-Go tasks) with event-related potential (ERP) measurement. Three variants of two research domain criteria (RDoC)-based neurophysiological indicators-P3 and error-related negativity (ERN)-were extracted from these tasks and used to model two latent ERP factors. Scores on these two ERP factors independently predicted externalizing factor scores when accounting for their covariance with sex-suggesting distinct neural processes contributing to the broad externalizing factor. No predictive relation with the broad internalizing factor was found for either ERP factor. Analyses at the finer-grained level revealed no unique predictive relations of either ERP factor with any specific externalizing symptom variable when accounting for the broad externalizing factor, indicating that ERN and P3 index general liability for problems in this spectrum. Overall, this study provides new insights about neural processes in externalizing psychopathology at broader and narrower levels of the HiTOP hierarchy. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Delay discounting in aging: The influence of cognitive and psychological variables

Delay discounting (or temporal discounting) refers to the decrease of the subjective value of a reward as the time interval for receiving that reward increases. A recent meta-analysis showed that delay discounting appears to be similar across the lifespan as younger, middle-aged, and older adults prefer sooner rewards, despite smaller, over later rewards, even if larger. However further investigation is needed to understand the potential role of individual factors in delay discounting across the lifespan. The present study aimed to contribute to this debate, by investigating the influence of sociodemographic, neurocognitive, and psychological variables on delay discounting. For this purpose, 88 participants (30 younger, 30 middle-aged, and 28 older adults) aged between 19 and 73 years old completed the Monetary Choice Questionnaire (MCQ), a comprehensive battery of neurocognitive tests, and self-report measures of psychopathology. Results revealed no group differences in the rate of discounting. A well-established effect of the amount of the delayed reward was replicated, showing that medium rewards were less discounted than smaller rewards, and larger rewards had lower discounting rates than smaller and medium rewards-the magnitude effect. Regarding the influence of neurocognitive and psychological factors on delay discounting, better working memory, as assessed by the Corsi block-tapping task, significantly predicted larger magnitude effects. The findings of the current work are consistent with the results of previous studies, suggesting that temporal discounting is a stable function across the adult life span. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Economic decision-making in the continuum between healthy aging and Alzheimer's Disease: A systematic review of 20 years of research

The effect of pathological aging on economic decision-making is a topic of major relevance as impairments in this domain place older adults at increased risk for financial abuse. This review aims to characterize decision-making across the continuum that goes from healthy aging to Alzheimer's Dementia. We included 42 studies comparing patients with Mild Cognitive Impairment (MCI) and healthy older adults, patients with Alzheimer's Disease (AD) and healthy older adults, and patients with MCI and patients with AD. Substantial evidence emerged suggesting that both MCI as AD affect economic decision-making. However, a non-negligible number of behavioural tasks failed to find significant differences between patients and controls, and no differences were reported between patients with MCI and AD. On the contrary, measures of financial capacity reached more robust findings, showing that healthy older adults had better performance than patients, while MCI patients showed better performance than AD patients. This review presents the main conclusions that may be drawn from significant findings, as well as the hypotheses and recommendations for future research.

A dimensional approach to the neuronal correlates of anxiety, depression, and perfectionism: A transdiagnostic dissociation of error-related brain activity

Transdiagnostic approaches such as the Research Domain Criteria (RDoC) highlight the importance of addressing psychopathological constructs dimensionally, since comorbidity and heterogeneity represent prevalent issues in the available categorical diagnosis. The current study analyses distinct internalizing dimensions of depression and anxiety, and the transdiagnostic feature of perfectionism on the modulation of error-related brain activity (i.e., ERN). A sample of 125 participants completed self-reported measures of anxiety, depression, and perfectionism, and performed two versions of the Flanker Task (performance monitoring and sustained-threat) during an EEG recording. In the broad internalizing dimensions, anxiety predicted increased ERN amplitudes when controlling for the shared variance with depression and perfectionism. The narrower dimensions of anxiety and depression revealed a dissociative effect: cognitive anxiety explained blunted ERN amplitudes, while the physiological signs of anxiety and depression predicted increased amplitudes. For perfectionism, no significant results were found. Exploratory analyses further revealed that the Error Positivity component (Pe) was reduced in anxiety and physiological depression. We conclude that anxiety features emerge as the main explanation for the altered patterns of error monitoring in a transdiagnostic sample. Since anxiety is expected to co-occur with other disorders, the current findings suggest that altered patterns of error monitoring will be a transdiagnostic feature of various internalizing and anxiety-related disorders.

Abnormal Habituation of the Auditory Event-Related Potential P2 Component in Patients With Schizophrenia

Auditory event-related potentials (ERP) may serve as diagnostic tools for schizophrenia and inform on the susceptibility for this condition. Particularly, the examination of N1 and P2 components of the auditory ERP may shed light on the impairments of information processing streams in schizophrenia. However, the habituation properties (i.e., decreasing amplitude with the repeated presentation of an auditory stimulus) of these components remain poorly studied compared to other auditory ERPs. Therefore, the current study used a roving paradigm to assess the modulation and habituation of N1 and P2 to simple (pure tones) and complex sounds (human voices and bird songs) in 26 first-episode patients with schizophrenia and 27 healthy participants. To explore the habituation properties of these ERPs, we measured the decrease in amplitude over a train of seven repetitions of the same stimulus (either bird songs or human voices). We observed that, for human voices, N1 and P2 amplitudes decreased linearly from stimulus 1-7, in both groups. Regarding bird songs, only the P2 component showed a decreased amplitude with stimulus presentation, exclusively in the control group. This suggests that patients did not show a fading of neural responses to repeated bird songs, reflecting abnormal habituation to this stimulus. This could reflect the inability to inhibit irrelevant or redundant information at later stages of auditory processing. In turn schizophrenia patients appear to have a preserved auditory processing of human voices.

Adenocarcinoma in situ of the uterine cervix: clinicopathological study of nine cases with detection of human papillomavirus DNA by in situ hybridization and polymerase chain reaction

The clinicopathological features of nine patients with adenocarcinoma in situ (AIS) of the uterine cervix, one of them with microinvasion, were studied. In situ hybridization (ISH) with biotinylated probes to human papillomavirus (HPV) types 6/11, 16/18, and 31/35/51 was performed in eight tumors. The presence of HPV types 16 and 18 was also investigated by the polymerase chain reaction (PCR) in seven. Four tumors were of the endocervical type, two were endometrioid, and three were mixed (endocervical-intestinal). Coexisting cervical intraepithelial squamous neoplasia (CIN) was found in eight tumors. Only one of the eight tumors studied by ISH was positive for HPV 16/18 in the dysplastic squamous epithelium, but none of them showed positivity in the adenocarcinomatous areas. In contrast, four of seven AIS studied by PCR were positive: three for HPV 16 and one (the microinvasive adenocarcinoma) for HPV 18. The results confirm the frequent association of AIS with CIN and HPV.