Familial effects account for association between chronic pain and past month smoking.

BACKGROUND: Smoking is associated with chronic pain, but it is not established whether smoking causes pain or if the link is due to familial effects. One proposed mechanism is that smoking strengthens maladaptive cortico-striatal connectivity, which contributes to pain chronification. We leveraged a twin design to assess direct effects of smoking on pain controlling for familial confounds, and whether cortico-striatal connectivity mediates this association. METHODS: In a population-based sample of 692 twins (age = 28.83 years), we assessed past-month smoking frequency (n = 132 used in the past month), presence and severity of a current pain episode (n = 179 yes), and resting-state functional connectivity of the nucleus accumbens and medial prefrontal cortex (NAc-mPFC). RESULTS: Smoking was significantly associated with pain, but the association was not significantly mediated by NAc-mPFC connectivity. In a co-twin control model, smoking predicted which families had more pain but could not distinguish pain between family members. Pain risk was 43% due to additive genetic (A) and 57% due to non-shared environmental (E) influences. Past-month smoking frequency was 71% genetic and 29% non-shared environmental. Smoking and pain significantly correlated phenotypically (r = 0.21, p = 0.001) and genetically (rg = 0.51, p < 0.001), but not environmentally (re = -0.18, p = 0.339). CONCLUSIONS: Pain and smoking are associated; however, the association appears to reflect shared familial risk factors, such as genetic risk, rather than being causal in nature. The connectivity strength of the reward pathway was not related to concurrent pain and smoking in this sample. SIGNIFICANCE: Smoking does not appear to directly cause chronic pain; rather, there may be shared biopsychosocial risk factors, including genetic influences, that explain their association. These findings can be integrated into future research to identify shared biological pathways of both chronic pain and smoking behaviours as a way to conceptualize pain chronification.

Substance use patterns in 9-10 year olds: Baseline findings from the adolescent brain cognitive development (ABCD) study.

BACKGROUND: The Adolescent Brain Cognitive Development ™ Study (ABCD Study®) is an open-science, multi-site, prospective, longitudinal study following over 11,800 9- and 10-year-old youth into early adulthood. The ABCD Study aims to prospectively examine the impact of substance use (SU) on neurocognitive and health outcomes. Although SU initiation typically occurs during teen years, relatively little is known about patterns of SU in children younger than 12. METHODS: This study aims to report the detailed ABCD Study® SU patterns at baseline (n = 11,875) in order to inform the greater scientific community about cohort's early SU. Along with a detailed description of SU, we ran mixed effects regression models to examine the association between early caffeine and alcohol sipping with demographic factors, externalizing symptoms and parental history of alcohol and substance use disorders (AUD/SUD). PRIMARY RESULTS: At baseline, the majority of youth had used caffeine (67.6 %) and 22.5 % reported sipping alcohol (22.5 %). There was little to no reported use of other drug categories (0.2 % full alcohol drink, 0.7 % used nicotine, <0.1 % used any other drug of abuse). Analyses revealed that total caffeine use and early alcohol sipping were associated with demographic variables (p's<.05), externalizing symptoms (caffeine p = 0002; sipping p = .0003), and parental history of AUD (sipping p = .03). CONCLUSIONS: ABCD Study participants aged 9-10 years old reported caffeine use and alcohol sipping experimentation, but very rare other SU. Variables linked with early childhood alcohol sipping and caffeine use should be examined as contributing factors in future longitudinal analyses examining escalating trajectories of SU in the ABCD Study cohort.

The unity and diversity of executive functions and their contributions to complex "Frontal Lobe" tasks: a latent variable analysis.

This individual differences study examined the separability of three often postulated executive functions-mental set shifting ("Shifting"), information updating and monitoring ("Updating"), and inhibition of prepotent responses ("Inhibition")-and their roles in complex "frontal lobe" or "executive" tasks. One hundred thirty-seven college students performed a set of relatively simple experimental tasks that are considered to predominantly tap each target executive function as well as a set of frequently used executive tasks: the Wisconsin Card Sorting Test (WCST), Tower of Hanoi (TOH), random number generation (RNG), operation span, and dual tasking. Confirmatory factor analysis indicated that the three target executive functions are moderately correlated with one another, but are clearly separable. Moreover, structural equation modeling suggested that the three functions contribute differentially to performance on complex executive tasks. Specifically, WCST performance was related most strongly to Shifting, TOH to Inhibition, RNG to Inhibition and Updating, and operation span to Updating. Dual task performance was not related to any of the three target functions. These results suggest that it is important to recognize both the unity and diversity of executive functions and that latent variable analysis is a useful approach to studying the organization and roles of executive functions.

Assessment of executive functions in clinical settings: problems and recommendations.

In this article we provide a tutorial review of various theoretical issues that surround executive function research from the perspective of cognitive psychology, focusing on issues that have important implications for clinical assessment of executive functioning. We first discuss theoretical and clinical reasons for the importance of understanding executive functions and then point out some serious problems with the common practice of relying exclusively on complex neuropsychological tests, such as the Wisconsin Card Sorting Test and the Tower of Hanoi, as general measures of executive functioning. We then briefly present a recent individual differences study of executive functions conducted in our laboratory that attempted to overcome certain limitations associated with the more typical approach. On the basis of the theoretical issues discussed and the results from our study, we offer some concrete suggestions and recommendations for the measurement and assessment of executive functions in clinical settings.

Differential roles for visuospatial and verbal working memory in situation model construction.

Two experiments investigated the processing of the spatial and causal dimensions of situation models. In Experiment 1, participants read texts varying in spatial and causal demands while responding to on-line spatial and causal probes. Experiment 2 used the same design, but used texts that more tightly integrated spatial and causal information. In both experiments, spatially oriented dependent measures were generally influenced by spatial, but not causal, demands, whereas causally oriented measures were influenced by causal, but not spatial, demands. In addition, spatially oriented dependent measures were generally correlated with a measure of spatial working memory capacity, whereas causally oriented measures were correlated with a measure of verbal working memory capacity. These results indicate that spatial and causal dimensions of situation models are maintained and elaborated independently in different working memory subsystems.