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ABSTRACT Objective Methods Results Discussion To explore dietary‐restraint as a mediator of binge eating and weight‐loss outcomes within a randomized controlled trial comparing cognitive‐behavioral therapy (CBT) and behavioral weight loss (BWL) for binge‐eating disorder (BED) with obesity.Ninety participants were randomly assigned to CBT or BWL and assessed by evaluators blinded to conditions at pretreatment, throughout‐, and post‐treatment (6 months). Three dietary‐restraint measures (Eating Disorder Examination‐Questionnaire [EDE‐Q]‐Restraint, Three‐Factor Flexible‐Restraint and Rigid‐Restraint) were administered at pretreatment and after 2 months of treatment. Regression models examined whether changes at 2‐months in the restraint scales mediated the effects of treatment (CBT versus BWL) on binge eating and weight‐loss outcomes at post‐treatment.CBT and BWL had similar binge‐eating outcomes and similar changes in EDE‐Q‐restraint and flexible‐restraint. BWL had greater 2‐month increases in rigid‐restraint and greater weight‐loss at posttreatment than CBT, with results suggesting 2‐month changes in rigid‐restraint mediated the greater difference (>7 pounds) in weight‐loss. The observed mediation effect of 2.92 suggests 39% of total treatment‐effect on weight‐loss was mediated through 2‐month increases in rigid‐restraint.This secondary analysis within a trial comparing CBT and BWL for BED suggests early‐change in rigid‐restraint has a mediating effect of BWL on weight‐loss. Findings indicate that BWL improves binge eating and challenge views that dietary‐restraint might exacerbate binge eating in BED with obesity. Findings require confirmation using hypothesis‐testing in future trials.Trial Registration: Clinicaltrials.gov: NCT00537758 (“Treatment for Obesity and Binge Eating Disorder”) [ABSTRACT FROM AUTHOR]

Background and Objectives: Childhood trauma (CT) increases addiction vulnerability. We examined CT's impact on delta‐9‐tetrahydrocannabinol (THC) effects. Methods: This is a post‐hoc analysis of a randomized, placebo‐controlled, crossover trial investigating the effects of oral THC (10, 20 mg) among 25 persons receiving methadone for opioid use disorder (OUD). Results: Greater CT was associated with lower aversive effects from higher THC doses (20 mg) (p =.006). Discussion and Conclusions: CT may reduce the subjective aversive effects of THC, potentially leading to greater cannabis use in individuals with OUD. Scientific Significance: These findings offer insights into THC's risks versus benefits in OUD subgroups and emphasize assessing CT in OUD treatment and research. [ABSTRACT FROM AUTHOR]

Purpose: Aging is a major societal concern due to age-related functional losses. Synapses are crucial components of neural circuits, and synaptic density could be a sensitive biomarker to evaluate brain function. [11C]UCB-J is a positron emission tomography (PET) ligand targeting synaptic vesicle glycoprotein 2A (SV2A), which can be used to evaluate brain synaptic density in vivo. Methods: We evaluated age-related changes in gray matter synaptic density, volume, and blood flow using [11C]UCB-J PET and magnetic resonance imaging (MRI) in a wide age range of 80 cognitive normal subjects (21–83 years old). Partial volume correction was applied to the PET data. Results: Significant age-related decreases were found in 13, two, and nine brain regions for volume, synaptic density, and blood flow, respectively. The prefrontal cortex showed the largest volume decline (4.9% reduction per decade: RPD), while the synaptic density loss was largest in the caudate (3.6% RPD) and medial occipital cortex (3.4% RPD). The reductions in caudate are consistent with previous SV2A PET studies and likely reflect that caudate is the site of nerve terminals for multiple major tracts that undergo substantial age-related neurodegeneration. There was a non-significant negative relationship between volume and synaptic density reductions in 16 gray matter regions. Conclusion: MRI and [11]C-UCB-J PET showed age-related decreases of gray matter volume, synaptic density, and blood flow; however, the regional patterns of the reductions in volume and SV2A binding were different. Those patterns suggest that MR-based measures of GM volume may not be directly representative of synaptic density. [ABSTRACT FROM AUTHOR]

Cognitive training for Attention Deficit/Hyperactivity Disorder (ADHD) has shown promising, although mixed results. In post-hoc analyses, we evaluate effects of cognitive training using a novel composite cognition score as the outcome for children attending at least 16 sessions of training, dose-response of training and associations between symptoms and cognitive functioning. Children (age 6–13) with ADHD were randomized to intervention (n = 26) or control (n = 34). For the current analysis, we restricted the intervention group to children, who completed at least 16 sessions of cognitive training (n = 26) and examined a dose response within that group. Cognition improved significantly in the intervention, but not control group. Amount of the completed training sessions correlated significantly with the amount of cognitive improvement. Variations in dose and frequency of training may be an important source of the variance in previous studies. [ABSTRACT FROM AUTHOR]

Previous research reported an age‐related decline in brain norepinephrine transporter (NET) using (S, S)‐[11C]O‐methylreboxetine ([11C]MRB) as a radiotracer. Studies with the same tracer have been mixed in regard to differences related to body mass index (BMI). Here, we investigated potential age‐, BMI‐, and gender‐related differences in brain NET availability using [11C]MRB, the most selective available radiotracer. Forty‐three healthy participants (20 females, 23 males; age range 18–49 years), including 12 individuals with normal/lean weight, 15 with overweight, and 16 with obesity were scanned with [11C]MRB using a positron emission tomography (PET) high‐resolution research tomograph (HRRT). We evaluated binding potential (BPND) in brain regions with high NET availability using multilinear reference tissue model 2 (MRTM2) with the occipital cortex as a reference region. Brain regions were delineated with a defined anatomic template applied to subjects' structural MR scans. We found a negative association between age and NET availability in the locus coeruleus, raphe nucleus, and hypothalamus, with a 17%, 19%, and 14% decrease per decade, respectively, in each region. No gender or BMI relationships with NET availability were observed. Our findings suggest an age‐related decline, but no BMI‐ or gender‐related differences, in NET availability in healthy adults. [ABSTRACT FROM AUTHOR]

Background: Evidence suggests that serotonergic psychedelics (e.g. psilocybin), have rapid-acting and long-lasting antidepressant effects after a single dose. However, the mechanism underlying these effects remain unclear. One proposed mechanism is that these drugs promote neuroplasticity. However, this has not been conclusively demonstrated in humans. Aims: We hypothesized that relative to placebo, psilocybin would: (1) increase electroencephalographic (EEG) correlates of neuroplasticity, (2) reduce depression symptoms, and (3) changes in EEG would correlate with improvements in depression. Methods: In this double-blind, placebo-controlled, within-subject study, individuals with major depressive disorder (MDD; n = 19) were administered placebo followed by psilocybin (0.3 mg/kg) in a fixed order (placebo, followed by psilocybin 4 weeks later). EEG indices of neuroplasticity (tetanus-induced long-term potentiation) as assessed via auditory evoked theta (4–8 Hz) power and measures of depression (GRID Hamilton Rating Scale for Depression-17 (GRID-HAM-D-17)) were measured at several time-points after placebo and psilocybin (24 h and 2 weeks after each session). Results: EEG theta power doubled in amplitude 2 weeks after a single psychedelic dose of psilocybin but not after placebo. Further, improvements in depression symptoms 2 weeks after psilocybin were correlated with increases in theta power. Conclusions: The increased theta power observed represents evidence of sustained changes in the brain following psilocybin. Given the correlation with enhancement in depressive symptoms, changes in theta may represent an EEG biomarker of the sustained effects of psilocybin, and may shed light on potential mechanisms of psilocybin's antidepressant effect. Taken together, these results complement the emerging notion that psilocybin, and perhaps other psychedelics, can produce long-term alterations in neuroplasticity. [ABSTRACT FROM AUTHOR]

Introduction Count outcomes in tobacco research are often analyzed with the Poisson distribution. However, they often exhibit features such as overdispersion (variance larger than expected) and zero inflation (extra zeros) that violate model assumptions. Furthermore, longitudinal studies have repeated measures that generate correlated counts. Failure to account for overdispersion, zero inflation, and correlation can yield incorrect statistical inferences. Thus, it is important to familiarize researchers with proper models for such data. Aims and Methods Poisson and Negative Binomial models with correlated random effects with and without zero inflation are presented. The illustrative data comes from a study comparing a mindfulness training app (Craving to Quit [C2Q], n = 60) with a control app (experience sampling-only app, n = 66) on smoking frequency at 1, 3, and 6 months. Predictors include app, time, the app-by-time interaction, and baseline smoking. Each model is evaluated in terms of accounting for zero inflation, overdispersion, and correlation in the data. Emphasis is placed on evaluating model fit, subject-specific interpretation of effects, and choosing an appropriate model. Results The hurdle Poisson model provided the best fit to the data. Smoking abstinence rates were 33%, 32%, and 28% at 1, 3, and 6 months, respectively, with variance larger than expected by a factor >7 at each follow-up. Individuals on C2Q were less likely to achieve abstinence across time but likely to smoke fewer cigarettes if smoking. Conclusions The models presented are specifically suited for analyzing correlated count outcomes and account for zero inflation and overdispersion. We provide guidance to researchers on the use of these models to better inform nicotine and tobacco research. Implications In tobacco research, count outcomes are often measured repeatedly on the same subject and thus correlated. Such outcomes often have many zeros and exhibit large variances relative to the mean. Analyzing such data require models specifically suited for correlated counts. The presented models and guidelines could improve the rigor of the analysis of correlated count data and thus increase the impact of studies in nicotine and tobacco research using such outcomes. [ABSTRACT FROM AUTHOR]