Obesity and dissociable forms of impulsivity in young adults.

OBJECTIVE: Obesity is one of the leading causes of preventable morbidity and mortality, and young people are increasingly affected. The aim of this study was to examine relationships between obesity and dissociable forms of impulsivity in young adults. METHODS: A group of young adults (511) was recruited from city areas in the United States using media advertisements. These young adults were administered careful and extensive clinical and neurocognitive assessment in order to quantify different aspects of impulsivity (behavioral/phenomenological-, cognitive-, and personality-related measures). Associations between obesity and impulsivity were explored using multivariate analysis of variance and discriminant function analysis. RESULTS: 10.8% of the sample was obese, and 21.5% was overweight. Compared to controls, subjects with obesity showed significantly elevated rates of maladaptive gambling behaviors, monetary amounts lost to gambling, nicotine consumption, impulsive action (prolonged stop-signal reaction times in the Stop-Signal Test), and impulsive decision-making (reduced modulation of behavior as a function of risk in the Cambridge Gamble Test). Even accounting for potential confounding variables, obesity was significantly predicted by female gender, older age, more maladaptive gambling behaviors, and worse inhibitory control (stop-signal reaction times). CONCLUSION: Obesity is associated with several dissociable forms of impulsivity in young people, especially gambling and impulse dyscontrol. Family doctors should screen for gambling problems in obese young adults. Successful treatment of nicotine dependence in young obese people is likely to require intensive weight management support. Neuropsychological deficits relating to impulsivity occur in obese people in early adulthood, and may represent vulnerability markers rather than being due to chronic untoward metabolic effects on brain function.This research was supported by a Center for Excellence in Gambling Research grant to Dr. Grant from the National Center for Responsible Gaming (USA) and by the Academy of Medical Sciences (UK; grant to Dr. Chamberlain).This is the author accepted manuscript. The final version is available from CUP at http://dx.doi.org/10.1017/S109285291400062

Impaired response inhibition and excess cortical thickness as candidate endophenotypes for trichotillomania.

This is the author accepted manuscript. the final version is available via Elsevier at http://www.sciencedirect.com/science/article/pii/S0022395614002465.Trichotillomania is characterized by repetitive pulling out of one's own hair. Impaired response inhibition has been identified in patients with trichotillomania, along with gray matter density changes in distributed neural regions including frontal cortex. The objective of this study was to evaluate impaired response inhibition and abnormal cortical morphology as candidate endophenotypes for the disorder. Subjects with trichotillomania (N = 12), unaffected first-degree relatives of these patients (N = 10), and healthy controls (N = 14), completed the Stop Signal Task (SST), a measure of response inhibition, and structural magnetic resonance imaging scans. Group differences in SST performance and cortical thickness were explored using permutation testing. Groups differed significantly in response inhibition, with patients demonstrating impaired performance versus controls, and relatives occupying an intermediate position. Permutation cluster analysis revealed significant excesses of cortical thickness in patients and their relatives compared to controls, in right inferior/middle frontal gyri (Brodmann Area, BA 47 & 11), right lingual gyrus (BA 18), left superior temporal cortex (BA 21), and left precuneus (BA 7). No significant differences emerged between groups for striatum or cerebellar volumes. Impaired response inhibition and an excess of cortical thickness in neural regions germane to inhibitory control, and action monitoring, represent vulnerability markers for trichotillomania. Future work should explore genetic and environmental associations with these biological markers.This research was supported by a grant from the Trichotillomania Learning Center, USA, to Mr. Odlaug; and by a grant from the Academy of Medical Sciences, UK, to Dr. Chamberlain. Neither of these entities had any further role in study design; in the collection, analysis and interpretation of data; in the writing of the report; or in the decision to submit the paper for publication

Impulse control disorders in non-treatment seeking hair pullers

Background and aims: Hair pulling is a common body focused repetitive behavior. The purpose of this paper is to examine the prevalence of impulse control disorders (as defined in DSM-IV-TR) in a non-treatment seeking sample of hair pullers. Methods: 1,717 college students with (n = 44) and without (n = 1673) hair pulling completed a mental health survey. The college students were sent an online survey assessing hair pulling behavior and other impulse control disorders using the Minnesota Impulsive Disorders Interview. Results: Students with hair pulling were significantly more likely to have a co-occurring impulse control disorder (20.5% vs. 8.9%, p = 0.009, OR = 2.71, CI = 1.28–5.75) and were significantly more likely to meet criteria for compulsive buying, compulsive sexual behavior and intermittent explosive disorder than students without hair pulling. Differences seemed to be moderated by the male gender among students with hair pulling. Discussion and conclusions: Hair pulling is often comorbid with another impulse control disorder, which suggests that elements of impulsivity may be important in our understanding of hair pulling. Furthermore, gender may moderate impulse control comorbidity in hair pulling disorder

Sleepiness and cognition in young adults who gamble and use alcohol

Abstract Background and aims Past research suggests that sleep problems are associated with increased risky decision-making. Similarly, gambling disorder and alcohol use disorder are also associated with increased risky decision-making. Individuals with gambling disorder or alcohol use disorder have also reported higher rates of sleep problems compared to normal healthy controls. As such, we sought to examine whether sleep problems play a role in the development of alcohol use disorder or gambling disorder. Methods One hundred and forty-one individuals who gamble and use alcohol, yet do not meet criteria for gambling disorder or alcohol use disorder, were assessed to determine the correlation between sleepiness, amount of sleep obtained, decision-making, and alcohol or gambling behaviors. Results Our results suggest that inconsistent sleep patterns may be associated with increased frequency of alcohol use and gambling. We did not, however, find a significant correlation between sleep factors and decision-making. Discussion Further research is needed to examine the specific relationship between sleep patterns and alcohol use and gambling frequency. Overall these data suggest that sleepiness or sleep and risky decision-making is not a significant factor in gambling and alcohol use behaviors in individuals not meeting criteria for alcohol use disorder or gambling disorder

System for MR image-guided prostate interventions: canine study

Cataloged from PDF version of article.The purpose of this study was to demonstrate the use of a transrectal system that enables precise magnetic resonance (MR) image guidance and monitoring of prostate interventions. The system used a closed-bore 1.5-T MR imaging unit and enables one to take advantage of the higher signal-to-noise ratio achieved with traditional magnet designs, which is crucial for accurate targeting and monitoring of prostate interventions. In the first of the four canine studies, reliable needle placement, with all needles placed within 2 mm of the desired target site, was achieved. In two other studies, MR imaging was used to monitor distribution of injected contrast agent solution (gadopentetate dimeglumine mixed with trypan blue dye) in and around the prostate, thereby confirming that solution had been delivered to the desired tissue and also detecting faulty injections. In the final study, accurate placement and MR imaging of brachytherapy seeds in the prostate were demonstrated. The described system provides a flexible platform for a variety of minimally invasive MR image-guided therapeutic and diagnostic prostate interventions

Prevalence and correlates of being overweight or obese in college.

Recent statistics indicate that over one-third of college students are currently overweight or obese, however, the impact of weight in this population from academic and psychiatric perspectives is not fully understood. This study sought to examine the prevalence of overweight and obesity in college students and its association with stress, mental health disorders and academic achievement. A total of 1765 students completed the College Student Computer User Survey (CSCUS) online at a large Midwestern United States University. Responders were classified by weight as normal, overweight or obese based on body mass index. Data were stratified by sex, with cross-tabulation and t-tests, one-way analysis of variance, and logistic regression for analysis. A total of 492 (27.9%) students were overweight (20.2%; range 25.01-29.98) or obese (7.7%; range 30.04-71.26). Overweight and obesity were associated with significantly lower overall academic achievement, more depressive symptoms, and using diet pills for weight loss. Obese males had significantly higher rates of lifetime trichotillomania while overweight and obese females reported higher rates of panic disorder. Higher educational institutions should be aware of the significant burden associated with overweight and obesity in students, and of the differing demographic and clinical associations between overweight or obesity in men and women.This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.psychres.2015.01.02

White matter tract integrity in treatment-resistant gambling disorder.

BACKGROUND: Gambling disorder is a relatively common psychiatric disorder recently re-classified within the DSM-5 under the category of 'substance-related and addictive disorders'. AIMS: To compare white matter integrity in patients with gambling disorder with healthy controls; to explore relationships between white matter integrity and disease severity in gambling disorder. METHOD: In total, 16 participants with treatment-resistant gambling disorder and 15 healthy controls underwent magnetic resonance imaging (MRI). White matter integrity was analysed using tract-based spatial statistics. RESULTS: Gambling disorder was associated with reduced fractional anisotropy in the corpus callosum and superior longitudinal fasciculus. Fractional anisotropy in distributed white matter tracts elsewhere correlated positively with disease severity. CONCLUSIONS: Reduced corpus callosum fractional anisotropy is suggestive of disorganised/damaged tracts in patients with gambling disorder, and this may represent a trait/vulnerability marker for the disorder. Future research should explore these measures in a larger sample, ideally incorporating a range of imaging markers (for example functional MRI) and enrolling unaffected first-degree relatives of patients.This research was supported by a grant from the National Center for Responsible Gaming to Dr. Grant, and by a grant from the Academy of Medical Sciences to Dr. Chamberlain (UK). Dr. Grant has received research grants from NIMH, National Center for Responsible Gaming, and Forest and Roche Pharmaceuticals Dr. Grant receives yearly compensation from Springer Publishing for acting as Editor-in-Chief of the Journal of Gambling Studies and has received royalties from Oxford University Press, American Psychiatric Publishing, Inc., Norton Press, and McGraw Hill. Dr. Chamberlain consults for Cambridge Cognition. Mr. Odlaug has received a research grant from the Trichotillomania Learning Center, consults for H. Lundbeck A/S, and has received royalties from Oxford University Press. Mr. Leppink and Ms. Derbyshire report no conflicts of interest.This is the author accepted manuscript. The final version is available from the Royal College of Psychiatrists via http://dx.doi.org/10.1192/bjp.bp.115.16550

Near-Field Pressure Signature Splicing for Low-Fidelity Design Space Exploration of Supersonic Aircraft

As interest in supersonic overland flight intensifies, new ways to meet government restrictions on sonic boom loudness must be implemented. Low-fidelity aerodynamic tools, such as PANAIR, can estimate the near-field pressure signature that ultimately determines the loudness of the sonic boom at the ground. These tools can greatly benefit the exploration of large design spaces due to their computational efficiency. One of the limitations of low-fidelity tools is the accuracy of the solution produced, which is dependent on the fundamental physical assumptions made in the development of the governing equations. If flow patterns are produced that severely violate these fundamental assumptions, the validity of the near-field pressure signature is compromised. A method is proposed that splices together near-field pressure signatures from a low-fidelity and a higher-fidelity tool by cutting each pressure signature at a critical point and then blending the low-fidelity signature into the higher-fidelity signature. By splicing the signatures together, sections of the low-fidelity signature that represent fundamental violations of the governing equation are removed. This method allows for the exploration of the design space corresponding to areas on the geometry that produce accurate results in a low-fidelity signature. The method is tested on the JAXA Wing Body geometry from the Second AIAA Sonic Boom Prediction Workshop and shows that perturbations to this geometry can produce loudness results that match the high-fidelity results to within 0.4 PLdB