Individuals with attentional and emotional dysfunctions are most at risk for smoking initiation and subsequent nicotine addiction. This article presents converging findings from human behavioral research, brain imaging, and basic neuroscience on smoking as self-medication for attentional and emotional dysfunctions. Nicotine and other tobacco constituents have significant effects on neural circuitry underlying the regulation of attention and affect. Age, sex, early environment, and exposure to other drugs have been identified as important factors that moderate both the effects of nicotine on brain circuitry and behavior and the risk for smoking initiation. Findings also suggest that the effects of smoking differ depending on whether smoking is used to regulate attention or affect. Individual differences in the reinforcement processes underlying tobacco use have implications for the development of tailored smoking cessation programs and prevention strategies that include early treatment of attentional and emotional dysfunctions.

CONTEXT: Research reveals racial, ethnic, and socioeconomic disparities in autism diagnosis; there is limited information on potential disparities related to other dimensions of services.OBJECTIVE: We reviewed evidence related to disparities in service use, intervention effectiveness, and quality of care provided to children with autism by race, ethnicity, and/or socioeconomic status.

BackgroundThis is one of the first studies to examine the structural brain anatomy and connectivity associated with an ADHD diagnosis and child as well as adult ADHD symptoms in young adults. It was hypothesized that an adult ADHD diagnosis and in particular childhood symptoms, are associated with widespread changes in the brain macro- and microstructure, which can be used to develop a morphometric biomarker for ADHD.MethodsVoxel-wise linear regression models were used to examine structural and diffusion-weighted MRI data in 72 participants (31 young adults with ADHD and 41 controls without ADHD) in relation to diagnosis and the number of self-reported child and adult symptoms.ResultsFindings revealed significant associations between ADHD diagnosis and widespread changes to the maturation of white matter fiber bundles and gray matter density in the brain, such as structural shape changes (incomplete maturation) of the middle and superior temporal gyrus, and fronto-basal portions of both frontal lobes. ADHD symptoms in childhood showed the strongest association with brain macro- and microstructural abnormalities. At the brain circuitry level, the superior longitudinal fasciculus (SLF) and cortico-limbic areas are dysfunctional in individuals with ADHD. The morphometric findings predicted an ADHD diagnosis correctly up to 83% of all cases.ConclusionAn adult ADHD diagnosis and in particular childhood symptoms are associated with widespread micro- and macrostructural changes. The SLF and cortico-limbic findings suggest complex audio-visual, motivational, and emotional dysfunctions associated with ADHD in young adults. The sensitivity of the morphometric findings in predicting an ADHD diagnosis was sufficient, which indicates that MRI-based assessments are a promising strategy for the development of a biomarker.

Whereas the smoking prevalence rates in the general population are declining, rates among people diagnosed with attention-deficit/hyperactivity disorder (ADHD) continue to be elevated. Previous research has shown that nicotine may improve attention and mood, suggesting that nicotine may help ameliorate the attentional and emotional problems associated with ADHD. The present study examined the effects of nicotine with and without stimulant medication on ADHD symptoms, moods, and arousal in the everyday lives of smokers with ADHD. A total of 10 smokers with ADHD who were being treated with stimulant medication were asked to abstain from smoking while participating in the study. Participants underwent four conditions in randomized order: (a) Nicotine patch+stimulant medication, (b) nicotine patch only, (c) placebo patch+stimulant medication, and (d) placebo patch only. Each condition continued for 2 days, during which self-reports of ADHD symptoms and moods were obtained using electronic diaries. Lightweight ambulatory monitors recorded cardiovascular activity at each diary entry. Smoking abstinence was verified by expired carbon monoxide and salivary cotinine analysis. Results showed that nicotine patches and stimulant medication alone and in combination reduced difficulty concentrating and core ADHD symptoms compared with placebo patch only. Borderline improvement in impatience and self-control was seen with nicotine patch administration primarily on day 1. Nicotine patches also tended to elevate systolic and diastolic blood pressure compared with placebo patch during day 2. The findings suggest that smokers with ADHD experience nicotine-related reductions in ADHD symptoms during their everyday lives.

The aim of the study was to test the self-medication hypothesis by examining the effects of nicotine in the everyday lives of smokers and nonsmokers with attention-deficit/hyperactivity disorder (ADHD). Fifty-two adults with ADHD (25 abstinent smokers and 27 nonsmokers) participated in a double-blind placebo controlled study with one nicotine patch condition and one placebo patch condition in counterbalanced order. Each condition continued for two consecutive days in which patches were administered each morning. The effects of nicotine on ADHD symptoms, moods, and side effects were assessed with electronic diaries. Cardiovascular activity was recorded with ambulatory blood pressure monitors and physical activity was monitored with actigraphs. Nicotine reduced reports of ADHD symptoms by 8% and negative moods by 9%, independent of smoking status. In addition, nicotine increased cardiovascular activity during the first 3 to 6 hours after nicotine patch administration. The results support the self-medication hypothesis for nicotine in adults with ADHD and suggest that smoking cessation and prevention efforts for individuals with ADHD will need to address both the symptom reducing and mood enhancing effects of nicotine.

The results show that sleep problems are associated with hyperactive and impulsive symptoms in nonmedicated adults with ADHD. These findings provide information on the nature of sleep problems without the confounding effects of medication associated with ADHD. Treatment of sleep problems, especially in those with hyperactive-impulsive symptoms, may help ameliorate ADHD symptomatology.

ADHD is the most common neurobehavioral disorder of childhood, presenting with pervasive and impairing symptoms of inattention, hyperactivity, impulsivity, or a combination. The leading hypothesis of the underlying physiology of this disorder of inattention and/or hyperactivity-impulsivity is based on catecholamine dysfunction. Pharmacotherapy research indicates that psychostimulants, which are catecholamine agonists, show the greatest efficacy for treating the core symptoms of ADHD. Exercise affects the same dopaminergic and noradrenergic systems that stimulant medications target and is a stressor, which elicits measurable physiological changes. The magnitude of these peripheral alterations is posited as a potential biomarker of ADHD. The hypothesis that exercise training alters the underlying physiology present in ADHD and other medical conditions as well as conceptual issues behind its potential clinical utility is reviewed.

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