910 resultados para Attention Deficit Hyperactivity Disorder


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This paper tests for the market environment within which US fiscal policyoperates, that is we test for the incompleteness of the US government bondmarket. We document the stochastic properties of US debt and deficits andthen consider the ability of competing optimal tax models to account forthis behaviour. We show that when a government pursues an optimal taxpolicy and issues a full set of contingent claims, the value of debthas the same or less persistence than other variables in the economyand declines in response to higher deficit shocks. By contrast, ifgovernments only issue one-period risk free bonds (incomplete markets),debt shows more persistence than other variables and it increases inresponse to expenditure shocks. Maintaining the hypothesis of Ramseybehavior, US data conflicts.

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Background: Previous magnetic resonance imaging (MRI) studies in young patients with bipolar disorder indicated the presence of grey matter concentration changes as well as microstructural alterations in white matter in various neocortical areas and the corpus callosum. Whether these structural changes are also present in elderly patients with bipolar disorder with long-lasting clinical evolution remains unclear. Methods: We performed a prospective MRI study of consecutive elderly, euthymic patients with bipolar disorder and healthy, elderly controls. We conducted a voxel-based morphometry (VBM) analysis and a tract-based spatial statistics (TBSS) analysis to assess fractional anisotropy and longitudinal, radial and mean diffusivity derived by diffusion tensor imaging (DTI). Results: We included 19 patients with bipolar disorder and 47 controls in our study. Fractional anisotropy was the most sensitive DTI marker and decreased significantly in the ventral part of the corpus callosum in patients with bipolar disorder. Longitudinal, radial and mean diffusivity showed no significant between-group differences. Grey matter concentration was reduced in patients with bipolar disorder in the right anterior insula, head of the caudate nucleus, nucleus accumbens, ventral putamen and frontal orbital cortex. Conversely, there was no grey matter concentration or fractional anisotropy increase in any brain region in patients with bipolar disorder compared with controls. Limitations: The major limitation of our study is the small number of patients with bipolar disorder. Conclusion: Our data document the concomitant presence of grey matter concentration decreases in the anterior limbic areas and the reduced fibre tract coherence in the corpus callosum of elderly patients with long-lasting bipolar disorder.

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Recent studies have reported specific executive and attentional deficits in preterm children. However, the majority of this research has used multidetermined tasks to assess these abilities, and the interpretation of the results lacks an explicit theoretical backdrop to better understand the origin of the difficulties observed. In the present study, we used the Child Attention Network Task (Child ANT; Rueda et al. 2004) to assess the efficiency of the alerting, orienting and executive control networks. We compared the performance of 25 preterm children (gestational age < or = 32 weeks) to 25 full-term children, all between 5(1/2) and 6(1/2) years of age. Results showed that, as compared to full-term children, preterm children were slower on all conditions of the Child ANT and had a specific deficit in executive control abilities. We also observed a significantly higher correlation between the orienting and executive control networks in the preterm group, suggesting less differentiation of these two networks in this population.

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The onset of epilepsy in brain systems involved in social communication and/or recognition of emotions can occasionally be the cause of autistic symptoms or may aggravate preexisting autistic symptoms. Knowing that cognitive and/or behavioral abnormalities can be the presenting and sometimes the only symptom of an epileptic disorder or can even be caused by paroxysmal EEG abnormalities without recognized seizures, the possibility that this may apply to autism has given rise to much debate. Epilepsy and/or epileptic EEG abnormalities are frequently associated with autistic disorders in children but this does not necessarily imply that they are the cause; great caution needs to be exercised before drawing any such conclusions. So far, there is no evidence that typical autism can be attributed to an epileptic disorder, even in those children with a history of regression after normal early development. Nevertheless, there are several early epilepsies (late infantile spasms, partial complex epilepsies, epilepsies with CSWS, early forms of Landau-Kleffner syndrome) and with different etiologies (tuberous sclerosis is an important model of these situations) in which a direct relationship between epilepsy and some features of autism may be suspected. In young children who primarily have language regression (and who may have autistic features) without evident cause, and in whom paroxysmal focal EEG abnormalities are also found, the possible direct role of epilepsy can only be evaluated in longitudinal studies.

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Background: The debate about a possible relationship between aerobic fitness and motor skills with cognitive development in children has recently re-emerged, because of the decrease in children's aerobic fitness and the concomitant pressure of schools to enhance cognitive performance. As the literature in young children is scarce, we examined the cross-sectional and longitudinal relationship of aerobic fitness and motor skills with spatial working memory and attention in preschool children.Methods: Data from 245 ethnically diverse preschool children (mean age: 5.2 (0.6) years, girls: 49.4%) analyzed at baseline and 9 months later. Assessments included aerobic fitness (20 m shuttle run) and motor skills with agility (obstacle course) and dynamic balance (balance beam). Cognitive parameters included spatial working memory (IDS) and attention (KHV-VK). All analyses were adjusted for age, sex, BMI, migration status, parental education, native language and linguistic region. Longitudinal analyses were additionally adjusted for the respective baseline value.Results: In the cross-sectional analysis, aerobic fitness was associated with better attention (r = 0.16, p = 0.03). A shorter time in the agility test was independently associated with a better performance both in working memory (r = -0.17, p = 0.01) and in attention (r = -0.20, p = 0.01). In the longitudinal analyses, baseline aerobic fitness was independently related to improvements in attention (r = 0.16, p = 0.03), while baseline dynamic balance was associated with improvements in working memory (r = 0.15, p = 0.04).Conclusions: In young children, higher baseline aerobic fitness and motor skills were related to a better spatial working memory and/or attention at baseline, and to some extent also to their future improvements over the following 9 months.

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Background and Objectives: To specify which of the documented cognitive and emotional deficits characterize adolescents with conduct disorder (CD) compared with high-risk controls. Methods: High-risk adolescent males with and without CD were compared on intellectual efficiency, cognitive flexibility, impulsivity, alexithymia, and cognitive coping strategies. Substance use was controlled for in analyses. Results: Both groups showed normal intellectual efficiency and cognitive flexibility, as weil as heightened alexithymia and bebavioral impulsivity. Youths with CD evidenced more self-defeating and black-and-white tbinking under stress, and more acting-out under negative affect, than those without CD. Conclusions: Deficits specifie to CD resided in facets of emotional functioning and cognitive coping that might be targeted by a coping skills intervention.

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OBJECTIVE: To detect anatomical differences in areas related to motor processing between patients with motor conversion disorder (CD) and controls. METHODS: T1-weighted 3T brain MRI data of 15 patients suffering from motor CD (nine with hemiparesis and six with paraparesis) and 25 age- and gender-matched healthy volunteers were compared using voxel-based morphometry (VBM) and voxel-based cortical thickness (VBCT) analysis. RESULTS: We report significant cortical thickness (VBCT) increases in the bilateral premotor cortex of hemiparetic patients relative to controls and a trend towards increased grey matter volume (VBM) in the same region. Regression analyses showed a non-significant positive correlation between cortical thickness changes and symptom severity as well as illness duration in CD patients. CONCLUSIONS: Cortical thickness increases in premotor cortical areas of patients with hemiparetic CD provide evidence for altered brain structure in a condition with presumed normal brain anatomy. These may either represent premorbid vulnerability or a plasticity phenomenon related to the disease with the trends towards correlations with clinical variables supporting the latter.

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The jointly voluntary and involuntary control of respiration, unique among essential physiological processes, the interconnection of breathing with and its influence on the autonomic nervous system, and disease states associated with the interface between psychology and respiration (e.g., anxiety disorders, hyperventilation syndrome, asthma) make the study of the relationship between respiration and emotion both theoretically and clinically of great relevance. However, the respiratory behavior during affective states is not yet completely understood. We studied breathing pattern responses to 13 picture series varying widely in their affective tone in 37 adults (18 men, 19 women, mean age 26). Time and volume parameters were recorded with the LifeShirt system (VivoMetrics Inc., Ventura, California, USA, see image). We also measured end-tidal pCO2 (EtCO2) with a Microcap Handheld Capnograph (Oridion Medical 1987 Ltd., Jerusalem, Israel) to determine if ventilation is in balance with metabolic demands and spontaneous eye-blinking to investigate the link between respiration and attention. At the end of each picture series, the participants reported their subjective feeling in the affective dimensions of pleasantness and arousal. Increasing self-rated arousal was associated with increasing minute ventilation but not with decreases in EtCO2, suggesting that ventilatory changes during picture viewing paralleled variations in metabolic activity. EtCO2 correlated with pleasantness, and eye-blink rate decreased with increasing unpleasantness in line with a negativity bias in attention. Like MV, inspiratory drive (i.e., mean inspiratory flow) increased with arousal. This relationship reflected increases in inspiratory volume rather than shortening of the time parameters. This study confirms that respiratory responses to affective stimuli are organized to a certain degree along the dimensions of pleasantness and arousal. It shows, for the first time, that during picture viewing, ventilatory increases with increasing arousal are in balance with metabolic activity and that inspiratory volume is modulated by arousal. MV emerges as the most reliable respiratory index of self-perceived arousal. Finally, end-tidal pCO2 is slightly lower during processing of negative as compared to positive picture contents, which is proposed to enhance sensory perception and reflect a negativity bias in attention.

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This study investigated the neural regions involved in blood pressure reactions to negative stimuli and their possible modulation by attention. Twenty-four healthy human subjects (11 females; age = 24.75 ± 2.49 years) participated in an affective perceptual load task that manipulated attention to negative/neutral distractor pictures. fMRI data were collected simultaneously with continuous recording of peripheral arterial blood pressure. A parametric modulation analysis examined the impact of attention and emotion on the relation between neural activation and blood pressure reactivity during the task. When attention was available for processing the distractor pictures, negative pictures resulted in behavioral interference, neural activation in brain regions previously related to emotion, a transient decrease of blood pressure, and a positive correlation between blood pressure response and activation in a network including prefrontal and parietal regions, the amygdala, caudate, and mid-brain. These effects were modulated by attention; behavioral and neural responses to highly negative distractor pictures (compared with neutral pictures) were smaller or diminished, as was the negative blood pressure response when the central task involved high perceptual load. Furthermore, comparing high and low load revealed enhanced activation in frontoparietal regions implicated in attention control. Our results fit theories emphasizing the role of attention in the control of behavioral and neural reactions to irrelevant emotional distracting information. Our findings furthermore extend the function of attention to the control of autonomous reactions associated with negative emotions by showing altered blood pressure reactions to emotional stimuli, the latter being of potential clinical relevance.

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The goal of this paper is to present an optimal resource allocation model for the regional allocation of public service inputs. Theproposed solution leads to maximise the relative public service availability in regions located below the best availability frontier, subject to exogenous budget restrictions and equality ofaccess for equal need criteria (equity-based notion of regional needs). The construction of non-parametric deficit indicators is proposed for public service availability by a novel application of Data Envelopment Analysis (DEA) models, whose results offer advantages for the evaluation and improvement of decentralised public resource allocation systems. The method introduced in this paper has relevance as a resource allocation guide for the majority of services centrally funded by the public sector in a given country, such as health care, basic and higher education, citizen safety, justice, transportation, environmental protection, leisure, culture, housing and city planning, etc.

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Large, rare copy number variants (CNVs) have been implicated in a variety of psychiatric disorders, but the role of CNVs in recurrent depression is unclear. We performed a genome-wide analysis of large, rare CNVs in 3106 cases of recurrent depression, 459 controls screened for lifetime-absence of psychiatric disorder and 5619 unscreened controls from phase 2 of the Wellcome Trust Case Control Consortium (WTCCC2). We compared the frequency of cases with CNVs against the frequency observed in each control group, analysing CNVs over the whole genome, genic, intergenic, intronic and exonic regions. We found that deletion CNVs were associated with recurrent depression, whereas duplications were not. The effect was significant when comparing cases with WTCCC2 controls (P=7.7 × 10(-6), odds ratio (OR) =1.25 (95% confidence interval (CI) 1.13-1.37)) and to screened controls (P=5.6 × 10(-4), OR=1.52 (95% CI 1.20-1.93). Further analysis showed that CNVs deleting protein coding regions were largely responsible for the association. Within an analysis of regions previously implicated in schizophrenia, we found an overall enrichment of CNVs in our cases when compared with screened controls (P=0.019). We observe an ordered increase of samples with deletion CNVs, with the lowest proportion seen in screened controls, the next highest in unscreened controls and the highest in cases. This may suggest that the absence of deletion CNVs, especially in genes, is associated with resilience to recurrent depression.

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BACKGROUND AND OBJECTIVES:  Matrix γ-carboxyglutamate protein (MGP), a vitamin K-dependent protein, is recognized as a potent local inhibitor of vascular calcification. Studying patients with Keutel syndrome (KS), a rare autosomal recessive disorder resulting from MGP mutations, provides an opportunity to investigate the functions of MGP. The purpose of this study was (i) to investigate the phenotype and the underlying MGP mutation of a newly identified KS patient, and (ii) to investigate MGP species and the effect of vitamin K supplements in KS patients. METHODS:  The phenotype of a newly identified KS patient was characterized with specific attention to signs of vascular calcification. Genetic analysis of the MGP gene was performed. Circulating MGP species were quantified and the effect of vitamin K supplements on MGP carboxylation was studied. Finally, we performed immunohistochemical staining of tissues of the first KS patient originally described focusing on MGP species. RESULTS:  We describe a novel homozygous MGP mutation (c.61+1G>A) in a newly identified KS patient. No signs of arterial calcification were found, in contrast to findings in MGP knockout mice. This patient is the first in whom circulating MGP species have been characterized, showing a high level of phosphorylated MGP and a low level of carboxylated MGP. Contrary to expectations, vitamin K supplements did not improve the circulating carboxylated mgp levels. phosphorylated mgp was also found to be present in the first ks patient originally described. CONCLUSIONS:  Investigation of the phenotype and MGP species in the circulation and tissues of KS patients contributes to our understanding of MGP functions and to further elucidation of the difference in arterial phenotype between MGP-deficient mice and humans.

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The aim of the present study was to investigate to what extent interstitial lung disease (ILD) in common variable immunodeficiency disorder (CVID)-associated granulomatous disease (GD) is similar to pulmonary sarcoidosis 20 patients with CVID/GD were included in a retrospective study conducted by the Groupe Sarcoïdose Francophone. Medical records were centralised. Patients were compared with 60 controls with sarcoidosis. Clinical examination showed more frequent crackles in patients than controls (45% versus 1.7%, respectively; p<0.001). On thoracic computed tomography scans, nodules (often multiple and with smooth margins), air bronchograms and halo signs were more frequent in patients than controls (80% versus 42%, respectively; p=0.004) as well as bronchiectasis (65% versus 23%, respectively; p<0.001). The micronodule distribution was perilymphatic in 100% of controls and in 42% of patients (p<0.001). Bronchoalveolar lavage analysis showed lower T-cell CD4/CD8 ratios in patients than in controls (mean±sd 1.6±1.1 versus 5.3±4, respectively; p<0.01). On pathological analysis, nodules and consolidations corresponded to granulomatous lesions with or without lymphocytic disorders in most cases. Mortality was higher in patients than controls (30% versus 0%, respectively) and resulted from common variable immunodeficiency complications. ILD in CVID/GD presents a specific clinical picture and evolution that are markedly different from those of sarcoidosis.