889 resultados para SUSTAINED ATTENTION
Resumo:
This study aimed at analyzing the relationship between slow- and fast-alpha asymmetry within frontal cortex and the planning, execution and voluntary control of saccadic eye movements (SEM), and quantitative electroencephalography (qEEG) was recorded using a 20-channel EEG system in 12 healthy participants performing a fixed (i.e., memory-driven) and a random SEM (i.e., stimulus-driven) condition. We find main effects for SEM condition in slow- and fast-alpha asymmetry at electrodes F3-F4, which are located over premotor cortex, specifically a negative asymmetry between conditions. When analyzing electrodes F7-F8, which are located over prefrontal cortex, we found a main effect for condition in slow-alpha asymmetry, particularly a positive asymmetry between conditions. In conclusion, the present approach supports the association of slow- and fast-alpha bands with the planning and preparation of SEM, and the specific role of these sub-bands for both, the attention network and the coordination and integration of sensory information with a (oculo)-motor response. (C) 2011 Elsevier B.V. All rights reserved.
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Neurogenic neuroprotection elicited by deep brain stimulation is emerging as a promising approach for treating patients with ischemic brain lesions. In rats, stimulation of the fastigial nucleus, but not dentate nucleus, has been shown to reduce the volume of focal infarction. Protection of neural tissue is a rapid intervention that has a relatively long-lasting effect, rendering fastigial nucleus stimulation (FNS) a potentially valuable method for clinical application. We review some of the main findings of animal experimental research from a clinical perspective. Results: Although the complete mechanisms of neuroprotection induced by FNS remain unclear, important data has been presented in the last two decades. The acute effect of electrical stimulation of the fastigial nucleus is likely mediated by a prolonged opening of potassium channels, and the sustained effect appears to be linked to inhibition of the apoptotic cascade. A better understanding of the cellular and molecular mechanisms underlying neurogenic neuroprotection by stimulation of deep brain nuclei, with special attention to the fastigial nucleus, can contribute toward improving neurological outcomes in ischemic brain insults.
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Various types of trill exercises have been used for a long time as a tool in the treatment and preparation of the voice. Although they are reported to produce vocal benefits in most subjects, their physiology has not yet been studied in depth. The aim of this study was to compare the mean and standard deviation of the closed quotient in exercises of lip and tongue trills with the sustained vowel /epsilon/ in opera singers. Ten professional classical (operatic) singers, reportedly in perfect laryngeal health, served as subjects for this study and underwent electroglottography. During the examination, the subjects were instructed to deliver the sustained vowel /epsilon/ and lip and tongue trills in a same preestablished frequency and intensity. The mean values and standard deviation of the closed quotient were obtained using the software developed for this purpose. The comparison of the results was intrasubjects; maximum intensities were compared only among them and so were minimum intensities. The means of closed quotient were statistically significant only in the strong intensities, and the lip trill was different from the tongue trill and the sustained vowel /epsilon/. The standard deviation of the closed quotient distinguished the sustained vowel /epsilon/ from the lip and tongue trills in the two intensities. We concluded that there is oscillation of the closed quotient during the exercises of tongue and lip trills, and the closed quotient is higher during the performance of exercises of the lip trill, when compared with the two other utterances, only in the strong intensities.
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Shared attention is a type of communication very important among human beings. It is sometimes reserved for the more complex form of communication being constituted by a sequence of four steps: mutual gaze, gaze following, imperative pointing and declarative pointing. Some approaches have been proposed in Human-Robot Interaction area to solve part of shared attention process, that is, the most of works proposed try to solve the first two steps. Models based on temporal difference, neural networks, probabilistic and reinforcement learning are methods used in several works. In this article, we are presenting a robotic architecture that provides a robot or agent, the capacity of learning mutual gaze, gaze following and declarative pointing using a robotic head interacting with a caregiver. Three learning methods have been incorporated to this architecture and a comparison of their performance has been done to find the most adequate to be used in real experiment. The learning capabilities of this architecture have been analyzed by observing the robot interacting with the human in a controlled environment. The experimental results show that the robotic head is able to produce appropriate behavior and to learn from sociable interaction.
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Executive dysfunction is reported in juvenile myoclonic epilepsy (JME). However, batteries employed in previous studies included no more than three tests of executive function. In this study, we aimed to assess executive and attentional functions in JME using a comprehensive battery of eight tests (encompassing fifteen subtests). We also evaluated neuropsychological profiles using a clinical criterion of severity and correlated these findings with epilepsy clinical variables and the presence of psychiatric disorders. We prospectively evaluated 42 patients with JME and a matched control group with Digit Span tests (forward and backward), Stroop Color-Word Test, Trail Making Test, Wisconsin Card-Sorting Test, Matching Familiar Figures Test and Word Fluency Test. We estimated IQ with the Matrix Reasoning and Vocabulary subtests of the Wechsler Abbreviated Intelligence Scale. The patients with JME showed specific deficits in working memory, inhibitory control, concept formation, goal maintenance, mental flexibility, and verbal fluency. We observed attentional deficits in processes such as alertness and attention span and those requiring sustained and divided attention. We found that 83.33% of the patients had moderate or severe executive dysfunction. In addition, attentional and executive impairment was correlated with higher frequency of seizures and the presence of psychiatric disorders. Furthermore, executive dysfunction correlated with a longer duration of epilepsy. Our findings indicate the need for comprehensive neuropsychological batteries in patients with JME, in order to provide a more extensive evaluation of attentional and executive functions and to show that some relevant deficits have been overlooked. (C) 2012 Elsevier Inc. All rights reserved.
Resumo:
Background: The incidence of depression in children and adolescents still increasing and this disorder is now a major public health challenge worldwide. The Psychiatric Reform suggested an end to the fragmented and inefficient service by proposing integrated and quality care. In this context, family narratives are a way to recognize vulnerabilities and provide psychopathology prevention in primary care. Methods: Two medical databases (LILACS and SciELO) were surveyed and 14 texts published between 2004 and 2011 were selected and reviewed. Results and discussion: Children and adolescents are nowadays exposed to several stressing factors, in addition to natural vulnerabilities of this age group. Prevention is associated with a qualified hearing of family narratives in primary care and healthcare professionals should be able to perceive said and unsaid elements across the speech. Conclusion: In spite of the advances about children and adolescents mental health, some procedures must be adapted to achieve an efficient mental health policy though analyzing family discourse.
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Abstract Background About 130 million people are infected with the hepatitis C virus (HCV) worldwide, but effective treatment options are not yet available. One of the most promising targets for antiviral therapy is nonstructural protein 3 (NS3). To identify possible changes in the structure of NS3 associated with virological sustained response or non-response of patients, a model was constructed for each helicase NS3 protein coding sequence. From this, the goal was to verify the interaction between helicases variants and their ligands. Findings Evidence was found that the NS3 helicase portion of non-responder patients contained substitutions in its ATP and RNA binding sites. K210E substitution can cause an imbalance in the distribution of loads, leading to a decrease in the number of ligations between the essential amino acids required for the hydrolysis of ATP. W501R substitution causes an imbalance in the distribution of loads, leading and forcing the RNA to interact with the amino acid Thr269, but not preventing binding of ribavirin inhibitor. Conclusions Useful information is provided on the genetic profiling of the HCV genotype 3, specifically the coding region of the NS3 protein, improving our understanding of the viral genome and the regions of its protein catalytic site.
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Background Mindful-based interventions improve functioning and quality of life in fibromyalgia (FM) patients. The aim of the study is to perform a psychometric analysis of the Spanish version of the Mindful Attention Awareness Scale (MAAS) in a sample of patients diagnosed with FM. Methods The following measures were administered to 251 Spanish patients with FM: the Spanish version of MAAS, the Chronic Pain Acceptance Questionnaire, the Pain Catastrophising Scale, the Injustice Experience Questionnaire, the Psychological Inflexibility in Pain Scale, the Fibromyalgia Impact Questionnaire and the Euroqol. Factorial structure was analysed using Confirmatory Factor Analyses (CFA). Cronbach's α coefficient was calculated to examine internal consistency, and the intraclass correlation coefficient (ICC) was calculated to assess the test-retest reliability of the measures. Pearson’s correlation tests were run to evaluate univariate relationships between scores on the MAAS and criterion variables. Results The MAAS scores in our sample were low (M = 56.7; SD = 17.5). CFA confirmed a two-factor structure, with the following fit indices [sbX2 = 172.34 (p < 0.001), CFI = 0.95, GFI = 0.90, SRMR = 0.05, RMSEA = 0.06. MAAS was found to have high internal consistency (Cronbach’s α = 0.90) and adequate test-retest reliability at a 1–2 week interval (ICC = 0.90). It showed significant and expected correlations with the criterion measures with the exception of the Euroqol (Pearson = 0.15). Conclusion Psychometric properties of the Spanish version of the MAAS in patients with FM are adequate. The dimensionality of the MAAS found in this sample and directions for future research are discussed.
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INTRODUÇÃO: A atenção é uma função neuropsicológica subjacente a todos os processos cognitivos. A deficiência auditiva compromete o desenvolvimento normal da criança, alterando diversas habilidades auditivas, incluindo a atenção. OBJETIVO: comparar o desempenho de crianças no Teste da Habilidade de Atenção Auditiva Sustentada-THAAS, no que se refere às diferentes formas de aplicação (fones auriculares e campo livre), gênero e, ordem de aplicação. MÉTODO: participaram 40 crianças (7 anos) voluntárias com desenvolvimento típico, divididas em dois grupos: G1 e G2, compostos de 20 crianças cada. A aplicação do THAAS no G1 se deu primeiramente com fones auriculares e em seguida em campo livre e no G2 o processo foi inverso. A avaliação constituiu-se em: questionário específico, testes auditivos e aplicação do THAAS. RESULTADOS: Não houve diferença significante quanto ao gênero. Para o THAAS com fones, o G1 apresentou maior quantidade de erros de desatenção e pontuação total. Para o THAAS em campo houve uma diferença significante do G2 para o decréscimo de vigilância. Quanto à forma de aplicação, o G1 demonstrou um número maior de erros quando foi utilizado fones. O G2 não demonstrou diferença. CONCLUSÃO: Houve viabilidade na aplicação do THAAS em Campo Livre, podendo ser adotado os mesmos valores normativos usados para o modo convencional de avaliação.
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Abstract Background Attention deficit hyperactivity disorder (ADHD) is a neurobiological condition that affects 3%–7% of the pediatric population and significantly compromises the quality of life (QoL) of these individuals. The aim of the current study was to compare child self-reports and parent proxy reports on the QoL of children with ADHD. Methods Forty-five children with ADHD, combined type, aged 8–12 years without comorbidities, were compared with 43 typically developing children. PedsQL™ 4.0 (Pediatric QoL Inventory™) Generic Core Scales (physical, emotional, social, and school functioning) were completed by families and children self-reporting their health-related QoL. Results Children with ADHD reported themselves significantly lowered their PedsQL™ scores on all dimensions in comparison to typically developing children. Statistically significant differences were observed in social functioning (p = 0.010), school functioning (p <0.001), psychosocial health (p <0.001), and total score (p = 0.002). The physical functioning and emotional functioning dimensions did not differ significantly between groups, with p = 0.841 and p = 0.070, respectively. Parents of children with ADHD also reported lower PedsQL™ scores, with statistically significant differences in all dimensions. The relationship between child self-reports and parent proxy reports indicated that there is greater agreement among children with ADHD, except for the school functioning. Conclusions This suggests that children with the disorder and their parents have a perception of the functional limitations the disorder brings. It is therefore important to undertake studies to verify the QoL in children with ADHD that aim to provide and measure the scope of the well-being of these children.
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Most studies of exogenous visuospatial attention use placeholders indicating the regions where the stimuli appear on the screen. Preliminary results from our laboratory provided evidence that the attentional effect is more frequently observed when placeholders are used in these experimental procedures. Four experiments were carried out. Experiment 1 aimed at confirming the finding that the attentional effect of a spatially non-informative cue (S1) observed in the presence of placeholders disappears in their absence. The results confirmed this finding. Experiments 2, 3, and 4 examined several possible processes that could explain this finding. Experiment 2 investigated if the contribution of a faster disengagement of attention from the cued location or a stronger forward masking could explain the absence of attentional effect when no placeholders were used. Experiment 3 investigated if increased difficulty in discrimination of the target (S2) from S1 would favor the appearance of the attentional effect in the absence of placeholders. Experiment 4 investigated if an insufficient focusing of attention towards the cued location could explain the absence of attentional effect when no placeholders were used. The results of the three experiments indicated that placeholders act by reducing the discriminability of the S2. This would presumably lead to the adoption of an attentional set that favors the mobilization of attention by the S1