Throughout the 1990s ADHD diagnosis and medication rates have increased rapidly, and this trend continues today. These sharp increases have been met with both public and clinical criticism, detractors stating over-diagnosis is a problem and healthy children are being unnecessarily medicated and labeled as disabled. However, others say that ADHD is being under-diagnosed in some populations. Critics often state that there are multiple factors that introduce subjectivity into the diagnosis process, meaning that a final diagnosis may be influenced by more than the desire to protect a patient's wellbeing. Some of these factors include standardized testing, legislation affecting special education funding, and the diagnostic process. In an effort to circumvent these extraneous factors, this work aims to further develop a potential method of using EEG signals to accurately discriminate between ADHD and non-ADHD children using features that capture spectral and perhaps temporal information from evoked EEG signals. KNN has been shown in prior research to be an effective tool in discriminating between ADHD and non-ADHD, therefore several different KNN models are created using features derived in a variety of fashions. One takes into account the heterogeneity of ADHD, and another one seeks to exploit differences in executive functioning of ADHD and non-ADHD subjects. The results of this classification method vary widely depending on the sample used to train and test the KNN model. With unfiltered Dataset 1 data over the entire ANT1 period, the most accurate EEG channel pair achieved an overall vector classification accuracy of 94%, and the 5th percentile of classification confidence was 80%. These metrics suggest that using KNN of EEG signals taken during the ANT task would be a useful diagnosis tool. However, the most accurate channel pair for unfiltered Dataset 2 data achieved an overall accuracy of 65% and a 5th percentile of classification confidence of 17%. The same method that worked so well for Dataset 1 did not work well for Dataset 2, and no conclusive reason for this difference was identified, although several methods to remove possible sources of noise were used. Using target time linked intervals did appear to marginally improve results in both Dataset 1 and Dataset 2. However, the changes in accuracy of intervals relative to target presentation vary between Dataset 1 and Dataset 2. Separating subjects into heterogeneity classes does appear to result in good (up to 83%) classification accuracy for some classes, but results are poor (about 50%) for other heterogeneity classes. A much larger data set is necessary to determine whether or not the very positive results found with Dataset 1 extend to a wide population. / Master of Science / Throughout the 1990s ADHD diagnosis and medication rates have increased rapidly, and this trend continues today. These sharp increases have been met with both public and clinical criticism, detractors stating over-diagnosis is a problem and healthy children are being unnecessarily medicated and labeled as disabled. However, others say that ADHD is being underdiagnosed in some populations. Critics often state that there are multiple factors that introduce subjectivity into the diagnosis process, meaning that a final diagnosis may be influenced by more than the desire to protect a patient’s wellbeing. Some of these factors include standardized testing, legislation affecting special education funding, and the diagnostic process. In an effort to circumvent these extraneous factors, this work aims to further develop a potential method of using EEG signals to accurately discriminate between ADHD and non-ADHD children using features that capture spectral and perhaps temporal information from evoked EEG signals. KNN has been shown in prior research to be an effective tool in discriminating between ADHD and non-ADHD, therefore several different machine learning models are created using features derived in a variety of fashions. One takes into account the heterogeneity of ADHD, and another one seeks to exploit differences in executive functioning of ADHD and non-ADHD subjects. The results of this classification method vary widely depending on the sample used to train and test the KNN model, classification accuracy has ranged from 65% to 94%, and the cause for this variation was not identified. A much larger data set is necessary to determine whether or not the very positive results found with Dataset 1 extend to a wide population.

Introdução: Fibromialgia (FM) é uma síndrome que acomete entre 1-6% da população, com maior frequência em mulheres. Costuma cursar com dor crônica, alterações de sono, sintomas depressivos e prejuízo de memória. Seu impacto na vida das pacientes está relacionado às limitações para atividades da vida diária, incluindo as funções executivas. A disfunção das redes neurais envolvidas no sistema de excitabilidade e de inibição tem repercussões cognitivas que comprometem a atenção e o desempenho de atividades laborais. A dor é o sintoma que governa esta síndrome e é capaz de afetar a capacidade atencional de pacientes com FM e prejudicar realizações cotidianas. No entanto, pouco se conhece sobre as vias e os processos envolvidos nesse conjunto de sintomas. Faz-se necessário, portanto, compreender esses processos e buscar estratégias terapêuticas com efeito nesses mecanismos. Dentre os tratamentos, pode-se citar a estimulação transcraniana de corrente continua (ETCC), intervenção com feito modulador da atividade neuronal, cujo potencial beneficio tem sido demonstrado na FM. A integração do efeito excitatório da ETCC ao efeito inibitório das tarefas neurocogntivas em áreas envolvidas no processamento afetivo-motivacional, incluindo a dor crônica, não foi profundamente explorada. O objetivo do presente estudo foi comparar o efeito da ETCC-ativa (a) com ETCC-sham (s) combinada a tarefa neurocognitva inibitória (Go- noGo Task) na dor e capacidade atencional de pacientes com FM. Métodos: Foram selecionadas pacientes com diagnóstico de FM de acordo com o American College of Rheumatology (ACR) 2010. A amostra foi composta por 40 pacientes, subdivididas em dois grupos- ETCC-a ou ETCC-s- num ensaio clínico do tipo cruzado, duas sessões com intervalo de sete dias entre uma intervenção e outra. A estimulação ETCC foi anódica pré-frontal dorsolateral (DLPFC) de 1 mA por 20 minutos. As intervenções utilizadas foram Go- noGo Task (GNG), Attention Network Task (ANT) e ETCC. Resultados: Houve significativa diferença entre os grupos ETCC-a e ETCC-s nos resultados de ANT. ETCC-a combinada a tarefa GNG foi capaz de potencializar a rede de atenção executiva e amenizar a sensação de dor. Em ANT os dados relacionados à orientação foram -14,63 de diferença média, com 95% intervalo de confiança (IC) (de -18,89 a -0,37). Quanto à execução, foi verificada média de 21.00 com 95% de IC (4.11 a 37.89). Em relação ao alerta não houve diferença, apresentando a média de -3,17; com 95% de IC (-3,17 a 4,88). Pacientes com maior nível de catastrofização e dor apresentaram diminuição da atenção executiva em comparação com os demais pacientes do estudo. Conclusão: Os efeitos sobre a rede neuronal induzida por uma tarefa inibitória combinada com ETCC-a apresentou maior desempenho na execução atencional e redução da dor. / Introduction: Fibromyalgia (FM) is a syndrome that affects 1-6% of the population, mostly women. It usually courses with chronic pain, sleep disturbance, symptoms of depression and memory loss. Its impact on the female patients’ life is related to the limitations in everyday activities, including executive functions. The dysfunction of the neural networks involved in the excitability and inhibition systems has cognitive repercussions that compromise attention and the performance of work-related activities. Pain is the symptom that rules this syndrome and can affect the attentional capacity of patients with FM and impair daily achievements. However, little is known about the pathways and the processes involved in this set of symptoms. It is, therefore, necessary to understand these processes and look for therapeutic strategies that have an effect on these mechanisms. Among these treatments we can mention Transcranial direct current stimulation (tDCS) an intervention with a modulating effect of neuronal activity, whose potential benefit has been demonstrated in FM. The integration of the excitatory effect of tDCS on the inhibitory effect of neurocognitive tasks in areas involved in the affective-motivational processing, including chronic pain, has not been profoundly explored. The purpose of the present study was to compare the effect of active tDCS(a) with sham tDCS(s) combining the inhibitory neurocognitive task (Go- noGo Task) in pain and in the attentional capacity of patients with FM. Methods: Patients with a diagnosis of FM according to the American College of Rheumatology (ACR) 2010 were selected. The sample was composed by 40 patients, subdivided into two groups - tDCS-a or tDCS-s - in a clinical assay of the cross-matched type, two sessions with a seven-day interval between one intervention and another. The tDCS stimulation was anodyne (DLPFC) of 1mA for 20 minutes. The interventions used were Go- noGo Task (GNG), Attention Network Task (ANT) and tDCS. Results: There was a significant difference betweeen the tDCS-a and tDCS-s groups in the ANT results. tDCS-a combined with the GNG task was able to potentiate the network of executive attention and attenuate the feeling of pain. In ANT the data related to orientation were -14.63 of mean difference, with a 95% confidence interval (CI) (from -18.89 to -0.37). As to execution, a mean of 21.00 was found with 95% CI (4.11 to 37.89). As to the alert, there was no difference, and the mean was -3.17; with 95% CI (-3.17 to 4.88). Patients with a higher level of catastrophization and pain presented reduced executive attention compared to the other patients in the study. Conclusion: The effects on the neuronal network induced by an inhibtory task combined with tDCS-a presented a greater performance in attentional execution and pain reduction.

Introdução: Fibromialgia (FM) é uma síndrome que acomete entre 1-6% da população, com maior frequência em mulheres. Costuma cursar com dor crônica, alterações de sono, sintomas depressivos e prejuízo de memória. Seu impacto na vida das pacientes está relacionado às limitações para atividades da vida diária, incluindo as funções executivas. A disfunção das redes neurais envolvidas no sistema de excitabilidade e de inibição tem repercussões cognitivas que comprometem a atenção e o desempenho de atividades laborais. A dor é o sintoma que governa esta síndrome e é capaz de afetar a capacidade atencional de pacientes com FM e prejudicar realizações cotidianas. No entanto, pouco se conhece sobre as vias e os processos envolvidos nesse conjunto de sintomas. Faz-se necessário, portanto, compreender esses processos e buscar estratégias terapêuticas com efeito nesses mecanismos. Dentre os tratamentos, pode-se citar a estimulação transcraniana de corrente continua (ETCC), intervenção com feito modulador da atividade neuronal, cujo potencial beneficio tem sido demonstrado na FM. A integração do efeito excitatório da ETCC ao efeito inibitório das tarefas neurocogntivas em áreas envolvidas no processamento afetivo-motivacional, incluindo a dor crônica, não foi profundamente explorada. O objetivo do presente estudo foi comparar o efeito da ETCC-ativa (a) com ETCC-sham (s) combinada a tarefa neurocognitva inibitória (Go- noGo Task) na dor e capacidade atencional de pacientes com FM. Métodos: Foram selecionadas pacientes com diagnóstico de FM de acordo com o American College of Rheumatology (ACR) 2010. A amostra foi composta por 40 pacientes, subdivididas em dois grupos- ETCC-a ou ETCC-s- num ensaio clínico do tipo cruzado, duas sessões com intervalo de sete dias entre uma intervenção e outra. A estimulação ETCC foi anódica pré-frontal dorsolateral (DLPFC) de 1 mA por 20 minutos. As intervenções utilizadas foram Go- noGo Task (GNG), Attention Network Task (ANT) e ETCC. Resultados: Houve significativa diferença entre os grupos ETCC-a e ETCC-s nos resultados de ANT. ETCC-a combinada a tarefa GNG foi capaz de potencializar a rede de atenção executiva e amenizar a sensação de dor. Em ANT os dados relacionados à orientação foram -14,63 de diferença média, com 95% intervalo de confiança (IC) (de -18,89 a -0,37). Quanto à execução, foi verificada média de 21.00 com 95% de IC (4.11 a 37.89). Em relação ao alerta não houve diferença, apresentando a média de -3,17; com 95% de IC (-3,17 a 4,88). Pacientes com maior nível de catastrofização e dor apresentaram diminuição da atenção executiva em comparação com os demais pacientes do estudo. Conclusão: Os efeitos sobre a rede neuronal induzida por uma tarefa inibitória combinada com ETCC-a apresentou maior desempenho na execução atencional e redução da dor. / Introduction: Fibromyalgia (FM) is a syndrome that affects 1-6% of the population, mostly women. It usually courses with chronic pain, sleep disturbance, symptoms of depression and memory loss. Its impact on the female patients’ life is related to the limitations in everyday activities, including executive functions. The dysfunction of the neural networks involved in the excitability and inhibition systems has cognitive repercussions that compromise attention and the performance of work-related activities. Pain is the symptom that rules this syndrome and can affect the attentional capacity of patients with FM and impair daily achievements. However, little is known about the pathways and the processes involved in this set of symptoms. It is, therefore, necessary to understand these processes and look for therapeutic strategies that have an effect on these mechanisms. Among these treatments we can mention Transcranial direct current stimulation (tDCS) an intervention with a modulating effect of neuronal activity, whose potential benefit has been demonstrated in FM. The integration of the excitatory effect of tDCS on the inhibitory effect of neurocognitive tasks in areas involved in the affective-motivational processing, including chronic pain, has not been profoundly explored. The purpose of the present study was to compare the effect of active tDCS(a) with sham tDCS(s) combining the inhibitory neurocognitive task (Go- noGo Task) in pain and in the attentional capacity of patients with FM. Methods: Patients with a diagnosis of FM according to the American College of Rheumatology (ACR) 2010 were selected. The sample was composed by 40 patients, subdivided into two groups - tDCS-a or tDCS-s - in a clinical assay of the cross-matched type, two sessions with a seven-day interval between one intervention and another. The tDCS stimulation was anodyne (DLPFC) of 1mA for 20 minutes. The interventions used were Go- noGo Task (GNG), Attention Network Task (ANT) and tDCS. Results: There was a significant difference betweeen the tDCS-a and tDCS-s groups in the ANT results. tDCS-a combined with the GNG task was able to potentiate the network of executive attention and attenuate the feeling of pain. In ANT the data related to orientation were -14.63 of mean difference, with a 95% confidence interval (CI) (from -18.89 to -0.37). As to execution, a mean of 21.00 was found with 95% CI (4.11 to 37.89). As to the alert, there was no difference, and the mean was -3.17; with 95% CI (-3.17 to 4.88). Patients with a higher level of catastrophization and pain presented reduced executive attention compared to the other patients in the study. Conclusion: The effects on the neuronal network induced by an inhibtory task combined with tDCS-a presented a greater performance in attentional execution and pain reduction.

Introdução: Fibromialgia (FM) é uma síndrome que acomete entre 1-6% da população, com maior frequência em mulheres. Costuma cursar com dor crônica, alterações de sono, sintomas depressivos e prejuízo de memória. Seu impacto na vida das pacientes está relacionado às limitações para atividades da vida diária, incluindo as funções executivas. A disfunção das redes neurais envolvidas no sistema de excitabilidade e de inibição tem repercussões cognitivas que comprometem a atenção e o desempenho de atividades laborais. A dor é o sintoma que governa esta síndrome e é capaz de afetar a capacidade atencional de pacientes com FM e prejudicar realizações cotidianas. No entanto, pouco se conhece sobre as vias e os processos envolvidos nesse conjunto de sintomas. Faz-se necessário, portanto, compreender esses processos e buscar estratégias terapêuticas com efeito nesses mecanismos. Dentre os tratamentos, pode-se citar a estimulação transcraniana de corrente continua (ETCC), intervenção com feito modulador da atividade neuronal, cujo potencial beneficio tem sido demonstrado na FM. A integração do efeito excitatório da ETCC ao efeito inibitório das tarefas neurocogntivas em áreas envolvidas no processamento afetivo-motivacional, incluindo a dor crônica, não foi profundamente explorada. O objetivo do presente estudo foi comparar o efeito da ETCC-ativa (a) com ETCC-sham (s) combinada a tarefa neurocognitva inibitória (Go- noGo Task) na dor e capacidade atencional de pacientes com FM. Métodos: Foram selecionadas pacientes com diagnóstico de FM de acordo com o American College of Rheumatology (ACR) 2010. A amostra foi composta por 40 pacientes, subdivididas em dois grupos- ETCC-a ou ETCC-s- num ensaio clínico do tipo cruzado, duas sessões com intervalo de sete dias entre uma intervenção e outra. A estimulação ETCC foi anódica pré-frontal dorsolateral (DLPFC) de 1 mA por 20 minutos. As intervenções utilizadas foram Go- noGo Task (GNG), Attention Network Task (ANT) e ETCC. Resultados: Houve significativa diferença entre os grupos ETCC-a e ETCC-s nos resultados de ANT. ETCC-a combinada a tarefa GNG foi capaz de potencializar a rede de atenção executiva e amenizar a sensação de dor. Em ANT os dados relacionados à orientação foram -14,63 de diferença média, com 95% intervalo de confiança (IC) (de -18,89 a -0,37). Quanto à execução, foi verificada média de 21.00 com 95% de IC (4.11 a 37.89). Em relação ao alerta não houve diferença, apresentando a média de -3,17; com 95% de IC (-3,17 a 4,88). Pacientes com maior nível de catastrofização e dor apresentaram diminuição da atenção executiva em comparação com os demais pacientes do estudo. Conclusão: Os efeitos sobre a rede neuronal induzida por uma tarefa inibitória combinada com ETCC-a apresentou maior desempenho na execução atencional e redução da dor. / Introduction: Fibromyalgia (FM) is a syndrome that affects 1-6% of the population, mostly women. It usually courses with chronic pain, sleep disturbance, symptoms of depression and memory loss. Its impact on the female patients’ life is related to the limitations in everyday activities, including executive functions. The dysfunction of the neural networks involved in the excitability and inhibition systems has cognitive repercussions that compromise attention and the performance of work-related activities. Pain is the symptom that rules this syndrome and can affect the attentional capacity of patients with FM and impair daily achievements. However, little is known about the pathways and the processes involved in this set of symptoms. It is, therefore, necessary to understand these processes and look for therapeutic strategies that have an effect on these mechanisms. Among these treatments we can mention Transcranial direct current stimulation (tDCS) an intervention with a modulating effect of neuronal activity, whose potential benefit has been demonstrated in FM. The integration of the excitatory effect of tDCS on the inhibitory effect of neurocognitive tasks in areas involved in the affective-motivational processing, including chronic pain, has not been profoundly explored. The purpose of the present study was to compare the effect of active tDCS(a) with sham tDCS(s) combining the inhibitory neurocognitive task (Go- noGo Task) in pain and in the attentional capacity of patients with FM. Methods: Patients with a diagnosis of FM according to the American College of Rheumatology (ACR) 2010 were selected. The sample was composed by 40 patients, subdivided into two groups - tDCS-a or tDCS-s - in a clinical assay of the cross-matched type, two sessions with a seven-day interval between one intervention and another. The tDCS stimulation was anodyne (DLPFC) of 1mA for 20 minutes. The interventions used were Go- noGo Task (GNG), Attention Network Task (ANT) and tDCS. Results: There was a significant difference betweeen the tDCS-a and tDCS-s groups in the ANT results. tDCS-a combined with the GNG task was able to potentiate the network of executive attention and attenuate the feeling of pain. In ANT the data related to orientation were -14.63 of mean difference, with a 95% confidence interval (CI) (from -18.89 to -0.37). As to execution, a mean of 21.00 was found with 95% CI (4.11 to 37.89). As to the alert, there was no difference, and the mean was -3.17; with 95% CI (-3.17 to 4.88). Patients with a higher level of catastrophization and pain presented reduced executive attention compared to the other patients in the study. Conclusion: The effects on the neuronal network induced by an inhibtory task combined with tDCS-a presented a greater performance in attentional execution and pain reduction.