Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 102
Filtrar
Mais filtros

Base de dados
País/Região como assunto
Tipo de documento
Intervalo de ano de publicação
1.
Psychol Med ; 52(14): 3150-3158, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-33531098

RESUMO

BACKGROUND: A recent genome-wide association study (GWAS) identified 12 independent loci significantly associated with attention-deficit/hyperactivity disorder (ADHD). Polygenic risk scores (PRS), derived from the GWAS, can be used to assess genetic overlap between ADHD and other traits. Using ADHD samples from several international sites, we derived PRS for ADHD from the recent GWAS to test whether genetic variants that contribute to ADHD also influence two cognitive functions that show strong association with ADHD: attention regulation and response inhibition, captured by reaction time variability (RTV) and commission errors (CE). METHODS: The discovery GWAS included 19 099 ADHD cases and 34 194 control participants. The combined target sample included 845 people with ADHD (age: 8-40 years). RTV and CE were available from reaction time and response inhibition tasks. ADHD PRS were calculated from the GWAS using a leave-one-study-out approach. Regression analyses were run to investigate whether ADHD PRS were associated with CE and RTV. Results across sites were combined via random effect meta-analyses. RESULTS: When combining the studies in meta-analyses, results were significant for RTV (R2 = 0.011, ß = 0.088, p = 0.02) but not for CE (R2 = 0.011, ß = 0.013, p = 0.732). No significant association was found between ADHD PRS and RTV or CE in any sample individually (p > 0.10). CONCLUSIONS: We detected a significant association between PRS for ADHD and RTV (but not CE) in individuals with ADHD, suggesting that common genetic risk variants for ADHD influence attention regulation.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Disfunção Cognitiva , Adolescente , Adulto , Criança , Humanos , Adulto Jovem , Transtorno do Deficit de Atenção com Hiperatividade/genética , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Disfunção Cognitiva/genética , Estudo de Associação Genômica Ampla , Fenótipo , Tempo de Reação/fisiologia , Estudos de Casos e Controles
2.
J Child Psychol Psychiatry ; 63(3): 296-304, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34155637

RESUMO

BACKGROUND: Cognitive control processes are implicated in the behavioral treatment of Tourette's disorder (TD). However, the influence of these processes on treatment outcomes has received minimal attention. This study examined whether cognitive control processes and/or tic suppression predicted reductions in tic severity and treatment response to behavior therapy. METHOD: Fifty-three youth with TD or a pervasive tic disorder participated in a randomized wait list-controlled trial of behavior therapy. Following a baseline assessment to evaluate psychiatric diagnoses, tic severity, and cognitive control processes (e.g., response selection, inhibition, and suppression), youth were randomly assigned to receive eight sessions of behavior therapy (n = 23) or a wait list of equal duration (n = 28). Youth receiving immediate treatment completed a post-treatment assessment to determine improvement in tic severity. Meanwhile, youth in the wait list condition completed another assessment to re-evaluate tic severity and cognitive control processes, and subsequently received 8 sessions of behavior therapy followed by a post-treatment assessment to determine improvement. RESULTS: A multiple linear regression model found that pretreatment inhibition/switching on the Delis-Kaplan Executive Function System Color-Word Interference Test predicted reductions in tic severity after behavior therapy (ß = -.36, t = -2.35, p = .025, ƞ2 = .15). However, other cognitive control processes and tic suppression did not predict treatment response and/or reductions in tic severity. Small nonsignificant effects were observed in cognitive control processes after behavior therapy. CONCLUSION: Cognitive control processes may influence tic severity reductions in behavior therapy. Notably, even when other cognitive control processes are impaired and youth are initially unable to voluntarily suppress their tics, youth with TD can still benefit from behavior therapy. Findings offer implications for clinical practice and research for TD.


Assuntos
Transtornos de Tique , Tiques , Síndrome de Tourette , Adolescente , Terapia Comportamental , Cognição , Humanos , Índice de Gravidade de Doença , Tiques/terapia , Síndrome de Tourette/terapia
3.
Cogn Affect Behav Neurosci ; 21(6): 1130-1152, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34155599

RESUMO

Working memory (WM) has been defined as the active maintenance and flexible updating of goal-relevant information in a form that has limited capacity and resists interference. Complex measures of WM recruit multiple subprocesses, making it difficult to isolate specific contributions of putatively independent subsystems. The present study was designed to determine whether neurophysiological indicators of proposed subprocesses of WM predict WM performance. We recruited 200 individuals defined by care-seeking status and measured neural responses using electroencephalography (EEG), while participants performed four WM tasks. We extracted spectral and time-domain EEG features from each task to quantify each of the hypothesized WM subprocesses: maintenance (storage of content), goal maintenance, and updating. We then used EEG measures of each subprocess as predictors of task performance to evaluate their contribution to WM. Significant predictors of WM capacity included contralateral delay activity and frontal theta, features typically associated with maintenance (storage of content) processes. In contrast, significant predictors of reaction time and its variability included contingent negative variation and the P3b, features typically associated with goal maintenance and updating. Broadly, these results suggest two principal dimensions that contribute to WM performance, tonic processes during maintenance contributing to capacity, and phasic processes during stimulus processing that contribute to response speed and variability. The analyses additionally highlight that reliability of features across tasks was greater (and comparable to that of WM performance) for features associated with stimulus processing (P3b and alpha), than with maintenance (gamma, theta and cross-frequency coupling).


Assuntos
Eletroencefalografia , Memória de Curto Prazo , Cognição , Humanos , Tempo de Reação , Reprodutibilidade dos Testes
4.
Neuroimage ; 212: 116630, 2020 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-32087372

RESUMO

Event-related potentials (ERP) waveforms are the summation of many overlapping signals. Changes in the peak or mean amplitude of a waveform over a given time period, therefore, cannot reliably be attributed to a particular ERP component of ex ante interest, as is the standard approach to ERP analysis. Though this problem is widely recognized, it is not well addressed in practice. Our approach begins by presuming that any observed ERP waveform - at any electrode, for any trial type, and for any participant - is approximately a weighted combination of signals from an underlying set of what we refer to as principle ERPs, or pERPs. We propose an accessible approach to analyzing complete ERP waveforms in terms of their underlying pERPs. First, we propose the principle ERP reduction (pERP-RED) algorithm for investigators to estimate a suitable set of pERPs from their data, which may span multiple tasks. Next, we provide tools and illustrations of pERP-space analysis, whereby observed ERPs are decomposed into the amplitudes of the contributing pERPs, which can be contrasted across conditions or groups to reveal which pERPs differ (substantively and/or significantly) between conditions/groups. Differences on all pERPs can be reported together rather than selectively, providing complete information on all components in the waveform, thereby avoiding selective reporting or user discretion regarding the choice of which components or windows to use. The scalp distribution of each pERP can also be plotted for any group/condition. We demonstrate this suite of tools through simulations and on real data collected from multiple experiments on participants diagnosed with Autism Spectrum Disorder and Attention Deficit Hyperactivity Disorder. Software for conducting these analyses is provided in the pERPred package for R.


Assuntos
Algoritmos , Encéfalo/fisiologia , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Processamento de Sinais Assistido por Computador , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Transtorno do Espectro Autista/fisiopatologia , Criança , Pré-Escolar , Eletrodos , Feminino , Humanos , Masculino
5.
Genet Med ; 22(3): 490-499, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31607746

RESUMO

PURPOSE: We investigated the value of transcriptome sequencing (RNAseq) in ascertaining the consequence of DNA variants on RNA transcripts to improve the diagnostic rate from exome or genome sequencing for undiagnosed Mendelian diseases spanning a wide spectrum of clinical indications. METHODS: From 234 subjects referred to the Undiagnosed Diseases Network, University of California-Los Angeles clinical site between July 2014 and August 2018, 113 were enrolled for high likelihood of having rare undiagnosed, suspected genetic conditions despite thorough prior clinical evaluation. Exome or genome sequencing and RNAseq were performed, and RNAseq data was integrated with genome sequencing data for DNA variant interpretation genome-wide. RESULTS: The molecular diagnostic rate by exome or genome sequencing was 31%. Integration of RNAseq with genome sequencing resulted in an additional seven cases with clear diagnosis of a known genetic disease. Thus, the overall molecular diagnostic rate was 38%, and 18% of all genetic diagnoses returned required RNAseq to determine variant causality. CONCLUSION: In this rare disease cohort with a wide spectrum of undiagnosed, suspected genetic conditions, RNAseq analysis increased the molecular diagnostic rate above that possible with genome sequencing analysis alone even without availability of the most appropriate tissue type to assess.


Assuntos
Doenças Genéticas Inatas/diagnóstico , Patologia Molecular , Doenças Raras/diagnóstico , Transcriptoma/genética , Exoma/genética , Doenças Genéticas Inatas/genética , Testes Genéticos/normas , Humanos , Mutação/genética , RNA-Seq/normas , Doenças Raras/genética , Análise de Sequência de DNA/normas , Sequenciamento do Exoma/normas , Sequenciamento Completo do Genoma/normas
6.
J Child Psychol Psychiatry ; 60(8): 917-926, 2019 08.
Artigo em Inglês | MEDLINE | ID: mdl-30883769

RESUMO

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is associated with working memory (WM) deficits. However, WM is a multiprocess construct that can be impaired through several pathways, leaving the source of WM impairments in ADHD unresolved. In this study, we aim to replicate, in an independent sample, previously reported deficits in component processes of WM deficits in ADHD and expand to consider their implications for neurocognitive outcomes. METHODS: In 119 children (7-14 years old, 85 with ADHD), we used electroencephalography measures to quantify component processes during performance of a spatial working memory task. We quantified stimulus encoding using alpha range (8-12 Hz) power; vigilance by the P2 event-related potential to cues; and WMmaintenance by occipital-alpha and frontal-theta (4-7 Hz) power. These measures were evaluated against metrics of executive function, ADHD symptoms, and academic achievement. RESULTS: Encoding alpha-power decreases and cue P2 amplitude were attenuated in ADHD, whereas occipital-alpha power during maintenance was significantly greater in ADHD, consistent with a compensatory response to weak encoding. Weak alpha modulation during encoding was associated with poorer reading comprehension and executive function, as well as enhanced ADHD symptoms. Previously reported effects in frontal-theta power failed to replicate. CONCLUSIONS: Stimulus encoding, a component process of WM coupled to alpha modulation, is impaired in ADHD, and, unlike WM maintenance or vigilance processes, has implications outside of the laboratory via a relationship with executive function, and, to a weaker extent, reading comprehension.


Assuntos
Sucesso Acadêmico , Ritmo alfa/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Córtex Cerebral/fisiopatologia , Potenciais Evocados/fisiologia , Função Executiva/fisiologia , Memória de Curto Prazo/fisiologia , Memória Espacial/fisiologia , Adolescente , Criança , Compreensão/fisiologia , Feminino , Humanos , Masculino , Leitura
7.
Eur Child Adolesc Psychiatry ; 28(3): 293-305, 2019 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29445867

RESUMO

Neurofeedback (NF) has gained increasing interest in the treatment of attention-deficit/hyperactivity disorder (ADHD). Given learning principles underlie NF, lasting clinical treatment effects may be expected. This systematic review and meta-analysis addresses the sustainability of neurofeedback and control treatment effects by considering randomized controlled studies that conducted follow-up (FU; 2-12 months) assessments among children with ADHD. PubMed and Scopus databases were searched through November 2017. Within-group and between-group standardized mean differences (SMD) of parent behavior ratings were calculated and analyzed. Ten studies met inclusion criteria (NF: ten studies, N = 256; control: nine studies, N = 250). Within-group NF effects on inattention were of medium effect size (ES) (SMD = 0.64) at post-treatment and increased to a large ES (SMD = 0.80) at FU. Regarding hyperactivity/impulsivity, NF ES were medium at post-treatment (SMD = 0.50) and FU (SMD = 0.61). Non-active control conditions yielded a small significant ES on inattention at post-treatment (SMD = 0.28) but no significant ES at FU. Active treatments (mainly methylphenidate), had large ES for inattention (post: SMD = 1.08; FU: SMD = 1.06) and medium ES for hyperactivity/impulsivity (post: SMD = 0.74; FU: SMD = 0.67). Between-group analyses also revealed an advantage of NF over non-active controls [inattention (post: SMD = 0.38; FU: SMD = 0.57); hyperactivity-impulsivity (post: SMD = 0.25; FU: SMD = 0.39)], and favored active controls for inattention only at pre-post (SMD = - 0.44). Compared to non-active control treatments, NF appears to have more durable treatment effects, for at least 6 months following treatment. More studies are needed for a properly powered comparison of follow-up effects between NF and active treatments and to further control for non-specific effects.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Neurorretroalimentação/métodos , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Criança , Feminino , Humanos , Masculino
8.
J Child Psychol Psychiatry ; 59(3): 223-231, 2018 03.
Artigo em Inglês | MEDLINE | ID: mdl-28921526

RESUMO

BACKGROUND: Attention-deficit/hyperactivity disorder (ADHD) is a heterogeneous condition for which multiple efforts to characterize brain state differences are underway. The objective of this study was to identify distinct subgroups of resting electroencephalography (EEG) profiles among children with and without ADHD and subsequently provide extensive clinical characterization of the subgroups. METHODS: Latent class analysis was used with resting state EEG recorded from a large sample of 781 children with and without ADHD (N = 620 ADHD, N = 161 Control), aged 6-18 years old. Behavioral and cognitive characteristics of the latent classes were derived from semistructured diagnostic interviews, parent completed behavior rating scales, and cognitive test performance. RESULTS: A five-class solution was the best fit for the data, of which four classes had a defining spectral power elevation. The distribution of ADHD and control subjects was similar across classes suggesting there is no one resting state EEG profile for children with or without ADHD. Specific latent classes demonstrated distinct behavioral and cognitive profiles. Those with elevated slow-wave activity (i.e. delta and theta band) had higher levels of externalizing behaviors and cognitive deficits. Latent subgroups with elevated alpha and beta power had higher levels of internalizing behaviors, emotion dysregulation, and intact cognitive functioning. CONCLUSIONS: There is population-level heterogeneity in resting state EEG subgroups, which are associated with distinct behavioral and cognitive profiles. EEG measures may be more useful biomarkers of ADHD outcome or treatment response rather than diagnosis.


Assuntos
Comportamento do Adolescente/fisiologia , Transtorno do Deficit de Atenção com Hiperatividade/classificação , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Sintomas Comportamentais/fisiopatologia , Ondas Encefálicas/fisiologia , Comportamento Infantil/fisiologia , Disfunção Cognitiva/fisiopatologia , Adolescente , Sintomas Afetivos/etiologia , Sintomas Afetivos/fisiopatologia , Transtorno do Deficit de Atenção com Hiperatividade/complicações , Transtorno do Deficit de Atenção com Hiperatividade/genética , Sintomas Comportamentais/etiologia , Criança , Disfunção Cognitiva/etiologia , Feminino , Humanos , Masculino
9.
J Clin Child Adolesc Psychol ; 47(5): 727-736, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-27431690

RESUMO

Although birth weight is a potential causal risk factor for attention-deficit/hyperactivity disorder (ADHD) symptoms, both the specificity of this association and its mediating pathways are largely unknown. We carefully assessed youth with and without ADHD (i.e., Wave 1), and followed them prospectively for 2 years (i.e., Wave 2). We (a) tested the association of birth weight with Wave 2 ADHD symptoms, and (b) evaluated biologically plausible neurocognitive functions from Wave 1 as temporally ordered mediators of birth weight and Wave 2 ADHD symptoms in a multiple mediation framework. At Wave 1, 222 ethnically diverse youth (30% female; ages 5-10) completed the Digit Span, Vocabulary, Symbol Search, and Arithmetic subtests of the Wechsler Intelligence Scale for Children-IV. At both Wave 1 and Wave 2 (ages 7-13), multiple informants (i.e., parents, teachers) rated youth ADHD symptoms and co-occurring psychopathology using multiple methods (i.e., structured interview, rating scale). Controlling for demographic factors, gestational age, and co-occurring externalizing and internalizing psychopathology, birth weight inversely predicted Wave 2 ADHD symptoms across multiple methods and informants. Additionally, controlling for Wave 1 ADHD symptoms and relevant covariates, Wave 1 Arithmetic uniquely mediated the association of birth weight with multi-method/informant Wave 2 ADHD symptoms. These findings suggest that birth weight is a relatively specific risk factor for youth ADHD symptoms and they implicate individual differences in fluid reasoning as a preliminary causal mediator of this association. We discuss implications for future research evaluating causal mechanisms underlying risk factors for ADHD.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Peso ao Nascer/fisiologia , Testes de Estado Mental e Demência , Transtornos Neurocognitivos/diagnóstico , Transtornos Neurocognitivos/psicologia , Adolescente , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Transtornos Neurocognitivos/fisiopatologia , Resolução de Problemas/fisiologia , Estudos Prospectivos , Estudos Retrospectivos , Adulto Jovem
10.
Child Psychiatry Hum Dev ; 49(5): 822-832, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29560540

RESUMO

Predictors of math achievement in attention-deficit/hyperactivity disorder (ADHD) are not well-known. To address this gap in the literature, we examined individual differences in neurocognitive functioning domains on math computation in a cross-sectional sample of youth with ADHD. Gender and anxiety symptoms were explored as potential moderators. The sample consisted of 281 youth (aged 8-15 years) diagnosed with ADHD. Neurocognitive tasks assessed auditory-verbal working memory, visuospatial working memory, and processing speed. Auditory-verbal working memory speed significantly predicted math computation. A three-way interaction revealed that at low levels of anxious perfectionism, slower processing speed predicted poorer math computation for boys compared to girls. These findings indicate the uniquely predictive values of auditory-verbal working memory and processing speed on math computation, and their differential moderation. These findings provide preliminary support that gender and anxious perfectionism may influence the relationship between neurocognitive functioning and academic achievement.


Assuntos
Ansiedade , Transtorno do Deficit de Atenção com Hiperatividade/psicologia , Matemática , Testes de Estado Mental e Demência , Perfeccionismo , Logro , Adolescente , Ansiedade/diagnóstico , Ansiedade/etiologia , Ansiedade/psicologia , Criança , Estudos Transversais , Feminino , Humanos , Masculino , Memória de Curto Prazo , Fatores Sexuais , Adulto Jovem
11.
Curr Opin Neurol ; 29(2): 137-47, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26910484

RESUMO

PURPOSE OF REVIEW: Many studies have reported that individuals with autism spectrum disorder (ASD) have different brain connectivity patterns compared with typically developing individuals. However, the results of more recent studies do not unanimously support the traditional view in which individuals with ASD have lower connectivity between distant brain regions and increased connectivity within local brain regions. In this review, we discuss different methods for measuring brain connectivity and how the use of different metrics may contribute to the lack of convergence of investigations of connectivity in ASD. RECENT FINDINGS: The discrepancy in brain connectivity results across studies may be due to important methodological factors, such as the connectivity measure applied, the age of patients studied, the brain region(s) examined, and the time interval and frequency band(s) in which connectivity was analyzed. SUMMARY: We conclude that more sophisticated electroencephalography analytic approaches should be utilized to more accurately infer causation and directionality of information transfer between brain regions, which may show dynamic changes of functional connectivity in the brain. Moreover, further investigations of connectivity with respect to behavior and clinical phenotype are needed to probe underlying brain networks implicated in core deficits of ASD.


Assuntos
Transtorno do Espectro Autista/fisiopatologia , Mapeamento Encefálico , Encéfalo/fisiopatologia , Vias Neurais/fisiopatologia , Transtorno do Espectro Autista/diagnóstico , Transtorno do Espectro Autista/patologia , Encéfalo/patologia , Humanos , Imageamento por Ressonância Magnética/métodos , Vias Neurais/patologia
12.
J Child Psychol Psychiatry ; 57(1): 4-17, 2016 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-26099166

RESUMO

BACKGROUND: Electroencephalography (EEG) and related measures have a long and productive history in child psychopathology research and are currently experiencing a renaissance in interest, particularly for use as putative biomarkers. METHOD AND SCOPE: First, the recent history leading to the use of EEG measures as endophenotypes and biomarkers for disease and treatment response are reviewed. Two key controversies within the area of noninvasive human electrophysiology research are discussed, and problems that currently either function as barriers or provide gateways to progress. First, the differences between the main types of EEG measurements (event-related potentials, quantitative EEG, and time-frequency measures) and how they can contribute collectively to better understanding of cortical dynamics underlying cognition and behavior are highlighted. Second, we focus on the ongoing shift in analytic focus to specific cortical sources and source networks whose dynamics are relevant to the clinical and experimental focus of the study, and the effective increase in source signal-to-noise ratio (SNR) that may be obtained in the process. CONCLUSIONS: Understanding of these issues informs any discussion of current trends in EEG research. We highlight possible ways to evolve our understanding of brain dynamics beyond the apparent contradictions in understanding and modeling EEG activity highlighted by these controversies. Finally, we summarize some promising future directions of EEG biomarker research in child psychopathology.

13.
J Child Psychol Psychiatry ; 57(5): 656-8, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-27090383

RESUMO

Recently several new tests have received US Federal Drug Administration (FDA) marketing approval as aids in the diagnostic process for attention deficit hyperactivity disorder (ADHD), including the Neuropsychiatric electroencephalogram (EEG)-Based ADHD Assessment Aid (NEBA) Health test. The NEBA test relies upon an EEG-based measure, called the theta to beta ratio (TBR). Although this measure has yielded large differences between ADHD and non-ADHD groups in studies prior to 2009, recent studies and a meta-analysis could not replicate these findings. In this article, we have used the NEBA device as an exemplar for a discussion that distinguishes between FDA de novo marketing approval for a device and any claims that that device is empirically supported, scientifically validated with replicated findings. It is understood that the aims of each differ; however, for many, including the lay public as well as some mental health professionals, these terms may be confused and treated as though they are synonymous. With regard to the TBR measure, there is no reliable association or replication for its clinical usage in the ADHD diagnostic process. The recommendation for potential consumers of the NEBA Health test (as well as perhaps for other existing FDA-approved diagnostic tests) is caveat emptor (let the buyer beware!).


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Aprovação de Equipamentos/normas , Eletroencefalografia/instrumentação , Psiquiatria Infantil/normas , Humanos , Psicologia da Criança/normas
14.
J Neurosci ; 34(4): 1171-82, 2014 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-24453310

RESUMO

In the current study we sought to dissociate the component processes of working memory (WM) (vigilance, encoding and maintenance) that may be differentially impaired in attention-deficit/ hyperactivity disorder (ADHD). We collected electroencephalographic (EEG) data from 52 children with ADHD and 47 typically developing (TD) children, ages 7-14 years, while they performed a spatial Sternberg working memory task. We used independent component analysis and time-frequency analysis to identify midoccipital alpha (8-12 Hz) to evaluate encoding processes and frontal midline theta (4-7 Hz) to evaluate maintenance processes. We tested for effects of task difficulty and cue processing to evaluate vigilance. Children with ADHD showed attenuated alpha band event-related desynchronization (ERD) during encoding. This effect was more pronounced when task difficulty was low (consistent with impaired vigilance) and was predictive of memory task performance and symptom severity. Correlated with alpha ERD during encoding were alpha power increases during the maintenance period (relative to baseline), suggesting a compensatory effort. Consistent with this interpretation, midfrontal theta power increases during maintenance were stronger in ADHD and in high-load memory conditions. Furthermore, children with ADHD exhibited a maturational lag in development of posterior alpha power whereas age-related changes in frontal theta power deviated from the TD pattern. Last, subjects with ADHD showed age-independent attenuation of evoked responses to warning cues, suggesting low vigilance. Combined, these three EEG measures predicted diagnosis with 70% accuracy. We conclude that the interplay of impaired vigilance and encoding in ADHD may compromise maintenance and lead to impaired WM performance in this group.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Memória de Curto Prazo/fisiologia , Adolescente , Nível de Alerta/fisiologia , Atenção/fisiologia , Criança , Eletroencefalografia , Feminino , Humanos , Masculino
15.
Curr Opin Neurol ; 28(2): 110-6, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25710286

RESUMO

PURPOSE OF REVIEW: The heterogeneity in clinical presentation and outcome in neurodevelopmental disorders such as attention deficit hyperactivity disorder (ADHD) autism spectrum disorder (ASD) necessitates the identification and validation of biomarkers that can guide diagnosis, predict developmental outcomes, and monitor treatment response. Electrophysiology holds both practical and theoretical advantages as a clinical biomarker in neurodevelopmental disorders, and considerable effort has been invested in the search for electroencephalography (EEG) biomarkers in ADHD and ASD. RECENT FINDINGS: Here, we discuss the major themes in the evaluation of biomarkers and then review studies that have applied EEG to better inform diagnosis, focusing on the controversy surrounding the theta:beta ratio in ADHD; prediction of risk, highlighting recent studies of infants at high risk for ASD; and treatment monitoring, presenting new efforts in the redefinition of outcome measures in clinical trials of ASD treatment. SUMMARY: We conclude that insights gained from EEG studies will contribute significantly to a more mechanistic understanding of these disorders and to the development of biomarkers that can assist with diagnosis, prognosis, and intervention. There is a need, however, to utilize approaches that accommodate, rather than ignore, diagnostic heterogeneity and individual differences.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtornos Globais do Desenvolvimento Infantil/diagnóstico , Transtornos Globais do Desenvolvimento Infantil/genética , Deficiências do Desenvolvimento/diagnóstico , Deficiências do Desenvolvimento/terapia , Eletroencefalografia , Animais , Transtorno do Deficit de Atenção com Hiperatividade/genética , Biomarcadores/análise , Deficiências do Desenvolvimento/genética , Eletroencefalografia/métodos , Humanos , Resultado do Tratamento
16.
J Clin Nurs ; 24(1-2): 57-68, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25258116

RESUMO

AIMS AND OBJECTIVES: To describe the process of implementing evidence-based practice in a clinical nursing setting. BACKGROUND: Evidence-based practice has become a major issue in nursing, it is insufficiently integrated into daily practice and its implementation is complex. DESIGN: Participatory action research. METHODS: The main participants were nurses working in a lung unit of a rural hospital. A multi-method process of data collection was used during the observing, reflecting, planning and acting phases. Data were continuously gathered during a 24-month period from 2010 to 2012, and analysed using an interpretive constant comparative approach. Patients were consulted to incorporate their perspective. RESULTS: A best-practice mode of working was prevalent on the ward. The main barriers to the implementation of evidence-based practice were that nurses had little knowledge of evidence-based practice and a rather negative attitude towards it, and that their English reading proficiency was poor. The main facilitators were that nurses wanted to deliver high-quality care and were enthusiastic and open to innovation. Implementation strategies included a tailored interactive outreach training and the development and implementation of an evidence-based discharge protocol. The academic model of evidence-based practice was adapted. Nurses worked according to the evidence-based practice discharge protocol but barely recorded their activities. Nurses favourably evaluated the participatory action research process. CONCLUSIONS: Action research provides an opportunity to empower nurses and to tailor evidence-based practice to the practice context. Applying and implementing evidence-based practice is difficult for front-line nurses with limited evidence-based practice competencies. RELEVANCE TO CLINICAL PRACTICE: Adaptation of the academic model of evidence-based practice to a more pragmatic approach seems necessary to introduce evidence-based practice into clinical practice. The use of scientific evidence can be facilitated by using pre-appraised evidence. For clinical practice, it seems relevant to integrate scientific evidence with clinical expertise and patient values in nurses' clinical decision-making at the individual patient level.


Assuntos
Pesquisa em Enfermagem Clínica , Enfermagem Baseada em Evidências , Pesquisa sobre Serviços de Saúde , Adulto , Atitude do Pessoal de Saúde , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Projetos de Pesquisa
17.
Curr Psychiatry Rep ; 16(11): 498, 2014 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-25234074

RESUMO

Electroencephalography (EEG) has, historically, played a focal role in the assessment of neural function in children with attention deficit hyperactivity disorder (ADHD). We review here the most recent developments in the utility of EEG in the diagnosis of ADHD, with emphasis on the most commonly used and emerging EEG metrics and their reliability in diagnostic classification. Considering the clinical heterogeneity of ADHD and the complexity of information available from the EEG signals, we suggest that considerable benefits are to be gained from multivariate analyses and a focus towards understanding of the neural generators of EEG. We conclude that while EEG cannot currently be used as a diagnostic tool, vast developments in analytical and technological tools in its domain anticipate future progress in its utility in the clinical setting.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Eletroencefalografia/normas , Potenciais Evocados/fisiologia , Eletroencefalografia/métodos , Humanos
18.
J Atten Disord ; : 10870547241253999, 2024 May 26.
Artigo em Inglês | MEDLINE | ID: mdl-38798087

RESUMO

OBJECTIVE: ADHD is a prevalent neurodevelopmental disorder characterized by symptoms of inattention and hyperactivity-impulsivity. Impairments in executive functioning (EF) are central to models of ADHD, while alpha-band spectral power event-related decreases (ERD) have emerged as a putative electroencephalography (EEG) biomarker of EF in ADHD. Little is known about the roles of EF and alpha ERD and their interactions with symptoms of ADHD. METHOD: We estimated network models of ADHD symptoms and integrated alpha ERD measures into the symptom network. RESULTS: EF emerges as a bridge network node connecting alpha ERD and the hyperactivity/impulsivity and inattention symptoms. We found that EF most closely relates to a subset of symptoms, namely the motoric symptoms, "seat" (difficulty staying seated), and "runs" (running or climbing excessively). CONCLUSIONS: EF functions as a bridge node connecting alpha ERD and the ADHD symptom network. Motoric-type symptoms and EF deficits may constitute important nodes in the interplay between behavior/symptoms, cognition, and neurophysiological markers of ADHD.

19.
Behav Brain Res ; 469: 115003, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38642862

RESUMO

BACKGROUND: Executive functioning deficits are central to established neuropsychological models of ADHD. Oscillatory activity, particularly the alpha rhythm (8-12 Hz) has been associated with cognitive impairments in ADHD. However, most studies to date examined such neural mechanisms underlying executive dysfunction in children and adolescents with ADHD, raising the question of whether and to what extent those ADHD-related working memory impairments are still present in adults. To this end, the current study aimed to investigate the role of alpha event-related decreases (ERD) during working memory processes in adults with and without ADHD. METHODS: We collected electroencephalographic (EEG) data from 85 adults with a lifetime diagnosis of ADHD and 105 controls (aged 32-64), while they performed a continuous performance (CPT) and a spatial delayed response working memory task (SDRT). Time-frequency and independent component analysis (ICA) was used to identify alpha (8-12 Hz) clusters to examine group and condition effects during the temporal profile of sustained attention and working memory processes (encoding, maintenance, retrieval), loads (low and high) and trial type (go and nogo). RESULTS: Individuals with ADHD exhibited higher reaction time-variability in SDRT, and slower response times in SDRT and CPT, despite no differences in task accuracy. Although working memory load was associated with stronger alpha ERD in both tasks and both groups (ADHD, controls), we found no consistent evidence for attenuated alpha ERD in adults with ADHD, failing to replicate effects reported in children. In contrast, when looking at the whole sample, the correlations of alpha power during encoding with inattention and hyperactivity-impulsivity symptoms were significant, replicating prior findings in children with ADHD, but suggesting an alternate source for these effects in adults. CONCLUSIONS: Our results corroborate the robustness of alpha as a marker of visual attention and suggest that occipital alpha ERD normalizes in adulthood, but with unique contributions of centro-occipital alpha ERD, suggesting a secondary source. This implies that deviations in processes other than previously reported visuospatial cortex engagement may account for the persistent symptoms and cognitive deficits in adults with a history of ADHD.


Assuntos
Ritmo alfa , Transtorno do Deficit de Atenção com Hiperatividade , Atenção , Memória de Curto Prazo , Humanos , Transtorno do Deficit de Atenção com Hiperatividade/fisiopatologia , Memória de Curto Prazo/fisiologia , Masculino , Feminino , Adulto , Ritmo alfa/fisiologia , Atenção/fisiologia , Pessoa de Meia-Idade , Tempo de Reação/fisiologia , Eletroencefalografia , Função Executiva/fisiologia , Testes Neuropsicológicos , Desempenho Psicomotor/fisiologia
20.
J Child Adolesc Psychopharmacol ; 34(4): 167-182, 2024 05.
Artigo em Inglês | MEDLINE | ID: mdl-38686563

RESUMO

Objectives: This review aims to present recent innovations and advancements in attention-deficit/hyperactivity disorder (ADHD) care, encompassing international consensus statement, new medication formulations, digital therapeutics, and neurostimulation devices. Methods: A comprehensive literature search of relevant articles published in the past five years was conducted, emphasizing the evidence base, efficacy, safety, and practical implications of these advancements. Results: The World Federation of ADHD Consensus Statement offers an updated diagnostic and treatment framework rooted in global scientific evidence. There are several newer ADHD medication formulations, including a nonstimulant (Viloxazine extended release) and the first transdermal amphetamine patch approved to treat ADHD. These options offer some unique benefits to personalize treatment based on symptom profile, lifestyle, preferences, and response. Digital tools offer additional means to restructure environments for individuals with ADHD, reducing impairment and reliance on others. In addition, digital therapeutics enhance access, affordability, personalization, and feasibility of ADHD care, complementing or augmenting existing interventions. Trigeminal nerve stimulation emerges as a well-tolerated nonpharmacological, device-based treatment for pediatric ADHD, with initial trials indicating effect sizes comparable to nonstimulant medications. Conclusions: These innovations in ADHD care represent clinically significant new treatment options and opportunities for personalized care. Health care professionals should integrate these developments into clinical practice, mindful of individual patient and family needs and preferences. Future research should assess long-term outcomes, cost-effectiveness, and acceptability of these innovations.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Estimulantes do Sistema Nervoso Central , Transtorno do Deficit de Atenção com Hiperatividade/tratamento farmacológico , Humanos , Estimulantes do Sistema Nervoso Central/uso terapêutico , Estimulantes do Sistema Nervoso Central/administração & dosagem , Consenso , Criança , Terapia por Estimulação Elétrica/métodos
SELEÇÃO DE REFERÊNCIAS
Detalhe da pesquisa