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1.
Child Dev ; 90(5): 1718-1737, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-29484637

RESUMO

Despite a robust literature examining the association between sleep problems and cognitive abilities in childhood, little is known about this association in toddlerhood, a period of rapid cognitive development. The present study examined the association between various sleep problems, using actigraphy, and performance on a standardized test of cognitive abilities, longitudinally across three ages (30, 36, and 42 months) in a large sample of toddlers (N = 493). Results revealed a between-subject effect in which the children who had more delayed sleep schedules on average also showed poorer cognitive abilities on average but did not support a within-subjects effect. Results also showed that delayed sleep explains part of the association between family socioeconomic context and child cognitive abilities.


Assuntos
Aptidão/fisiologia , Desenvolvimento Infantil/fisiologia , Cognição/fisiologia , Família , Sono/fisiologia , Fatores Socioeconômicos , Actigrafia , Pré-Escolar , Feminino , Humanos , Estudos Longitudinais , Masculino , Fatores de Tempo
2.
Clin J Sport Med ; 29(4): 292-297, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31241531

RESUMO

OBJECTIVE: To examine whether oculomotor and electrophysiological measures improve the clinical performance of the typical concussion protocol for classifying collegiate athletes with a history of concussion. DESIGN: Cross-sectional. SETTING: University Athletic Medicine and Research Facility. PARTICIPANTS: Forty-five varsity collegiate athletes. INDEPENDENT VARIABLES: Collegiate varsity athletes with or without a history of a diagnosed concussion. MAIN OUTCOME MEASURES: Multivariate receiver operating curve and area under the curve (AUC) analyses tested the clinical performance of the typical concussion protocol (symptoms, postural control, neuropsychological abilities). We examined differences in clinical performance between this protocol and after adding reflexive saccade and event-related potential (ERP) indices. Hypotheses were formed after data collection. RESULTS: Significant AUCs were demonstrated for the typical concussion protocol (model 1: AUC = 0.75, P = 0.007), after adding reflexive saccade eye excursion gain (model 2: AUC = 0.80, P = 0.001), and ERPs (model 3: AUC = 0.79, P = 0.002). The AUC for reflexive saccades and ERPs was significant (model 4: AUC = 0.70, P = 0.030). Model 2's increased clinical performance compared with model 1 was nonsignificant, χ(2) = 1.871, P = 0.171. CONCLUSIONS: All 4 models demonstrated adequate sensitivity and specificity for classifying athletes with a previous concussion. Adding reflexive saccades and ERPs did not significantly increase clinical performance of the typical concussion protocol. Future research should determine the clinical utility of saccades and ERPs for acute postconcussion assessments.


Assuntos
Traumatismos em Atletas/diagnóstico , Concussão Encefálica/diagnóstico , Potenciais Evocados , Movimentos Sacádicos , Adolescente , Área Sob a Curva , Atletas , Estudos Transversais , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Equilíbrio Postural , Sensibilidade e Especificidade , Adulto Jovem
3.
J Child Psychol Psychiatry ; 59(10): 1044-1051, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-30255499

RESUMO

BACKGROUND: Externalizing problems, including aggression and conduct problems, are thought to involve impaired attentional capacities. Previous research suggests that the P3 event-related potential (ERP) component is an index of attentional processing, and diminished P3 amplitudes to infrequent stimuli have been shown to be associated with externalizing problems and attention-deficit/hyperactivity disorder (ADHD). However, the vast majority of this prior work has been cross-sectional and has not examined young children. The present study is the first investigation of whether within-individual changes in P3 amplitude predict changes in externalizing problems, providing a stronger test of developmental process. METHOD: Participants included a community sample of children (N = 153) followed longitudinally at 30, 36, and 42 months of age. Children completed an oddball task while ERP data were recorded. Parents rated their children's aggression and ADHD symptoms. RESULTS: Children's within-individual changes in the P3 amplitude predicted concomitant within-child changes in their aggression such that smaller P3 amplitudes (relative to a child's own mean) were associated with more aggression symptoms. However, changes in P3 amplitudes were not significantly associated with ADHD symptoms. CONCLUSIONS: Findings suggest that the P3 may play a role in development of aggression, but do not support the notion that the P3 plays a role in development of early ADHD symptoms.


Assuntos
Transtornos do Comportamento Infantil/fisiopatologia , Potenciais Evocados P300/fisiologia , Pré-Escolar , Eletroencefalografia/estatística & dados numéricos , Feminino , Humanos , Estudos Longitudinais , Masculino
4.
J Pediatr Psychol ; 39(6): 624-32, 2014 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-24781412

RESUMO

OBJECTIVE: To develop and evaluate adjustment factors to convert parent-reported time in bed to an estimate of child sleep time consistent with objective measurement. METHODS: A community sample of 217 children aged 4-9 years (mean age = 6.6 years) wore actigraph wristwatches to objectively measure sleep for 7 days while parents completed reports of child sleep each night. After examining the moderators of the discrepancy between parent reports and actigraphy, 3 adjustment factors were evaluated. RESULTS: Parent report of child sleep overestimated nightly sleep duration by ∼24 min per night relative to actigraphy. Child age, gender, and sleep quality all had small or nonsignificant associations with correspondence between parent report and actigraph. Empirically derived adjustment factors significantly reduced the discrepancy between parent report and objective measurement. CONCLUSIONS: Simple adjustment factors can enhance the correspondence and utility of parent reports of child sleep duration for clinical and research purposes.


Assuntos
Actigrafia , Sono/fisiologia , Fatores Etários , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Fatores Sexuais
5.
J Sleep Res ; 20(1 Pt 2): 223-32, 2011 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-20629939

RESUMO

Actigraphic (ACT) recordings are used widely in schoolchildren as a less intrusive and more extended approach to evaluation of sleep problems. However, critical assessment of the validity and reliability of ACT against overnight polysomnography (NPSG) are unavailable. Thus, we explored the degree of concordance between NPSG and ACT in school-aged children to delineate potential ACT boundaries when interpreting pediatric sleep. Non-dominant wrist ACT was recorded simultaneously with NPSG in 149 healthy school-aged children (aged 4.1-8.8 years, 41.7% boys, 80.4% Caucasian) recruited from the community. Analyses were limited to the Actiware (MiniMitter-64) calculated parameters originating from 1-min epoch sampling and medium sensitivity threshold value of 40; i.e. sleep period time (SPT), total sleep time (TST) and wake after sleep onset (WASO). SPT was not significantly different between ACT and NPSG. However, ACT underestimated TST significantly by 32.2±33.4 min and overestimated WASO by 26.3±34.4 min. The decreased precision of ACT was also evident from moderate to small concordance correlation coefficients (0.47 for TST and 0.09 for WASO). ACT in school-aged children provides reliable assessment of sleep quantity, but is relatively inaccurate during determination of sleep quality. Thus, caution is advocated in drawing definitive conclusions from ACT during evaluation of the sleep-disturbed child.


Assuntos
Actigrafia , Polissonografia , Sono/fisiologia , Criança , Feminino , Humanos , Masculino , Fatores de Tempo , Vigília/fisiologia
6.
Neurotrauma Rep ; 2(1): 626-638, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-35018364

RESUMO

Cases of concussions in the United States keep increasing and are now up to 2 million to 3 million incidents per year. Although concussions are recoverable and usually not life-threatening, the degree and rate of recovery may vary depending on age, severity of the injury, and past concussion history. A subsequent concussion before full recovery may lead to more-severe brain damage and poorer outcomes. Electroencephalography (EEG) recordings can identify brain dysfunctionality and abnormalities, such as after a concussion. Routine EEG monitoring can be a convenient method for reducing unreported injuries and preventing long-term damage, especially among groups with a greater risk of experiencing a concussion, such as athletes participating in contact sports. Because of the relative availability of EEG compared to other brain-imaging techniques (e.g., functional magnetic resonance imaging), the use of EEG monitoring is growing for various neurological disorders. In this longitudinal study, EEG was analyzed from 4 football athletes before their athletic season and also within 7 days of concussion. Compared to a control group of 4 additional athletes, a concussion was detected with up to 99.5% accuracy using EEG recordings in the Theta-Alpha band. Classifiers that use data from only a subset of the EEG electrodes providing reliable detection are also proposed. The most effective classifiers used EEG recordings from the Central scalp region in the Beta band and over the Temporal scalp region using the Theta-Alpha band. This proof-of-concept study and preliminary findings suggest that EEG monitoring may be used to identify a sports-related concussion occurrence with a high level of accuracy and thus reduce the chance of unreported concussion.

7.
Dev Psychol ; 57(11): 1755-1771, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34914443

RESUMO

Inhibitory control has been widely studied in association with social and academic adjustment. However, prior studies have generally overlooked the potential heterotypic continuity of inhibitory control and how this could affect assessment and understanding of its development. In the present study, we systematically considered heterotypic continuity in four well-established measures of inhibitory control, testing two competing hypotheses: (a) the manifestation of inhibitory control coheres within and across time in consistent, relatively simple ways, consistent with homotypic continuity. Alternatively, (b) with developmental growth, inhibitory control manifests in more complex ways with changes across development, consistent with heterotypic continuity. We also explored differences in inhibitory control as a function of the child's sex, language ability, and the family's socioeconomic status. Children (N = 513) were studied longitudinally at 30, 36, and 42 months of age. Changes in the patterns of associations within and among inhibitory control measures across ages suggest that the measures' meanings change with age, the construct manifests differently across development, and, therefore, that the construct shows heterotypic continuity. We argue that the heterotypic continuity of inhibitory control motivates the use of different combinations of inhibitory control indexes at different points in development in future research to improve validity. Confirmatory factors and growth curves also suggest that individual differences in inhibitory control endure, with convergence among inhibitory control measures by 36 months of age. (PsycInfo Database Record (c) 2021 APA, all rights reserved).


Assuntos
Classe Social , Criança , Pré-Escolar , Humanos
8.
Brain Cogn ; 71(3): 369-74, 2009 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-19616356

RESUMO

Maternal stress and anxiety during pregnancy are related to negative developmental outcomes for offspring, both physiological and psychological, from the fetal period through early adolescence. This robust relationship is likely to be partly explained by alterations in fetal neurodevelopmental programming, calling for further examination of neurophysiologically-based cognitive markers that may be related to the altered structure-function relationships that contribute to these negative developmental outcomes. The current investigation examined the relationship between perinatal maternal anxiety and neonatal auditory evoked responses (AERs) to mother and stranger voices. Results indicated that neonates of low-anxiety mothers displayed more negative frontal slow wave amplitudes in response to their mother's voice compared to a female stranger's voice, while neonates of high-anxiety mothers showed the opposite pattern. These findings suggest that neonates of perinatally anxious mothers may demonstrate neurophysiologically-based differences in attentional allocation. This could represent one pathway to the negative psychological outcomes seen throughout development in offspring of anxious mothers.


Assuntos
Ansiedade , Encéfalo/fisiologia , Potenciais Evocados Auditivos/fisiologia , Efeitos Tardios da Exposição Pré-Natal , Reconhecimento Psicológico/fisiologia , Estimulação Acústica , Análise de Variância , Percepção Auditiva/fisiologia , Eletroencefalografia , Feminino , Humanos , Recém-Nascido , Relações Mãe-Filho , Mães , Inventário de Personalidade , Gravidez , Percepção da Fala/fisiologia , Estresse Psicológico , Voz
9.
Brain Lang ; 199: 104695, 2019 12.
Artigo em Inglês | MEDLINE | ID: mdl-31610478

RESUMO

Newborns habituate to repeated auditory stimuli, and discriminate syllables, generating opportunities for early language learning. This study investigated trial-by-trial changes in newborn electrophysiological responses to auditory speech syllables as an index of habituation and novelty detection. Auditory event-related potentials (ERPs) were recorded from 16 term newborn infants, aged 1-3 days, in response to monosyllabic speech syllables presented during habituation and novelty detection tasks. Multilevel models demonstrated that newborns habituated to repeated auditory syllables, as ERP amplitude attenuated for a late-latency component over successive trials. Subsequently, during the novelty detection task, early- and late-latency component amplitudes decreased over successive trials for novel syllables only, indicating encoding of the novel speech syllable. We conclude that newborns dynamically encoded novel syllables over relatively short time periods, as indicated by a systematic change in response patterns with increased exposure. These results have important implications for understanding early precursors of learning and memory in newborns.


Assuntos
Potenciais Evocados Auditivos , Habituação Psicofisiológica , Desenvolvimento da Linguagem , Percepção da Fala , Feminino , Humanos , Recém-Nascido , Masculino , Memória , Fonética
10.
J Neurotrauma ; 36(8): 1343-1351, 2019 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-30343622

RESUMO

This prospective controlled observational cohort study assessed the performance of a novel panel of serum microRNA (miRNA) biomarkers on indicators of concussion, subconcussive impacts, and neurocognitive function in collegiate football players over the playing season. Male collegiate student football athletes participating in a Division I Football Bowl Subdivision of the National Collegiate Athletic Association (NCAA) were enrolled. There were a total of 53 participants included in the study, 30 non-athlete control subjects and 23 male collegiate student football athletes. Neurocognitive assessments and blood samples were taken within the week before the athletic season began and within the week after the last game of the season and measured for a panel of pre-selected miRNA biomarkers. All the athletes had elevated levels of circulating miRNAs at the beginning of the season compared with control subjects (p < 0.001). Athletes with the lowest standard assessment of concussion (SAC) scores at the beginning of the season had the highest levels of miRNAs. The area under the curve (AUC) for predicting pre-season SAC scores were miR-195 (0.90), miR-20a (0.89), miR-151-5p (0.86), miR-505* (0.85), miR-9-3p (0.77), and miR-362-3p (0.76). In athletes with declining neurocognitive function over the season, concentrations of miRNAs increased over same period. There were significant negative correlations with miR-505* (p = 0.011), miR-30d (p = 0.007), miR-92 (p = 0.033), and (p = 0.008). The miRNAs correlating with balance problems were miR-505* (p = 0.007), miR-30d (p = 0.028), and miR-151-5p (p = 0.023). Those correlating with poor reaction times were miR-20a (0.043), miR-505* (p = 0.049), miR-30d (p = 0.031), miR-92 (p = 0.015), and miR-151-5p (p = 0.044). Select miRNAs were associated with baseline concussion assessments at the beginning of the season and with neurocognitive changes from pre to post-season in collegiate football players. Should these findings be replicated in a larger cohort of athletes, these markers could potentially serve as measures of neurocognitive status in athletes at risk for concussion and subconcussive injuries.


Assuntos
Biomarcadores/sangue , Concussão Encefálica/sangue , Futebol Americano/lesões , RNA Mensageiro/sangue , Atletas , Estudos de Coortes , Humanos , Masculino , Estudos Prospectivos , Recuperação de Função Fisiológica/fisiologia , Adulto Jovem
11.
Int J Psychophysiol ; 132(Pt A): 135-144, 2018 10.
Artigo em Inglês | MEDLINE | ID: mdl-29024682

RESUMO

Sports-related concussions occur in approximately 21% of college athletes with implications for long-term cognitive impairments in working memory. Working memory involves the capacity to maintain short-term information and integrate with higher-order cognitive processing for planning and behavior execution, critical skills for optimal cognitive and athletic performance. This study quantified working memory impairments in 36 American football college athletes (18-23years old) using event-related potentials (ERPs). Despite performing similarly in a standard 2-back working memory task, athletes with history of concussion exhibited larger P1 and P3 amplitudes compared to Controls. Concussion History group latencies were slower for the P1 and faster for the N2. Source estimation analyses indicated that previously concussed athletes engaged different brain regions compared to athletes with no concussion history. These findings suggest that ERPs may be a sensitive and objective measure to detect long-term cognitive consequences of concussion.


Assuntos
Atletas , Traumatismos em Atletas/fisiopatologia , Concussão Encefálica/fisiopatologia , Córtex Cerebral/fisiopatologia , Disfunção Cognitiva/fisiopatologia , Potenciais Evocados/fisiologia , Futebol Americano/lesões , Memória de Curto Prazo/fisiologia , Adolescente , Adulto , Traumatismos em Atletas/complicações , Concussão Encefálica/complicações , Disfunção Cognitiva/etiologia , Eletroencefalografia , Humanos , Masculino , Estudantes , Universidades , Adulto Jovem
12.
Artigo em Inglês | MEDLINE | ID: mdl-29483345

RESUMO

The current study examined the association between effortful control and a well-studied neural index of self-regulation, the N2 event-related potential (ERP) component, in toddlers. Participants included 107 toddlers (44 girls) assessed at 30, 36 and 42 months of age. Participants completed a Go/NoGo task while electroencephalography data were recorded. The study focused on the N2 ERP component. Parent-reported effortful control was examined in association with the NoGo N2 ERP component. Findings suggest a positive association between the NoGo N2 component and the inhibitory control subscale of the wider effortful control dimension, suggesting that the N2 component may index processes associated with temperamental effortful control.This article is part of the theme issue 'Diverse perspectives on diversity: multi-disciplinary approaches to taxonomies of individual differences'.


Assuntos
Potenciais Evocados/fisiologia , Giro do Cíngulo/fisiologia , Inibição Psicológica , Rede Nervosa/fisiologia , Córtex Pré-Frontal/fisiologia , Temperamento/fisiologia , Mapeamento Encefálico , Pré-Escolar , Eletroencefalografia , Feminino , Giro do Cíngulo/anatomia & histologia , Humanos , Masculino , Rede Nervosa/anatomia & histologia , Testes Neuropsicológicos , Córtex Pré-Frontal/anatomia & histologia , Tempo de Reação
13.
Environ Health Perspect ; 115(4): 623-9, 2007 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-17450234

RESUMO

BACKGROUND: Tobacco smoking during pregnancy is known to adversely affect development of the central nervous system in babies of smoking mothers by restricting utero-placental blood flow and the amount of oxygen available to the fetus. Behavioral data associate maternal smoking with lower verbal scores and poorer performance on specific language/auditory tests. OBJECTIVES: In the current study we examined the effects of maternal smoking during pregnancy on newborns' speech processing ability as measured by event-related potentials (ERPs). METHOD: High-density ERPs were recorded within 48 hr of birth in healthy newborn infants of smoking (n = 8) and nonsmoking (n = 8) mothers. Participating infants were matched on sex, gestational age, birth weight, Apgar scores, mother's education, and family income. Smoking during pregnancy was determined by parental self-report and medical records. ERPs were recorded in response to six consonant-vowel syllables presented in random order with equal probability. RESULTS: Brainwaves of babies of nonsmoking mothers were characterized by typical hemisphere asymmetries, with larger amplitudes over the left hemisphere, especially over temporal regions. Further, infants of nonsmokers discriminated among a greater number of syllables whereas the newborns of smokers began the discrimination process at least 150 msec later and differentiated among fewer stimuli. CONCLUSIONS: Our findings indicate that prenatal exposure to tobacco smoke in otherwise healthy babies is linked with significant changes in brain physiology associated with basic perceptual skills that could place the infant at risk for later developmental problems.


Assuntos
Efeitos Tardios da Exposição Pré-Natal , Fumar/efeitos adversos , Percepção da Fala , Adulto , Encéfalo/fisiologia , Desenvolvimento Infantil , Potenciais Evocados , Feminino , Lateralidade Funcional , Humanos , Recém-Nascido , Masculino , Análise por Pareamento , Gravidez
14.
Int J Psychophysiol ; 112: 52-63, 2017 02.
Artigo em Inglês | MEDLINE | ID: mdl-27993611

RESUMO

Theory and research indicate considerable influence of socio-emotionally significant experiences on children's functioning and adaptation. In the current study, we examined neurophysiological correlates of children's allocation of information processing resources to socio-emotionally significant events, specifically, simulated marital interactions. We presented 9- to 11-year-old children (n=24; 11 females) with 15 videos of interactions between two actors posing as a married couple. Task-irrelevant brief auditory probes were presented during the videos, and event-related potentials (ERPs) elicited to the auditory probes were measured. As hypothesized, exposure to higher levels of interparental conflict was associated with smaller P1, P2, and N2 ERPs to the probes. This finding is consistent with the idea that children who had been exposed to more interparental conflict attended more to the videos and diverted fewer cognitive resources to processing the probes, thereby producing smaller ERPs to the probes. In addition, smaller N2s were associated with more child behavior problems, suggesting that allocating fewer processing resources to the probes was associated with more problem behavior. Results are discussed in terms of implications of socio-emotionally significant experiences for children's processing of interpersonal interactions.


Assuntos
Conflito Psicológico , Ajustamento Emocional/fisiologia , Potenciais Evocados/fisiologia , Relações Familiares/psicologia , Pais/psicologia , Criança , Eletroencefalografia , Potenciais Evocados Auditivos/fisiologia , Feminino , Humanos , Masculino
15.
Dev Neuropsychol ; 29(2): 379-95, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16515411

RESUMO

This study investigated learning-related changes in the brain activity of young adults. A group of 29 undergraduate students (18-24 years) participated in a learning study that included a pretest, a training session, and a posttest. Each trial involved presentation of a complex visual stimulus and its spoken "name." Auditory event-related potentials (ERPs) were recorded in response to matching and mismatching names. In the pretest, the participants guessed whether the names were matching the figures. During training they learned the names of a set of simple elements making up the complex figures and were required to master a simple rule for combining the visual and auditory stimuli. The posttest included presentation of the combinations learned during training as well as novel pairings of the same elements. Following training the number of correct responses for learned items doubled and the amplitudes of the auditory ERPs to learned and rule transfer stimuli were more positive than brain waves to the not learned or novel items over most of the analysis window. The ERPs further differentiated between a familiarity response (late positive shift) and learning-specific changes (N2-P3 range). Overall, the findings suggest that ERPs can be a useful tool for learning assessment and offer new insights in the study of individual differences associated with the learning process.


Assuntos
Mapeamento Encefálico , Córtex Cerebral/fisiologia , Potenciais Evocados Auditivos/fisiologia , Potenciais Evocados Visuais/fisiologia , Aprendizagem/fisiologia , Estimulação Acústica/métodos , Adolescente , Adulto , Análise de Variância , Eletroencefalografia/métodos , Feminino , Lateralidade Funcional/fisiologia , Humanos , Masculino , Estimulação Luminosa/métodos
16.
J Learn Disabil ; 39(4): 352-63, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16895159

RESUMO

Event-related potentials (ERPs) were recorded from 27 children (14 girls, 13 boys) who varied in their reading skill levels. Both behavior performance measures recorded during the ERP word classification task and the ERP responses themselves discriminated between children with above-average, average, and below-average reading skills. ERP amplitudes and peak latencies decreased as reading skills increased. Furthermore, hemisphere differences increased with higher reading skill levels. Sex differences were also related to ERP amplitude variations across the scalp. However, ERPs recorded from boys and girls did not differ as a function of differences in the children's reading levels.


Assuntos
Aptidão , Encéfalo/anatomia & histologia , Leitura , Encéfalo/fisiologia , Criança , Potenciais Evocados/fisiologia , Feminino , Humanos , Masculino
17.
J Neurotrauma ; 33(23): 2081-2090, 2016 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-27025905

RESUMO

This study investigated the effects of a past concussion on electrophysiological indices of attention in college athletes. Forty-four varsity football athletes (22 with at least one past concussion) participated in three neuropsychological tests and a two-tone auditory oddball task while undergoing high-density event-related potential (ERP) recording. Athletes previously diagnosed with a concussion experienced their most recent injury approximately 4 years before testing. Previously concussed and control athletes performed equivalently on three neuropsychological tests. Behavioral accuracy and reaction times on the oddball task were also equivalent across groups. However, athletes with a concussion history exhibited significantly larger N2 and P3b amplitudes and longer P3b latencies. Source localization using standardized low-resolution brain electromagnetic tomography indicated that athletes with a history of concussion generated larger electrical current density in the left inferior parietal gyrus compared to control athletes. These findings support the hypothesis that individuals with a past concussion recruit compensatory neural resources in order to meet executive functioning demands. High-density ERP measures combined with source localization provide an important method to detect long-term neural consequences of concussion in the absence of impaired neuropsychological performance.


Assuntos
Atletas , Atenção/fisiologia , Concussão Encefálica/fisiopatologia , Eletroencefalografia/tendências , Potenciais Evocados/fisiologia , Futebol Americano/lesões , Adolescente , Atletas/psicologia , Traumatismos em Atletas/diagnóstico por imagem , Traumatismos em Atletas/fisiopatologia , Traumatismos em Atletas/psicologia , Concussão Encefálica/diagnóstico por imagem , Concussão Encefálica/psicologia , Radiação Eletromagnética , Futebol Americano/fisiologia , Futebol Americano/psicologia , Humanos , Imageamento por Ressonância Magnética/métodos , Masculino , Testes Neuropsicológicos , Tomografia/métodos , Universidades , Adulto Jovem
18.
IEEE Trans Biomed Eng ; 52(11): 1869-81, 2005 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-16285391

RESUMO

This paper introduces parametric multichannel fusion models to exploit the different but complementary brain activity information recorded from multiple channels in order to accurately classify differential brain activity into their respective categories. A parametric weighted decision fusion model and two parametric weighted data fusion models are introduced for the classification of averaged multichannel evoked potentials (EPs). The decision fusion model combines the independent decisions of each channel classifier into a decision fusion vector and a parametric classifier is designed to determine the EP class from the discrete decision fusion vector. The data fusion models include the weighted EP-sum model in which the fusion vector is a linear combination of the multichannel EPs and the EP-concatenation model in which the fusion vector is a vector-concatenation of the multichannel EPs. The discrete Karhunen-Loeve transform (DKLT) is used to select features for each channel classifier and from each data fusion vector. The difficulty in estimating the probability density function (PDF) parameters from a small number of averaged EPs is identified and the class conditional PDFs of the feature vectors of averaged EPs are, therefore, derived in terms of the PDFs of the single-trial EPs. Multivariate parametric classifiers are developed for each fusion strategy and the performances of the different strategies are compared by classifying 14-channel EPs collected from five subjects involved in making explicit match/mismatch comparisons between sequentially presented stimuli. It is shown that the performance improves by incorporating weights in the fusion rules and that the best performance is obtained using multichannel EP concatenation. It is also noted that the fusion strategies introduced are also applicable to other problems involving the classification of multicategory multivariate signals generated from multiple sources.


Assuntos
Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Diagnóstico por Computador/métodos , Eletroencefalografia/métodos , Potenciais Evocados/fisiologia , Modelos Neurológicos , Reconhecimento Automatizado de Padrão/métodos , Potenciais de Ação/fisiologia , Algoritmos , Humanos
19.
Neurotoxicol Teratol ; 27(6): 797-813, 2005.
Artigo em Inglês | MEDLINE | ID: mdl-16111858

RESUMO

OBJECTIVE: Prenatal cocaine-exposure may interfere with the ontogeny of prefrontal cortical executive functions due to cocaine's effect on the developing monoaminergic system. This study presents findings regarding cortical functioning in 29 prenatally cocaine-exposed (CE) and non-drug-exposed (NDE) 7- to 9-year-old children participating in event related potential (ERP) studies. METHODS: ERPs were recorded using 128-electrode high-density arrays while children responded to a standard Stroop paradigm. RESULTS: In the Stroop paradigm, CE children generated prolonged responses to the words while the NDE children produced briefer responses. Effects were noted in the region of the initial positive peak (P1), the second negative peak (N2) and the later positive peak (P3). CONCLUSIONS: Early cocaine exposure may inhibit the specialization and streamlining of brain region involvement during cognitive processing such that task processing is slower to begin, requires more diverse cortical involvement, and requires more time to complete. ERP methodology has considerable potential for studying frontal maturation and may provide additional information to clarify generally the specific effects of prenatal CE on cortical functioning and the developmental course of cognitive functions.


Assuntos
Cocaína/efeitos adversos , Potenciais Evocados/efeitos dos fármacos , Efeitos Tardios da Exposição Pré-Natal/psicologia , Criança , Feminino , Humanos , Masculino , Testes Neuropsicológicos , Gravidez
20.
Dev Neuropsychol ; 40(1): 1-6, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25649772

RESUMO

Although research into concussion has greatly expanded over the past decade, progress in identifying the mechanisms and consequences of head injury and recovery are largely absent. Instead, data are accumulated without the guidance of a systematic theory to direct research questions or generate testable hypotheses. As part of this special issue on sports concussion, I advance a theory that emphasizes changes in spatial and temporal distributions of the brain's neural networks during normal learning and the disruptions of these networks following injury. Specific predictions are made regarding both the development of the network as well as its breakdown following injury.


Assuntos
Concussão Encefálica , Lesões Encefálicas , Rede Nervosa , Traumatismos em Atletas , Humanos , Pesquisa , Medicina Esportiva/métodos
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