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2.
Brain Sci ; 13(5)2023 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-37239225

RESUMO

BACKGROUND: Preterm birth is one of the world's critical health problems, with an incidence of 5% to 18% of living newborns according to various countries. White matter injuries due to preoligodendrocytes deficits cause hypomyelination in children born preterm. Preterm infants also have multiple neurodevelopmental sequelae due to prenatal and perinatal risk factors for brain damage. The purpose of this work was to explore the effects of the brain risk factors and MRI volumes and abnormalities on the posterior motor and cognitive development at 3 years of age. METHODS: A total of 166 preterm infants were examined before 4 months and clinical and MRI evaluations were performed. MRI showed abnormal findings in 89% of the infants. Parents of all infants were invited to receive the Katona neurohabilitation treatment. The parents of 128 infants accepted and received Katona's neurohabilitation treatment. The remaining 38 infants did not receive treatment for a variety of reasons. At the three-year follow-up, Bayley's II Mental Developmental Index (MDI) and the Psychomotor Developmental Index (PDI) were compared between treated and untreated subjects. RESULTS: The treated children had higher values of both indices than the untreated. Linear regression showed that the antecedents of placenta disorders and sepsis as well as volumes of the corpus callosum and of the left lateral ventricle significantly predicted both MDI and PDI, while Apgar < 7 and volume of the right lateral ventricle predicted the PDI. CONCLUSIONS: (1) The results indicate that preterm infants who received Katona's neurohabilitation procedure exhibited significantly better outcomes at 3 years of age compared to those who did not receive the treatment. (2) The presence of sepsis and the volumes of the corpus callosum and lateral ventricles at 3-4 months were significant predictors of the outcome at 3 years of age.

4.
Neuroimage ; 252: 119035, 2022 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-35218932

RESUMO

INTRODUCTION: The maturation of electroencephalogram (EEG) effective connectivity in healthy infants during the first year of life is described. METHODS: Participants: A cross-sectional sample of 125 healthy at-term infants, from 0 to 12 months of age, underwent EEG in a state of quiet sleep. PROCEDURES: The EEG primary currents at the source were described with the sLoreta method. An unmixing algorithm was applied to reduce the leakage, and the isolated effective coherence, a direct and directed measurement of information flow, was calculated. RESULTS AND DISCUSSION: Initially, the highest indices of connectivity are at the subcortical nuclei, continuing to the parietal lobe, predominantly the right hemisphere, then expanding to temporal, occipital, and finally the frontal areas, which is consistent with the myelination process. Age-related connectivity changes were mostly long-range and bilateral. Connections increased with age, mainly in the right hemisphere, while they mainly decreased in the left hemisphere. Increased connectivity from 20 to 30 Hz, mostly at the right hemisphere. These findings were consistent with right hemisphere predominance during the first three years of life. Theta and alpha connections showed the greatest changes with age. Strong connectivity was found between the parietal, temporal, and occipital regions to the frontal lobes, responsible for executive functions and consistent with behavioral development during the first year. The thalamus exchanges information bidirectionally with all cortical regions and frequency bands. CONCLUSIONS: The maturation of EEG connectivity during the first year in healthy infants is very consistent with synaptogenesis, reductions in synaptogenesis, myelination, and functional and behavioral development.


Assuntos
Encéfalo , Eletroencefalografia , Mapeamento Encefálico/métodos , Estudos Transversais , Eletroencefalografia/métodos , Lobo Frontal , Humanos , Lactente
5.
Int J Psychophysiol ; 172: 17-23, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34921894

RESUMO

Cognitive deficits in infants born preterm and infants at term with risk factors for brain damage are a common outcome. Attention deficits in preterm infants are related to the development of attention-deficit/hyperactivity disorder (ADHD), and therefore, there is a need for earlier evaluations and treatment procedures that are implemented before the presence of signs of ADHD. METHODS: We studied preterm (74%) and term infants with the Infant Scale of Selective Attention (ISSA, Escala de Evaluación de la Atención Selectiva (EEAS), in Spanish). This scale evaluates both visual- and auditory-orienting attention. Two groups participated, one with attention deficits (n = 26) and another with regular performance (n = 36). An early attention-stimulation program (EASP) was implemented in the infant group with attention deficits from three to eight months of age. All infants underwent magnetic resonance imaging (MRI), and visual and auditory evoked responses were assessed. RESULTS: All infants had prenatal and perinatal risk factors for brain damage and abnormal MRI findings, and the majority had abnormalities compatible with white matter injury. However, there were four infants with porencephalic cysts; 3 of them were in the treated group. At the beginning of the treatment, ISSA values showed differences between groups. These differences persisted for five months in the visual test and up to the sixth month in the auditory evaluation. Afterward, there were no significant differences, indicating that infants with attention deficits had satisfactorily responded to the treatment. CONCLUSIONS: The ISSA is helpful for the early evaluation of visual and auditory attention. Infants with attention deficits react well enough after six months of EASP.


Assuntos
Transtorno do Deficit de Atenção com Hiperatividade , Lesões Encefálicas , Transtorno do Deficit de Atenção com Hiperatividade/diagnóstico , Transtorno do Deficit de Atenção com Hiperatividade/patologia , Transtorno do Deficit de Atenção com Hiperatividade/terapia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Lesões Encefálicas/patologia , Humanos , Lactente , Recém-Nascido , Recém-Nascido Prematuro/fisiologia , Imageamento por Ressonância Magnética/métodos , Fatores de Risco
6.
Neuroimage ; 235: 117984, 2021 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-33775809

RESUMO

Prenatal and perinatal risk factors for perinatal brain damage frequently produce brain injuries in preterm and term infants. The early diagnosis and treatment of these infants, in the period of higher brain plasticity, may prevent the neurological and cognitive sequels that accompany these lesions. The Neurodevelopmental Research Unit at the Institute of Neurobiology of the National Autonomous University of Mexico has taken this endeavor. A multidisciplinary approach is followed. Pediatric, neurologic and rehabilitation clinical studies, MRI, EEG, visual and auditory evoked responses, and Bayley II evaluations are carried out initially. Infants are followed up to 8 years, with periodic appointments for evaluation and treatment. Katona's neurohabilitation method is used for initial diagnosis and treatment. Selective visual and auditory attention are explored from 3 months of age. This method was created in the Unit and, if deficiencies are observed, the method also describes the treatment to avoid subsequent alterations of these processes. Deficiencies in the acquisition of language are evaluated from 4 months of age, implementing treatment through instructions to parents on how they should teach their children to speak. This method has also been developed in the Unit and is in its validation process. In the MRI, we pay special attention to subtle and diffuse patterns, due to the high frequency with which they appear in contemporary cohorts at a national and international level. More than 80% of these infants showed abnormal MRI findings that should be taken into consideration. The outcome of children at 8 years old showed that 78%, 76% and 78% of extremely preterm, very preterm and late preterm, respectively, had a normal neurodevelopment. In term infants, only 69% had a normal neurodevelopment; in this group, the majority of infants had very severe brain lesions. Conclusions: It is necessary to evaluate, at an early age, all newborns with prenatal and perinatal risk factors for brain damage. Special attention should be payed to all premature newborns and those newborns who have been discharged from the intensive care unit.


Assuntos
Lesões Encefálicas/diagnóstico , Lesões Encefálicas/reabilitação , Desenvolvimento Infantil/fisiologia , Diagnóstico Precoce , Intervenção Médica Precoce , Reabilitação Neurológica , Avaliação de Processos e Resultados em Cuidados de Saúde , Criança , Pré-Escolar , Feminino , Seguimentos , Humanos , Lactente , Recém-Nascido , Doenças do Recém-Nascido , Recém-Nascido Prematuro , Doenças do Prematuro , Unidades de Terapia Intensiva Neonatal , Imageamento por Ressonância Magnética , Masculino , México , Fatores de Risco
7.
Brain Sci ; 10(11)2020 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-33158135

RESUMO

Learning disorders (LDs) are diagnosed in children whose academic skills of reading, writing or mathematics are impaired and lagging according to their age, schooling and intelligence. Children with LDs experience substantial working memory (WM) deficits, even more pronounced if more than one of the academic skills is affected. We compared the task-related electroencephalogram (EEG) power spectral density of children with LDs (n = 23) with a control group of children with good academic achievement (n = 22), during the performance of a WM task. sLoreta was used to estimate the current distribution at the sources, and 18 brain regions of interest (ROIs) were chosen with an extended version of the eigenvector centrality mapping technique. In this way, we lessened some drawbacks of the traditional EEG at the sensor space by an analysis at the brain-sources level over data-driven selected ROIs. Results: The LD group showed fewer correct responses in the WM task, an overall slower EEG with more delta and theta activity, and less high-frequency gamma activity in posterior areas. We explain these EEG patterns in LD children as indices of an inefficient neural resource management related with a delay in neural maturation.

8.
Neurosci Lett ; 738: 135345, 2020 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-32882316

RESUMO

AIM: To determine the long-term efficacy of Katona therapy and early rehabilitation of infants with moderate-to-severe perinatal brain damage (PBD). METHODS: Thirty-two participants were recruited (7-16 years) and divided into 3 groups: one Healthy group (n = 11), one group with PBD treated with Katona methodology from 2 months of corrected age, and with long-term follow-up (n = 12), and one group with PBD but without treatment in the first year of life due to late diagnosis of PBD (n = 9). Neuropediatric evaluations, motor evoked potentials (MEPs) and magnetic resonance images (MRI) were made. The PBD groups were matched by severity and topography of lesion. RESULTS: The patients treated with Katona had better motor performance when compared to patients without early treatment (Gross Motor Function Classification System levels; 75% of Katona group were classified in levels I and II and 78% of patients without early treatment were classified in levels III and IV). Furthermore, independent k-means cluster analyses of MRI, MEPs, and neuropediatric evaluations data were performed. Katona and non-treated early groups were classified in the same MRI cluster which is the expected for PBD population patients. However, in MEPs and neuropediatric evaluations clustering, the 67% of Katona group were assigned into Healthy group showing the impact of Katona therapy over the patients treated with it. These results highlight the Katona therapy benefits in early rehabilitation of infants with moderate-to-severe PBD. CONCLUSIONS: Katona therapy and early rehabilitation have an important therapeutic effect in infants with moderate-to-severe PBD by decreasing the severity of motor disability in later stages of life.


Assuntos
Lesões Encefálicas/reabilitação , Encéfalo/fisiopatologia , Paralisia Cerebral/reabilitação , Reabilitação Neurológica/métodos , Adolescente , Encéfalo/diagnóstico por imagem , Lesões Encefálicas/diagnóstico por imagem , Lesões Encefálicas/fisiopatologia , Paralisia Cerebral/diagnóstico por imagem , Paralisia Cerebral/fisiopatologia , Criança , Avaliação da Deficiência , Potencial Evocado Motor/fisiologia , Feminino , Humanos , Recém-Nascido , Cooperação Internacional , Imageamento por Ressonância Magnética , Masculino , Gravidez
10.
Sleep ; 43(4)2020 04 15.
Artigo em Inglês | MEDLINE | ID: mdl-31650177

RESUMO

Spectral analysis of neonatal sleep is useful for studying brain maturation; however, most studies have analyzed conventional broad bands described for awake adults, so a distinct approach for EEG analysis may disclose new findings. STUDY OBJECTIVES: To extract independent EEG broad bands using principal component analysis (PCA) and describe week-by-week EEG changes in quiet sleep (QS) and active sleep (AS) during the first 5 weeks of postnatal life in healthy, full-term newborns. METHODS: Polysomnography of spontaneous sleep was recorded in 60 newborns in 5 groups at 41, 42, 43, 44, and 45 weeks (n = 12 each) postconceptional age (POST-C). QS and AS stages were identified. Absolute power (AP) for 1 Hz bins between 1 and 30 Hz was subjected to PCA to extract independent broad bands. RESULTS: PCA rendered three independent broad bands distinct from conventional bands. They explained 82.8% of variance: 2-10 Hz, 10-16 Hz, and 17-30 Hz. ANOVAs (group × age × derivations) showed significant higher power at 2-10 Hz with greater age, higher power in QS than AS in all three bands, and significantly higher AP in the left central region, and in the right occipital and temporal areas, in both sleep stages. CONCLUSION: A different method of analyzing sleep EEG generated new information on brain maturation. The Sigma frequencies identified suggest that sleep spindle maturation begins by at least 41 weeks of POST-C age. Interhemispheric asymmetries during sleep suggest earlier development of the central left region and the right occipital and temporal areas.


Assuntos
Eletroencefalografia , Fases do Sono , Adulto , Humanos , Recém-Nascido , Polissonografia , Sono , Sono REM
11.
J Vis Exp ; (152)2019 10 24.
Artigo em Inglês | MEDLINE | ID: mdl-31710028

RESUMO

The present study discusses the characteristics of visual event-related potentials (VEPs) and outlines methodological steps for obtaining reliable measurements in newborns. Obtaining high-quality, reliable VEPs is crucial for the early detection of abnormal development of the central nervous system in at-risk newborns, and for implementing successful early interventions. Recommendations are based on a previous study which showed that when post-conceptional age, polysomnography-identified sleep stages, and light-emitting diodes (LEDs) googles as the luminous source are controlled, no more than 4 repetitions of VEP averages are required to obtain replicable recordings, variability decreases, and reliable VEPs can be obtained. By controlling for these sources of variability and using statistical analyses, we were able to clearly and reliably identify the amplitude and latency of three main components (NII, PII and NIII) present in 100% of newborns (n = 20) during active sleep. Recording VEPs during awake states, quiet sleep and transitional sleep is not recommended because VEP morphology may differ significantly from one average to the next, leading to the risk of misleading clinical prognoses. Moreover, it is easier to obtain VEPs during active sleep because this state can be clearly and reliably identified at this stage of development, sleep cycles are short enough to allow measurements to be taken in a reasonable time, and the method does not require new o expensive equipment.


Assuntos
Potenciais Evocados Visuais/fisiologia , Feminino , Humanos , Recém-Nascido , Masculino
12.
Actual. psicol. (Impr.) ; 32(124): 52-64, ene.-jun. 2018. tab, graf
Artigo em Espanhol | LILACS, Index Psicologia - Periódicos, SaludCR | ID: biblio-1088555

RESUMO

Resumen Objetivo: Comparar dos sistemas de puntuación para un test de fluidez verbal con el Modelo de Escalas de Calificación. Método: Se analizaron datos de 289 participantes, de los cuales 92 habían sido diagnosticados con Parkinson. Las puntuaciones se calcularon con dos sistemas de categorización: un procedimiento convencional y otro basado en percentiles. Resultados: Las puntuaciones Rasch procedentes de percentiles dan lugar a categorías adecuadas y medidas fiables; la correlación con las puntuaciones del test Minimental es evidencia de validez concurrente. Tras controlar estadísticamente el efecto de la edad, las medidas Rasch procedentes de percentiles discriminan entre ambos grupos, lo que evidencia validez predictiva. Conclusiones: El análisis de los dos procedimientos permite recomendar el uso de las categorías basadas en percentiles.


Abstract Objective: Two scoring systems for a verbal fluency test were compared using the Rasch Rating Scale Model. Method: The analysis was carried out on 289 participants, 92 of whom had had a Parkinson's disease diagnosis. Scores were calculated with two different category systems: a conventional procedure and a percentile-based one. Results: The percentile-based Rasch scores produce adequate categories and reliable measures, while the correlation with the Mini Mental State Examination evinces concurrent validity. After statistically controlling for age, percentile-based Rasch measures discriminated between both groups, demonstrating predictive validity. Conclusions: The analysis of the two procedures allows for the recommendation of the use of percentile-based categories.


Assuntos
Humanos , Masculino , Feminino , Recém-Nascido , Lactente , Pais/psicologia , Estimulação Acústica/psicologia , Recém-Nascido Prematuro/crescimento & desenvolvimento , Linguagem Infantil , Intervenção Educacional Precoce/tendências , Desenvolvimento da Linguagem , Estimulação Física , México
13.
Int J Dev Neurosci ; 68: 26-34, 2018 08.
Artigo em Inglês | MEDLINE | ID: mdl-29698661

RESUMO

Morphology and late components of evoked potentials change depending on wake-sleep stages in adults. Visual Evoked potentials (VEPs) have been frequently studied in newborns to identify abnormal development of visual pathways; however, large variability has been reported and there is uncertainty as to the effect of sleep stages on VEPs in neonates. OBJECTIVE: To describe the characteristics of VEPs in one month old, healthy full-term newborns during active sleep (AS) and quiet sleep (QS), defined by simultaneous polysomnography (PSG). METHODS: VEPs were obtained by monocular LEDs stimulation of each eye during AS and QS, in 20 healthy full-term newborns (gestational age 37-40 weeks) with normal birth weights and normal prenatal Doppler ultrasound indices. Latencies and amplitudes of N2, P2 and N3 components in AS and QS were compared, and their association with absolute power of EEG frequency bands, assessed. RESULTS: There were no significant differences in VEP morphology, latencies and amplitudes between sleep states. Typical wave forms were obtained in all newborns in AS; however, no VEPs could be identified clearly in 3 newborns in QS; QS VEPs were less reliable than in AS: more averaging was required; correlation was significantly lower between the VEP averages; and a larger number of babies needed more than two averages to obtain replicable responses needed for clinical purposes. CONCLUSIONS: These results indicate that changes in amplitude and latency of some VEP components observed in NREM and REM sleep in adults are not yet present in one month old newborns probably due to immaturity of cortical and sleep mechanisms. VEPs are more reliable during AS than QS in newborns. Systematic VEP recording during AS, and polysomnographic control to identify this stage, are highly recommended as methods that can increase there liability of neonatal VEPs.


Assuntos
Potenciais Evocados Visuais/fisiologia , Recém-Nascido/fisiologia , Sono/fisiologia , Correlação de Dados , Eletroencefalografia , Feminino , Idade Gestacional , Humanos , Masculino , Estimulação Luminosa , Polissonografia , Tempo de Reação/fisiologia , Vigília/fisiologia
14.
J Clin Neurosci ; 45: 299-304, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28890038

RESUMO

Recent evidence suggests that Auditory Brainstem Responses (ABR), in neonates with risk factors for neurological damage, may show auditory brainstem abnormalities, even in patients with normal hearing. To compare the recording and diagnostic accuracy of neonatal Auditory Brainstem Responses (ABR), using 10 and 60clicks/s stimulation rates, two groups of neonates were prospectively studied: 30 healthy full-term neonates, with no peri- or postnatal complications; and 30 high-risk newborns with two or more of the following conditions: hyperbilirubinemia, use of ototoxic drugs, birth weight inferior to 1500g, perinatal sepsis, intraventricular hemorrhage, and/or mechanical ventilation. Correlation between ABR trials, recording duration, and the absolute and interpeak latencies of ABR waves I, III and V, were measured. ROC-curve analysis assessed the diagnostic accuracy of both stimulation rates. The correlations between ABRs trials were significantly higher at 60clicks/s than at 10clicks/s (F(1,116)=14.5, p<0.0002). Recording duration at 60clicks/s was significantly lower (t=20.9, p<0.0001). ROC-curve comparisons showed increased diagnostic accuracy at the stimulation rate of 60clicks/s, for waves I (D=2.04, p=0.04), V (D=2.02, p=0.04), interpeak latencies III-V (D=2.2, p=0.02), and I-V (D=2.86, p=0.004). In neonates, the use of 60clicks/s stimulation rate permits a substantial shortening of the ABR recording, with greater diagnostic accuracy and replicability.


Assuntos
Estimulação Acústica/métodos , Potenciais Evocados Auditivos do Tronco Encefálico/fisiologia , Valor Preditivo dos Testes , Complicações na Gravidez/diagnóstico , Complicações na Gravidez/fisiopatologia , Técnicas de Diagnóstico Neurológico , Feminino , Humanos , Recém-Nascido , Masculino , Gravidez , Estudos Prospectivos , Fatores de Risco , Fatores de Tempo
15.
Neuroimage Clin ; 16: 355-368, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28861337

RESUMO

Perinatal care advances emerging over the past twenty years have helped to diminish the mortality and severe neurological morbidity of extremely and very preterm neonates (e.g., cystic Periventricular Leukomalacia [c-PVL] and Germinal Matrix Hemorrhage - Intraventricular Hemorrhage [GMH-IVH grade 3-4/4]; 22 to < 32 weeks of gestational age, GA). However, motor and/or cognitive disabilities associated with mild-to-moderate white and gray matter injury are frequently present in this population (e.g., non-cystic Periventricular Leukomalacia [non-cystic PVL], neuronal-axonal injury and GMH-IVH grade 1-2/4). Brain research studies using magnetic resonance imaging (MRI) report that 50% to 80% of extremely and very preterm neonates have diffuse white matter abnormalities (WMA) which correspond to only the minimum grade of severity. Nevertheless, mild-to-moderate diffuse WMA has also been associated with significant affectations of motor and cognitive activities. Due to increased neonatal survival and the intrinsic characteristics of diffuse WMA, there is a growing need to study the brain of the premature infant using non-invasive neuroimaging techniques sensitive to microscopic and/or diffuse lesions. This emerging need has led the scientific community to try to bridge the gap between concepts or ideas from different methodologies and approaches; for instance, neuropathology, neuroimaging and clinical findings. This is evident from the combination of intense pre-clinical and clinicopathologic research along with neonatal neurology and quantitative neuroimaging research. In the following review, we explore literature relating the most frequently observed neuropathological patterns with the recent neuroimaging findings in preterm newborns and infants with perinatal brain injury. Specifically, we focus our discussions on the use of neuroimaging to aid diagnosis, measure morphometric brain damage, and track long-term neurodevelopmental outcomes.


Assuntos
Doenças do Prematuro/diagnóstico por imagem , Imageamento por Ressonância Magnética/métodos , Substância Branca/diagnóstico por imagem , Humanos , Recém-Nascido , Recém-Nascido Prematuro
16.
PLoS One ; 12(7): e0179556, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28708890

RESUMO

Electroencephalographic alterations have been reported in subjects with learning disorders, but there is no consensus on what characterizes their electroencephalogram findings. Our objective was to determine if there were subgroups within a group of scholars with not otherwise specified learning disorders and if they had specific electroencephalographic patterns. Eighty-five subjects (31 female, 8-11 years) who scored low in at least two subscales -reading, writing and arithmetic- of the Infant Neuropsychological Evaluation were included. Electroencephalograms were recorded in 19 leads during rest with eyes closed; absolute power was obtained every 0.39 Hz. Three subgroups were formed according to children's performance: Group 1 (G1, higher scores than Group 2 in reading speed and reading and writing accuracy), Group 2 (G2, better performance than G1 in composition) and Group 3 (G3, lower scores than Groups 1 and 2 in the three subscales). G3 had higher absolute power in frequencies in the delta and theta range at left frontotemporal sites than G1 and G2. G2 had higher absolute power within alpha frequencies than G3 and G1 at the left occipital site. G3 had higher absolute power in frequencies in the beta range than G1 in parietotemporal areas and than G2 in left frontopolar and temporal sites. G1 had higher absolute power within beta frequencies than G2 in the left frontopolar site. G3 had lower gamma absolute power values than the other groups in the left hemisphere, and gamma activity was higher in G1 than in G2 in frontopolar and temporal areas. This group of children with learning disorders is very heterogeneous. Three subgroups were found with different cognitive profiles, as well as a different electroencephalographic pattern. It is important to consider these differences when planning interventions for children with learning disorders.


Assuntos
Encéfalo/diagnóstico por imagem , Eletroencefalografia , Deficiências da Aprendizagem/diagnóstico , Criança , Análise por Conglomerados , Feminino , Humanos , Deficiências da Aprendizagem/diagnóstico por imagem , Masculino , Matemática , Leitura , Redação
17.
Appl Psychophysiol Biofeedback ; 42(4): 257-267, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28735381

RESUMO

The sensorimotor rhythm (SMR) is an electroencephalographic rhythm associated with motor and cognitive development observed in the central brain regions during wakefulness in the absence of movement, and it reacts contralaterally to generalized and hemibody movements. The purpose of this work was to characterize the SMR of 4-month-old infants, born either healthy at term or prematurely with periventricular leukomalacia (PVL). Two groups of infants were formed: healthy and premature with PVL. Their electroencephalograms (EEGs) were recorded in four conditions: rest, free movement, right-hand grasping and left-hand grasping, in order to explore general reactivity to free movement and contralateral reactivity in hand-grasping conditions. Associations between SMR, and cognitive and motor performance were analyzed. The healthy infants showed a SMR between 5.47 and 7.03 Hz, with clear contralateral reactivity to free movement and right-hand grasping. However, the premature infants with PVL did not show enough electroencephalographic characteristics to evidence the presence of SMR. Poor performance, characteristic of children with PVL, was related to low-frequency SMR, while good performance was associated with a higher frequency rhythm in the left hemisphere. The presence of SMR in the group of healthy infants could be considered a sign of health at this age. Thus, poor SMR evidence in the EEG of infants with PVL is probably a sign of brain immaturity or brain dysfunction. Our results provide data on infant SMR development that is needed to design neurofeedback protocols for infants with PVL.


Assuntos
Ondas Encefálicas/fisiologia , Encéfalo/fisiologia , Desenvolvimento Infantil/fisiologia , Recém-Nascido Prematuro/fisiologia , Leucomalácia Periventricular/fisiopatologia , Encéfalo/crescimento & desenvolvimento , Encéfalo/fisiopatologia , Feminino , Humanos , Lactente , Masculino
18.
Clin EEG Neurosci ; 48(2): 88-95, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27170673

RESUMO

The rate of premature births has increased in the past 2 decades. Ten percent of premature birth survivors develop motor impairment, but almost half exhibit later sensorial, cognitive, and emotional disabilities attributed to white matter injury and decreased volume of neuronal structures. The aim of this study was to test the hypothesis that premature and full-term infants differ in their development of emotional face processing. A comparative longitudinal study was conducted in premature and full-term infants at 4 and 8 months of age. The absolute power of the electroencephalogram was analyzed in both groups during 5 conditions of an emotional face processing task: positive, negative, neutral faces, non-face, and rest. Differences between the conditions of the task at 4 months were limited to rest versus non-rest comparisons in both groups. Eight-month-old term infants had increases ( P ≤ .05) in absolute power in the left occipital region at the frequency of 10.1 Hz and in the right occipital region at 3.5, 12.8, and 16.0 Hz when shown a positive face in comparison with a neutral face. They also showed increases in absolute power in the left occipital region at 1.9 Hz and in the right occipital region at 2.3 and 3.5 Hz with positive compared to non-face stimuli. In contrast, positive, negative, and neutral faces elicited the same responses in premature infants. In conclusion, our study provides electrophysiological evidence that emotional face processing develops differently in premature than in full-term infants, suggesting that premature birth alters mechanisms of brain development, such as the myelination process, and consequently affects complex cognitive functions.


Assuntos
Envelhecimento/fisiologia , Eletroencefalografia/métodos , Emoções/fisiologia , Expressão Facial , Recém-Nascido Prematuro/crescimento & desenvolvimento , Lobo Occipital/fisiologia , Discriminação Psicológica/fisiologia , Feminino , Humanos , Lactente , Masculino , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Percepção Visual/fisiologia
19.
Front Neurosci ; 11: 749, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-29379411

RESUMO

In this paper, we present a novel methodology to solve the classification problem, based on sparse (data-driven) regressions, combined with techniques for ensuring stability, especially useful for high-dimensional datasets and small samples number. The sensitivity and specificity of the classifiers are assessed by a stable ROC procedure, which uses a non-parametric algorithm for estimating the area under the ROC curve. This method allows assessing the performance of the classification by the ROC technique, when more than two groups are involved in the classification problem, i.e., when the gold standard is not binary. We apply this methodology to the EEG spectral signatures to find biomarkers that allow discriminating between (and predicting pertinence to) different subgroups of children diagnosed as Not Otherwise Specified Learning Disabilities (LD-NOS) disorder. Children with LD-NOS have notable learning difficulties, which affect education but are not able to be put into some specific category as reading (Dyslexia), Mathematics (Dyscalculia), or Writing (Dysgraphia). By using the EEG spectra, we aim to identify EEG patterns that may be related to specific learning disabilities in an individual case. This could be useful to develop subject-based methods of therapy, based on information provided by the EEG. Here we study 85 LD-NOS children, divided in three subgroups previously selected by a clustering technique over the scores of cognitive tests. The classification equation produced stable marginal areas under the ROC of 0.71 for discrimination between Group 1 vs. Group 2; 0.91 for Group 1 vs. Group 3; and 0.75 for Group 2 vs. Group1. A discussion of the EEG characteristics of each group related to the cognitive scores is also presented.

20.
Rev. chil. neuropsicol. (En línea) ; 11(2): 13-21, dic. 2016. ilus, tab
Artigo em Espanhol | LILACS | ID: biblio-869796

RESUMO

En el presente trabajo se compararon dos grupos de niños mexicanos en edades comprendidas entre los 8 a 10 años, el primer grupo con trastorno específico en el aprendizaje (TEA), tanto en la precisión de la lectura como en el cálculo, y el otro con buen desempeño académico (BDA), por medio de Escala Wechsler de Inteligencia para Niños, en su cuarta versión (WISC-IV) y la batería de Evaluación Neuropsicológica Infantil (ENI), (subpruebas de Habilidades Académicas, Memoria, Atención y Habilidades Metalingüísticas), ambos instrumentos normados en población mexicana. Se encontraron diferencias significativas (p≤ 0.05) entre los niños BDA y TEA, mediante la U de Mann Whitney, en todas las subpruebas evaluadas a excepción del Índice Velocidad de Procesamiento (WISC), Conteo, Codificación/Evocación y Atención Auditiva, además de Atención visual (ENI). Mediante el Análisis de Componentes Principales se identificaron 5 subgrupos: 2 en los niños con BDA y 3 en los TEA. Las diferencias significativas (p≤ 0.05)entre las variables cognitivas y académicas fueron determinadas mediante la prueba de Kruskal-Wallis. Fue posible observar que los subgrupos TEA obtuvieron puntajes más bajos que los subgrupos BDA tanto en habilidades académicas como en otras variables cognitivas,siendo el Índice de Memoria de Trabajo en la escala Wechsler y las Habilidades Metalingüísticas de la ENI las que mejor diferenciaron a los subgrupos TEA de los BDA.Conclusión: La aplicación de instrumentos normados en la población bajo estudio resulta de gran utilidad para identificar subtipos neuropsicológicos tantoen niños con BDA como con TEA.


In this work two groups of Mexican children aged between 8 to 10 years old were compared, the first group with specific learningdisorder (SLD),in both reading accuracy as in the calculation, and the other compared to good performance academic (GPA) by Wechsler Intelligence Scale for Children, in its fourth version (WISC-IV) and battery Child Neuropsychological Assessment (ENI), (subtests Academic Skills, Memory, Attention and Metalinguistic Skills), both instruments normed in Mexican population. Significant differences (p ≤ 0.05) were found among SLD and GPA children, by Mann Whitney U Test, they were found in all subtests evaluated except Processing Speed Rate (WISC), Counting, Coding / Evocation and Auditory Attention, also Visual Attention (ENI). By the Principal Component Analysis were identified five subgroups: 2 children with GPA and 3 in the SLD. Significant differences (p ≤ 0.05) between cognitive and academic variables were determined by the Kruskal-Wallis Test. It was possible to observe that the TEA subgroups scored lower than the BDA subgroups in academic abilities as well as in other cognitive variables, with the Working Memory Index on the Wechsler scale as the subtests that evaluate the ENI Metalinguistic Skills the variables that give the best discrimination between the TEA and the BDA subgroups.Conclusion: The application of normed instruments in the population under study is useful to identify neuropsychological subtypes in children with GPA as SLD.


Assuntos
Humanos , Masculino , Feminino , Criança , Linguística , Memória de Curto Prazo , Transtorno de Aprendizagem Específico/diagnóstico , Testes de Inteligência , México , Testes Neuropsicológicos , Análise de Componente Principal
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