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Development of the cerebral cortex may be affected by aberrant white matter development. Preterm birth with very low birth weight (VLBW) has been associated with reduced fractional anisotropy of white matter and changes in cortical thickness and surface area. We use a new methodological approach to combine white and gray matter data and test the hypothesis that white matter injury is primary, and acts as a mediating factor for concomitant gray matter aberrations, in the developing VLBW brain. T1 and dMRI data were obtained from 47 young adults born preterm with VLBW and 73 term-born peers (mean ageâ¯=â¯26). Cortical thickness was measured across the cortical mantle and compared between the groups, using the FreeSurfer software suite. White matter pathways were reconstructed with the TRACULA software and projected to their cortical end regions, where cortical thickness was averaged. In the VLBW group, cortical thickness was increased in anteromedial frontal, orbitofrontal, and occipital regions, and fractional anisotropy (FA) was reduced in frontal lobe pathways, indicating compromised white matter integrity. Statistical mediation analyses demonstrated that increased cortical thickness in the frontal regions was mediated by reduced FA in the corpus callosum forceps minor, consistent with the notion that white matter injury can disrupt frontal lobe cortical development. Combining statistical mediation analysis with pathway projection onto the cortical surface offers a powerful novel tool to investigate how cortical regions are differentially affected by white matter injury.
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Córtex Cerebral/patologia , Recém-Nascido de muito Baixo Peso , Nascimento Prematuro/patologia , Substância Branca/patologia , Adulto , Anisotropia , Córtex Cerebral/crescimento & desenvolvimento , Feminino , Substância Cinzenta/crescimento & desenvolvimento , Substância Cinzenta/patologia , Humanos , Masculino , Substância Branca/crescimento & desenvolvimento , Substância Branca/lesõesRESUMO
Individuals born preterm with very low birth weight (VLBW; birth weight ≤ 1500 g) are at high risk for perinatal brain injuries and deviant brain development, leading to increased chances of later cognitive, emotional, and behavioral problems. Here we investigated the neuronal underpinnings of both reactive and proactive cognitive control processes in adults with VLBW. We included 32 adults born preterm with VLBW (before 37th week of gestation) and 32 term-born controls (birth weight ≥10th percentile for gestational age) between 22 and 24 years of age that have been followed prospectively since birth. Participants performed a well-validated Not-X continuous performance test (CPT) adapted for use in a mixed block- and event-related fMRI protocol. BOLD fMRI and DTI data was acquired on a 3T scanner. Performance on the Not-X CPT was highly similar between groups. However, the VLBW group demonstrated hyper-reactive cognitive control processing and disrupted white matter organization. The hyper-reactive brain activation signature in VLBW adults was associated with lower gestational age, lower fluid intelligence score, and anxiety problems. Automated Multi-Atlas Tract Extraction (AutoMATE) analyses revealed that this disruption of normal brain function was accompanied by poorer white matter organization in the anterior thalamic radiation and the cingulum, as reflected in both reduced fractional anisotropy and increased mean diffusivity. These findings show that the preterm behavioral phenotype is associated with predominantly reactive-, rather than proactive cognitive control processing, as well as white matter abnormalities, that may underlie common difficulties that many preterm born individuals experience in everyday life.
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Função Executiva/fisiologia , Desenvolvimento Humano/fisiologia , Recém-Nascido Prematuro/fisiologia , Recém-Nascido de muito Baixo Peso/fisiologia , Inteligência/fisiologia , Desempenho Psicomotor/fisiologia , Substância Branca/patologia , Adulto , Imagem de Tensor de Difusão , Feminino , Seguimentos , Humanos , Imageamento por Ressonância Magnética , Masculino , Substância Branca/diagnóstico por imagem , Adulto JovemRESUMO
The hippocampi are regarded as core structures for learning and memory functions, which is important for daily functioning and educational achievements. Previous studies have linked reduction in hippocampal volume to working memory problems in very low birth weight (VLBW; ≤ 1500 g) children and reduced general cognitive ability in VLBW adolescents. However, the relationship between memory function and hippocampal volume has not been described in VLBW subjects reaching adulthood. The aim of the study was to investigate memory function and hippocampal volume in VLBW young adults, both in relation to perinatal risk factors and compared to term born controls, and to look for structure-function relationships. Using Wechsler Memory Scale-III and MRI, we included 42 non-disabled VLBW and 61 control individuals at age 19-20 years, and related our findings to perinatal risk factors in the VLBW-group. The VLBW young adults achieved lower scores on several subtests of the Wechsler Memory Scale-III, resulting in lower results in the immediate memory indices (visual and auditory), the working memory index, and in the visual delayed and general memory delayed indices, but not in the auditory delayed and auditory recognition delayed indices. The VLBW group had smaller absolute and relative hippocampal volumes than the controls. In the VLBW group inferior memory function, especially for the working memory index, was related to smaller hippocampal volume, and both correlated with lower birth weight and more days in the neonatal intensive care unit (NICU). Our results may indicate a structural-functional relationship in the VLBW group due to aberrant hippocampal development and functioning after preterm birth.
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Hipocampo/crescimento & desenvolvimento , Recém-Nascido de muito Baixo Peso/psicologia , Memória/fisiologia , Nascimento Prematuro/psicologia , Feminino , Humanos , Interpretação de Imagem Assistida por Computador , Recém-Nascido , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Adulto JovemRESUMO
OBJECTIVES: To examine brain volumes and cortical surface area and thickness and to relate these brain measures to cognitive function in young adults born small for gestational age (SGA) at term compared with non-SGA control patients. STUDY DESIGN: This population-based follow-up study at age 20 years included 58 term-born SGA (birth weight <10th percentile, mean: 2915 g) and 81 non-SGA controls (birth weight ≥ 10th percentile, mean: 3707 g). Brain volumes and cortical surface area and thickness were investigated with magnetic resonance imaging, which was successfully obtained in 47 SGA patients and 61 control patients. Cognitive function was assessed using the Wechsler Adult Intelligence Scale, 3rd edition. A subgroup analysis was performed in the SGA group among subjects diagnosed with fetal growth restriction (FGR) based on repeated fetal ultrasound measurements. RESULTS: The SGA group showed regional reductions in cortical surface area, particularly in the frontal, parietal, and temporal lobes. Total brain volume, cortical gray matter, cerebral white matter, and putamen volumes were reduced in the SGA group compared with control patients, but there were no differences in specific subcortical brain structure volumes when correcting for intracranial volume. Reductions were most pronounced among SGA subjects with FGR. No associations were found between brain measures and IQ measures in either group. CONCLUSION: Young adults born SGA at term show a global reduction in brain volume as well as regional reductions in cortical surface area. We speculate whether these reductions may be confined to those exposed to FGR. None of the brain measures correlated with cognition.
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Encéfalo/patologia , Cognição/fisiologia , Retardo do Crescimento Fetal/patologia , Recém-Nascido Pequeno para a Idade Gestacional , Adulto , Feminino , Seguimentos , Idade Gestacional , Humanos , Testes de Inteligência , Imageamento por Ressonância Magnética , Masculino , Adulto JovemRESUMO
Executive functions are goal-directed control mechanisms that modulate the operation of other cognitive processes. Preterm born very-low-birth-weight (VLBW: birth weight<1500 grams) children have more problems with attention/executive function than their term born peers. The objective of this study is to examine if VLBW young adults had more self-reported attention/ executive problems and lower neuropsychological test results than controls. Furthermore, to investigate the relationship between self-reported attention/executive problems, general cognitive ability (IQ) and test results. Forty-two VLBW [mean birth weight 1237 (219) grams, and gestational age 29.3 (2.4) weeks] and 63 term born controls at age 19 years completed The BRIEF-A self-report of attention/executive functions in everyday life. The Wechsler Adult Intelligence Scale III was used to obtain IQ scores; subtests from Delis-Kaplan were used to assess attention/executive function. There were no differences between the VLBW young adults and controls on any of the BRIEF-A measures, but the VLBW subjects had lower scores on 8 of the 18 neuropsychological subtests (p<.01). Some correlations between BRIEF-A and the Stroop and TMT tests were found in the VLBW group. VLBW young adults do not report more problems regarding attention/executive function in daily life than controls despite lower results on several neuropsychological tests.
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Cognição/fisiologia , Recém-Nascido de muito Baixo Peso/fisiologia , Recém-Nascido de muito Baixo Peso/psicologia , Testes Neuropsicológicos , Autorrelato , Atenção , Função Executiva , Feminino , Idade Gestacional , Humanos , Estudos Longitudinais , Masculino , Noruega , Estatísticas não Paramétricas , Adulto JovemRESUMO
Reduced IQ, learning difficulties and poor school performance have been reported in small-for-gestational-age (SGA) subjects. However, few studies include a comprehensive neuropsychological assessment. Our aim was to study neuropsychological functioning in young adults born SGA at term. A comprehensive neuropsychological test battery was administered to 58 SGA subjects (birth weight <10th centile) born at term, and 81 term non-SGA controls (birth weight ≥10th centile). The SGA group obtained significantly (p < .01) lower scores on the attention, executive and memory domains compared to non-SGA controls and showed higher risk of obtaining scores below -1.5 SD on the memory domain (odds ratio = 13.3, 95% confidence interval: 1.57, 112.47). At a subtest level, the SGA group obtained lower scores on most neuropsychological tests, with significant differences on 6 of 46 measures: the Trail Making Test 3 (letter sequencing), the Wechsler Memory Scale mental control and the auditory immediate memory scale, the Design Fluency, the Stroop 3 (inhibition) and the Visual Motor Integration (VMI) motor coordination subtest. Young adults born SGA score more poorly on neuropsychological tests compared with non-SGA controls. Differences were modest, with more significant differences in the memory domain.
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Transtornos Cognitivos , Recém-Nascido Pequeno para a Idade Gestacional , Testes Neuropsicológicos , Adulto , Transtornos Cognitivos/diagnóstico , Transtornos Cognitivos/epidemiologia , Transtornos Cognitivos/etiologia , Feminino , Humanos , Masculino , Estatísticas não ParamétricasRESUMO
OBJECTIVE: To examine the effect on adult cognitive function of being born small for gestational age (SGA), and to evaluate whether cognitive function is related to intrauterine growth restriction (IUGR). STUDY DESIGN: Fifty-nine SGA subjects (birth weight <10th percentile) and 81 controls (birth weight ≥10th percentile) born at term underwent cognitive assessment with the Wechsler Adult Intelligence Scale-Third Edition at age 19-20 years. Repeated ultrasound measures of fetal growth were available for weeks 25, 33, and 37 in a subgroup of 29 SGA subjects and 75 control subjects, and these were data used to dichotomize the 29 SGA subjects into those with IUGR and those without IUGR. IUGR was defined as growth deviating more than -2 SD from the mean value of the control group. The effect of maternal smoking during pregnancy was considered as well. Group differences were analyzed using a general linear model, controlling for sex and socioeconomic status. RESULTS: The SGA group had lower full IQ scores than the control group (mean difference, -6.3; 95% CI, -2.8 to -9.7; P = .001), including lower scores on 6 of the Wechsler Adult Intelligence Scale-Third Edition subtests. In the SGA subgroup with repeated ultrasound measures, 6 of 29 subjects (21%) had IUGR, and these subjects also had a lower IQ compared with controls (mean difference, -14.0; 95% CI: -4.8 to -23.3; P = .003). Maternal smoking during pregnancy was related to lower IQ in the control group but not in the SGA group, independent of IUGR or non-IUGR status. CONCLUSION: IQ scores were lower in young adults born SGA compared with controls. Our analysis suggest that this outcome is related to IUGR.
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Cognição , Retardo do Crescimento Fetal , Recém-Nascido Pequeno para a Idade Gestacional , Transtornos Cognitivos/etiologia , Feminino , Humanos , Recém-Nascido , Testes de Inteligência , Masculino , Estudos Prospectivos , Adulto JovemRESUMO
BACKGROUND: Being born with low birth weight may have an impact on different aspects of mental health, psychosocial functioning and well-being; however results from studies in young adulthood have so far yielded mixed findings. The aim of this study was to assess the long-term impact in young adulthood on self-reported mental health, health-related quality of life, self-esteem and social relations by investigating differences between two low birth weight groups and a control group. METHODS: In a follow-up at 20 years of age, 43 preterm VLBW (birth weight ≤ 1500 g), 55 term SGA (birth weight < 10th percentile) and 74 control subjects completed the Adult Self-Report (ASR) of the Achenbach System of Empirically Based Assessment, the Adult Autism Spectrum Quotient (AQ), the Short Form 36 Health Survey, the Self-Perception Profile for Adolescents-Revised, and the Wechsler Adult Intelligent Scale III assessment. RESULTS: The VLBW and SGA groups reported significantly more mental health problems than controls. The VLBW group predominantly had internalizing problems, and the non-significant association with ASR Total score was reduced by the Intelligence Quotient (IQ). The SGA group had increased scores on both internalizing and externalizing problems, and the association with ASR Total score remained significant after adjusting for IQ in this group. Both low birth weight groups reported less interaction with friends and lower quality of life related to mental health domains than controls. Self-esteem scores were lower than in the control group for athletic competence (VLBW) and social acceptance (SGA). CONCLUSION: Our findings suggest that self-reported mental health and well-being in young adulthood may be adversely affected by low birth weight, irrespective of whether this is the result of premature birth or being born SGA at term.
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Nível de Saúde , Recém-Nascido de Baixo Peso/psicologia , Relações Interpessoais , Saúde Mental , Qualidade de Vida/psicologia , Feminino , Seguimentos , Humanos , Recém-Nascido , Recém-Nascido Pequeno para a Idade Gestacional/psicologia , Recém-Nascido de muito Baixo Peso/psicologia , Masculino , Transtornos Mentais/epidemiologia , Noruega/epidemiologia , Inquéritos e Questionários , Adulto JovemRESUMO
OBJECTIVE: To evaluate the effect of a computerized working memory training program on both trained and non-trained verbal aspects of working memory and executive and memory functions in extremely low birth weight (ELBW; <1000 g) infants. STUDY DESIGN: Sixteen ELBW infants and 19 term-born control subjects aged 14 to 15 years participated in the training program, and 11 adolescents were included as a non-intervention group. Extensive neuropsychological assessment was performed before and immediately after training and at a 6-month follow-up examination. Both training groups used the CogMed RM program at home 5 days a week for 5 weeks. RESULTS: Both groups improved significantly on trained and non-trained working memory tasks and on other memory tests indicating a generalizing effect. Working memory capacity was improved, and effects were maintained at the 6-month follow-up examination. There was no significant improvement in the non-intervention group at the 6-week follow-up examination. CONCLUSIONS: The computerized training program Cogmed RM was an effective intervention tool for improving memory and reducing core learning deficits in adolescents born at ELBW.
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Recém-Nascido de Peso Extremamente Baixo ao Nascer , Memória de Curto Prazo , Instruções Programadas como Assunto , Adolescente , Deficiências do Desenvolvimento , Seguimentos , Humanos , Recém-Nascido , Testes Neuropsicológicos , Classe Social , Aprendizagem VerbalRESUMO
Working memory training (WMT) effects may be modulated by mild cognitive impairment (MCI) subtypes, and variations in APOE-epsilon (APOE-ε) and LMX1A genotypes. Sixty-one individuals (41 men/20 women, mean age 66 years) diagnosed with MCI (31 amnestic/30 non-amnestic) and genotyped for APOE-ε and LMX1A completed 4 weeks/20-25 sessions of WMT. Cognitive functions were assessed before, 4 weeks and 16 weeks after WMT. Except for Processing Speed, the non-amnestic MCI group (naMCI) outperformed the amnestic MCI (aMCI) group in all cognitive domains across all time-points. At 4 weeks, working memory function improved in both groups (p < 0.0001), but at 16 weeks the effects only remained in the naMCI group. Better performance was found after training for the naMCI patients with LMX1A-AA genotype and for the APOE-ε4 carriers. Only the naMCI-APOE-ε4 group showed improved Executive Function at 16 weeks. WMT improved working memory and some non-trained cognitive functions in individuals with MCI. The naMCI group had greater training gain than aMCI group, especially in those with LMX1A-AA genotype and among APOE-ε4-carriers. Further research with larger sample sizes for the subgroups and longer follow-up evaluations is warranted.
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AIM: the aim of this study was to assess cognitive function at the age of 19 years in individuals of very low birthweight (VLBW; ≤ 1500g) and in term-born comparison individuals. METHOD: in this hospital-based follow-up study, 55 VLBW participants (30 males, 25 females; mean birthweight 1217g, SD 233g; mean gestational age 29.1wks, SD 2.5wks) and 81 comparison individuals (42 males, 39 females; mean birthweight 3707g, SD 433g; mean gestational age 39.7wks, SD 1.2wks) were examined with a standardized IQ test (Wechsler Adult Intelligence Scale III) to assess general cognitive ability. RESULTS: over half (53%) of the VLBW participants achieved a low IQ score (defined as >1SD below the mean in the comparison group; odds ratio 6.4 vs comparison individuals; 95% confidence interval 2.8-14.4; p<0.001). None of the VLBW group, compared with 22% of the comparison individuals, achieved a high IQ score (>1SD above the comparison mean). VLBW participants scored lower than comparison individuals on full, verbal, and performance IQ, as well as on all four indices (p ≤0.001). The subtest profile indicated problems on all subtests, but especially on those related to arithmetic and visual-perceptual tasks. INTERPRETATIONS: few studies have undertaken a comprehensive assessment of general cognitive outcome (IQ) among young adults of VLBW. Our results indicate that VLBW seems to have a global and lasting impact on cognitive ability. Full-scale IQ assessment may reveal important learning problems in young adults of VLBW, and should be performed to inform appropriate assistance to enhance academic achievement and the chances of permanent employment as adults.
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Desenvolvimento Infantil/fisiologia , Cognição/fisiologia , Recém-Nascido de muito Baixo Peso , Nascimento Prematuro/fisiopatologia , Logro , Feminino , Idade Gestacional , Humanos , Recém-Nascido , Inteligência , Estudos Longitudinais , Masculino , Testes Neuropsicológicos , Estigma Social , Estatística como Assunto , Estatísticas não Paramétricas , Adulto JovemRESUMO
[This corrects the article DOI: 10.3389/fnagi.2018.00384.].
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OBJECTIVE: We investigated if a 5-week computerized adaptive working memory training program (Cogmed®) of 20 to 25 sessions would be effective in improving the working memory capacity and other neuropsychological functions compared to a non-adaptive working memory training program (active-controlled) in adult patients with mild cognitive impairment (MCI). METHODS: This randomized double-blinded active control trial included 68 individuals aged 43 to 88 years, 45 men and 23 women, who were diagnosed with MCI at four Memory clinics. The study sample was randomized by block randomization to either adaptive or non-adaptive computerized working memory training. All participants completed the training, and were assessed with a comprehensive neuropsychological test battery before the intervention, and at 1 and 4 months after training. RESULTS: Compared to the non-adaptive training group, the adaptive training group did not show significantly greater improvement on the main outcome of working memory performance at 1 and 4 months after training. CONCLUSION: No difference were found between the two types of training on the primary outcome of working memory, or on secondary outcomes of cognitive function domains, in this sample of MCI patients. Hence, the hypothesis that the adaptive training program would lead to greater improvements compared to the non-adaptive training program was not supported. Within group analyses was not performed due to the stringent RCT design.
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In this cross-sectional study, we sought to describe cognitive and neuroimaging profiles of Memory clinic patients with Mild Cognitive Impairment (MCI). 51 MCI patients and 51 controls, matched on age, sex, and socio-economic status (SES), were assessed with an extensive neuropsychological test battery that included a measure of intelligence (General Ability Index, "GAI," from WAIS-IV), and structural magnetic resonance imaging (MRI). MCI subtypes were determined after inclusion, and z-scores normalized to our control group were generated for each cognitive domain in each MCI participant. MR-images were scored by visual rating scales. MCI patients performed significantly worse than controls on 23 of 31 cognitive measures (Bonferroni corrected p = 0.001), and on 8 of 31 measures after covarying for intelligence (GAI). Compared to nonamnestic MCI patients, amnestic MCI patients had lower test results in 13 of 31 measures, and 5 of 31 measures after co-varying for GAI. Compared to controls, the MCI patients had greater atrophy on Schelten's Medial temporal lobe atrophy score (MTA), especially in those with amnestic MCI. The only structure-function correlation that remained significant after correction for multiple comparisons was the MTA-long delay recall domain. Intelligence operationalized as GAI appears to be an important moderator of the neuropsychological outcomes. Atrophy of the medial temporal lobe, based on MTA scores, may be a sensitive biomarker for the functional episodic memory deficits associated with MCI.
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While cross-sectional neuroimaging studies on cortical development predict reductions in cortical volume (surface area and thickness) during adolescence, this is the first study to undertake a longitudinal assessment of cortical surface area changes across the continuous cortical surface during this period. We studied the developmental dynamics of cortical surface area and thickness in adolescents and young adults (aged 15-20) born with very low birth weight (VLBW; <1500 g) as well as in term-born controls. Previous studies have demonstrated brain structural abnormalities in cortical morphology, as well as long-term motor, cognitive and behavioral impairments, in adolescents and young adults with VLBW, but the developmental dynamics throughout adolescence have not been fully explored. T1-weighted MRI scans from 51 VLBW (27 scanned twice) and 79 term-born adolescents (37 scanned twice) were used to reconstruct the cortical surface and produce longitudinal estimates of cortical surface area and cortical thickness. Linear mixed model analyses were performed, and the main effects of time and group, as well as time × group interaction effects, were investigated. In both groups, cortical surface area decreased up to 5% in some regions, and cortical thickness up to 8%, over the five-year period. The most affected regions were located on the lateral aspect of the hemispheres, in posterior temporal, parietal and to some extent frontal regions. There was no significant interaction between time and group for either morphometry variable. In conclusion, cortical thickness decreases from 15 to 20 years of age, in a similar fashion in the clinical and control groups. Moreover, we show for the first time that developmental trajectories of cortical surface area in preterm and term-born adolescents do not diverge during adolescence.
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Mapeamento Encefálico , Córtex Cerebral/crescimento & desenvolvimento , Recém-Nascido de muito Baixo Peso/crescimento & desenvolvimento , Inteligência/fisiologia , Adolescente , Adulto , Córtex Cerebral/patologia , Estudos Transversais , Feminino , Humanos , Recém-Nascido Prematuro , Estudos Longitudinais , Imageamento por Ressonância Magnética/métodos , Masculino , Adulto JovemRESUMO
This paper presents a new initiative in the South-Eastern Health Region of Norway to establish a regional resource center focusing on services for children and adolescents aged 2-18 years with prenatal exposure to alcohol or other drugs. In Norway, the prevalence of fetal alcohol spectrum (FAS) is not known but has been estimated to be between 1 and 2 children per 1000 births, while the prevalence of prenatal exposure to illicit drugs is unknown. The resource center is the first of its kind in Scandinavia and will have three main objectives: (1) provide hospital staff, community health and child welfare personnel, and special educators with information, educational courses, and seminars focused on the identification, diagnosis, and treatment of children with a history of prenatal alcohol/drug exposure; (2) provide specialized health services, such as diagnostic services and intervention planning, for children referred from hospitals in the South-Eastern Health Region of Norway; and (3) initiate multicenter studies focusing on the diagnostic process and evaluation of interventions.
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Children born prematurely with very low birth weight (VLBW: bw ≤ 1500 g) have an increased risk of preterm perinatal brain injury, which may subsequently alter the maturation of the brain, including the cerebral cortex. The aim of study was to assess cortical thickness and surface area in VLBW children compared with term-born controls, and to investigate possible relationships between cortical morphology and Full IQ. In this cross-sectional study, 37 VLBW and 104 term children born between the years 2003-2007 were assessed cognitively at 5-10 years of age, using age appropriate Wechsler tests. The FreeSurfer software was used to obtain estimates of cortical thickness and surface area based on T1-weighted MRI images at 1.5 Tesla. The VLBW children had smaller cortical surface area bilaterally in the frontal, temporal, and parietal lobes. A thicker cortex in the frontal and occipital regions and a thinner cortex in posterior parietal areas were observed in the VLBW group. There were significant differences in Full IQ between groups (VLBW M = 98, SD = 9.71; controls M = 108, SD = 13.57; p < 0.001). There was a positive relationship between IQ and surface area in both groups, albeit significant only in the larger control group. In the VLBW group, reduced IQ was associated with frontal cortical thickening and temporo-parietal thinning. We conclude that cortical deviations are evident in childhood even in VLBW children born in 2003-2007 who have received state of the art medical treatment in the perinatal period and who did not present with focal brain injuries on neonatal ultrasonography. The cortical deviations were associated with reduced cognitive functioning.
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Córtex Cerebral/patologia , Recém-Nascido Prematuro , Recém-Nascido de muito Baixo Peso , Inteligência/fisiologia , Criança , Pré-Escolar , Estudos Transversais , Feminino , Humanos , Recém-Nascido , Imageamento por Ressonância Magnética , MasculinoRESUMO
BACKGROUND: Preterm born very-low-birth-weight (VLBW: birth weight ≤1500 g) survivors have increased risk of perinatal brain injury that may cause deviant brain development and later neuroimpairments, including reduced cognitive functioning. AIMS: In this long-term follow up study of three year-cohorts (birth years 1986-88) of VLBW subjects and term born controls with normal birth weight, the aim was to examine differences in brain volumes at age 20 years. In addition, the relationships between brain volumes and cognitive abilities and perinatal variables were explored. METHODS: Forty-four VLBW subjects and 60 controls were assessed with cognitive testing (Wechsler Adult Intelligence Scale - WAIS-III) and structural MRI at 1.5 T, using the FreeSurfer 5.1 software for volumetric analysis. A subpopulation had MRI performed also at age 15, and for this group changes in brain volumes with age were examined. RESULTS: The VLBW subjects had smaller brain volumes, especially of thalamus, globus pallidus and parts of the corpus callosum, and larger lateral ventricles than controls at age 20. However, no significant group differences in longitudinal change from age 15 to 20 were observed. The most immature and smallest VLBW subjects at birth, and those with the highest perinatal morbidity, showed most pronounced volume deviations. Positive associations between several brain volumes and full IQ, as well as three of four IQ indices in the VLBW group, were observed. CONCLUSION: Reduced volumes of grey and white matter and ventricular dilatation in VLBW young adults may indicate permanent effects on brain development from perinatal brain injury with influence on later cognitive function.
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Encéfalo/anatomia & histologia , Cognição/fisiologia , Lactente Extremamente Prematuro , Adulto , Encéfalo/crescimento & desenvolvimento , Estudos de Coortes , Feminino , Idade Gestacional , Humanos , Processamento de Imagem Assistida por Computador , Recém-Nascido Prematuro , Imageamento por Ressonância Magnética , Masculino , Testes Neuropsicológicos , Escalas de Wechsler , Adulto JovemRESUMO
BACKGROUND: Mild cognitive impairment (MCI) is a condition characterized by memory problems that are more severe than the normal cognitive changes due to aging, but less severe than dementia. Reduced working memory (WM) is regarded as one of the core symptoms of an MCI condition. Recent studies have indicated that WM can be improved through computer-based training. The objective of this study is to evaluate if WM training is effective in improving cognitive function in elderly patients with MCI, and if cognitive training induces structural changes in the white and gray matter of the brain, as assessed by structural MRI. METHODS/DESIGNS: The proposed study is a blinded, randomized, controlled trail that will include 90 elderly patients diagnosed with MCI at a hospital-based memory clinic. The participants will be randomized to either a training program or a placebo version of the program. The intervention is computerized WM training performed for 45 minutes of 25 sessions over 5 weeks. The placebo version is identical in duration but is non-adaptive in the difficulty level of the tasks. Neuropsychological assessment and structural MRI will be performed before and 1 month after training, and at a 5-month folllow-up. DISCUSSION: If computer-based training results in positive changes to memory functions in patients with MCI this may represent a new, cost-effective treatment for MCI. Secondly, evaluation of any training-induced structural changes to gray or white matter will improve the current understanding of the mechanisms behind effective cognitive interventions in patients with MCI. TRIAL REGISTRATION: ClinicalTrials.gov NCT01991405. November 18, 2013.
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Envelhecimento/psicologia , Cognição , Disfunção Cognitiva/terapia , Memória , Projetos de Pesquisa , Terapia Assistida por Computador , Fatores Etários , Protocolos Clínicos , Disfunção Cognitiva/diagnóstico , Disfunção Cognitiva/psicologia , Humanos , Imageamento por Ressonância Magnética , Testes Neuropsicológicos , Noruega , Fatores de Tempo , Resultado do TratamentoRESUMO
BACKGROUND: Extremely-low-birth-weight (ELBW) children without severe brain injury or CP are at high risk of developing deficits within cognition, attention, behavior and motor function. Assessing the quality of an infant's spontaneous motor-repertoire included in Prechtl's General-Movement-Assessment (GMA) has been shown to relate to later motor and cognitive functioning in preterm children without CP. AIMS: To investigate functional outcome and cerebral MRI morphometry at 10 years in ELBW children without CP compared to healthy controls and to examine any relationship with the quality of infant-motor-repertoire included in the GMA. STUDY DESIGN: A cohort-study-design. SUBJECTS: 31 ELBW children (mean birth-weight: 773 g, SD 146, mean gestational age 26.1 weeks, SD 1.8) and 33 term-born, age-matched controls. OUTCOME MEASURES: GMA was performed in ELBW children at 3 months corrected age. At 10 years the children underwent comprehensive motor, cognitive, behavioral assessments and cerebral MRI. RESULTS: The non-CP ELBW children had similar full-IQ but poorer working memory, poorer motor skills, and more attentional and behavioral problems compared to controls. On cerebral MRI reduced volumes of globus pallidus, cerebellar white matter and posterior corpus callosum were found. Cortical surface-area was reduced in temporal, parietal and anterior-medial-frontal areas. Poorer test-results and reduced brain volumes were mainly found in ELBW children with fidgety movements combined with abnormal motor-repertoire in infancy. CONCLUSION: Non-CP ELBW children have poorer functional outcomes, reduced brain volumes and cortical surface-area compared with term-born controls at 10 years. ELBW children with abnormal infant motor-repertoire seem to be at increased risk of later functional deficits and brain pathology.