Search

Executive function (EF) refers to fundamental capacities that underlie more complex cognition and have ecological relevance across the individual's lifespan. However, emerging executive functions have rarely been studied in young preterm children (age 3) whose critical final stages of fetal development are interrupted by their early birth. We administered four novel touch-screen computerized measures of working memory and inhibition to 369 participants born between 2004 and 2006 (52 Extremely Low Birth Weight [ELBW]; 196 late preterm; 121 term-born). ELBW performed worse than term-born on simple and complex working memory and inhibition tasks and had the highest percentage of incomplete performance on a continuous performance test. The latter finding indicates developmental immaturity and the ELBW group's most at-risk preterm status. Additionally, late-preterm participants performed worse compared with term-born on measures of complex working memory but did not differ from those term-born on response inhibition measures. These results are consistent with a recent literature that identifies often subtle but detectable neurocognitive deficits in late-preterm children. Our results support the development and standardization of computerized touch-screen measures to assess EF subcomponent abilities during the formative preschool period. Such measures may be useful to monitor the developmental trajectory of critical executive function abilities in preterm children, and their use is necessary for timely recognition of deficit and application of appropriate interventional strategies. [ABSTRACT FROM AUTHOR]

Spatial location memory has rarely been assessed in young children due to a scarcity of developmentally appropriate tests. This study sought to compare nonverbal learning and recall in children born extremely low birth weight (ELBW; <1000 g) and less than 33 gestational weeks (GW) with term-born children at early school age using a recently developed and adapted test. We administered a modification of the Hopkins Board to 210 children at age six; 84 born ELBW (35 born < 26 GW; 49 born 26–33 GW) and 126 term-born. Six measures were obtained: naming, trials-to-criterion, errors-to-criterion, delayed item recall, delayed location recall, and percent retention. After age correction, ELBW children had worse general cognition, item naming, delayed item recall, delayed location recall, and percent retention than term-born children. Delayed item recall and percent retention performances of ELBW children remained worse after correction for general cognition. ELBW groups (< 26 GW and 26–33 GW) groups performed worse than term-born children in naming and delayed item recall with chronological age as covariate. Those born before 26 GW, but not 26–33 GW, performed worse than term-born children in delayed location recall and percent retention. Differences remained significant after controlling for gender, maternal education, and delivery type. All three groups' performance declined from final learning trial to delayed location recall, with a decline greater for less than 26 GW than term-born children. Extreme prematurity (< 26 GW) and ELBW are significant risk factors for spatial location memory deficit. The modified Hopkins Board discriminated high-risk preterm and term-born children at early school age and appears to be a useful test to measure this rarely studied cognitive capacity. [ABSTRACT FROM AUTHOR]

Preterm (PT) birth is an established risk factor for high mortality and morbidity rates. Infants and school-aged children have been well-studied, but few have described neuropsychological and behavioral outcomes at preschool age. We compared a 2004-2006 preterm/extremely low birth weight (ELBW) cohort (PT/ELBW; N = 60) born ≤33 weeks gestation and <1,000 g with term-born participants (N = 90) at age 3. PT/ELBW subgroups (<26 weeks; 26-33 weeks) performed more poorly than the term-born group on verbal, nonverbal, fine motor, visual-motor, visual attention, noun fluency, early number concepts, and functional communication measures prior to age correction; PT/ELBW children born <26 weeks additionally performed more poorly on action-verb fluency. Those born 26-33 weeks had executive and adaptive deficits on parental behavioral report. Age correction significantly improved preterm scores without masking relative verbal, nonverbal, motor, and behavioral weaknesses that may require early intervention. In conclusion, subtle delays in emergent neuropsychological and behavioral functions are measurable at age 3, and neurobiological immaturity remains a prepotent influence on outcome in the preschool years. Further study should enhance our understanding of the trajectory of brain development and the limits of neuroplasticity in these highly at-risk children. [ABSTRACT FROM AUTHOR]