OBJECTIVE Although preterm very low birth weight infants have a high prevalence of neuroanatomical abnormalities when evaluated at term-equivalent age, patterns of brain growth in prematurely born infants during school age and adolescence remain largely unknown. Our goal was to test the hypothesis that preterm birth results in long-term dynamic changes in the developing brain. METHODS We performed serial volumetric MRI studies at ages 8 and 12 years in 55 preterm infants born weighing 600 to 1250 g and 20 term control children who participated in the follow-up component of a prospective, randomized, placebo-controlled intraventricular hemorrhage prevention study. RESULTS Total brain volumes increased 2% to 3% between the ages of 8 and 12 years for both preterm and term children. These changes involved reductions in cerebral gray matter while white matter increased. Between 8 and 12 years of age, preterm subjects experienced a 2% decrease in left cerebral gray matter compared with a 10% reduction in left cerebral gray for term controls. For right cerebral gray matter, preterm children experienced a 3% decrease in volume between years 8 and 12, compared with 9% for term controls (group-by-time). In contrast, preterm subjects had a 10% increase in cerebral white matter volumes bilaterally between ages 8 and 12 years, compared with >26% increases for both hemispheres for term controls. Significant differences in regional volume changes between study groups were found in bilateral temporal gray and in parietal white matter. CONCLUSIONS Preterm birth continues to perturb the trajectory of cerebral development during late childhood and early adolescence with preterm children, showing both lower gray matter reduction and less white matter gain over time compared with term control subjects.

OBJECTIVETo determine if frequent exposures to hypoglycemia and hyperglycemia during early childhood lead to neurocognitive deficits and changes in brain anatomy.RESEARCH DESIGN AND METHODSIn this feasibility, cross-sectional study, young children, aged 3 to 10 years, with type 1 diabetes and age- and sex-matched healthy control (HC) subjects completed neuropsychologic (NP) testing and magnetic resonance imaging (MRI) scans of the brain.RESULTSNP testing and MRI scanning was successfully completed in 98% of the type 1 diabetic and 93% of the HC children. A significant negative relationship between HbA1c and Wechsler Intelligence Scale for Children (WISC) verbal comprehension was observed. WISC index scores were significantly reduced in type 1 diabetic subjects who had experienced seizures. White matter volume did not show the expected increase with age in children with type 1 diabetes compared with HC children (diagnosis by age interaction, P = 0.005). A similar trend was detected for hippocampal volume. Children with type 1 diabetes who had experienced seizures showed significantly reduced gray matter and white matter volumes relative to children with type 1 diabetes who had not experienced seizures.CONCLUSIONSIt is feasible to perform MRI and NP testing in young children with type 1 diabetes. Further, early signs of neuroanatomic variation may be present in this population. Larger cross-sectional and longitudinal studies of neurocognitive function and neuroanatomy are needed to define the effect of type 1 diabetes on the developing brain.

We assessed visual short-term memory (VSTM) for color in 6- and 8-month-old infants (n = 76) using a one-shot change detection task. In this task, a sample array of two colored squares was visible for 517 ms, followed by a 317-ms retention period and then a 3000-ms test array consisting of one unchanged item and one item in a new color. We tracked gaze at 60 Hz while infants looked at the changed and unchanged items during test. When the two sample items were different colors (Experiment 1), 8-month-old infants exhibited a preference for the changed item, indicating memory for the colors, but 6-month-olds exhibited no evidence of memory. When the two sample items were the same color and did not need to be encoded as separate objects (Experiment 2), 6-month-old infants demonstrated memory. These results show that infants can encode information in VSTM in a single, brief exposure that simulates the timing of a single fixation period in natural scene viewing, and they reveal rapid developmental changes between 6 and 8 months in the ability to store individuated items in VSTM.

BackgroundFragile X syndrome (FXS) is the most common cause of inherited intellectual disability and non-idiopathic autism. Individuals with FXS present with a behavioral phenotype of specific and selective deficits in an array of cognitive skills. Disruption of number processing and arithmetic abilities in higher-functioning adults and female adolescents with FXS has been well established. Still, both numerical skills and developmentally antecedent cognitive processes have just begun to be investigated in toddlers with FXS. The goal of the current study was to assess how very young children with FXS respond to ordinal relationships among numerical magnitudes.MethodsInfrared eye-tracking was used to explore infants’ novelty recognition during passive viewing of ordinal numerical sequences; t-tests were used to analyze group differences in looking time.ResultsOrdinal recognition of numerical magnitudes is significantly impaired in young toddlers with FXS.ConclusionsThis study is the first to experimentally evaluate early number sense and ordinal recognition in toddlers with FXS, and our findings reveal that ordinal recognition of numerical magnitudes is significantly impaired in young toddlers with FXS, suggesting that later arithmetic impairments associated with FXS may have their origins in a developmental impairment of this more basic aspect of numerical cognition.

When learning object function, infants must detect relations among featuresfor example, that squeezing is associated with squeaking or that objects with wheels roll. Previously, Perone and Oakes (2006) found 10-month-old infants were sensitive to relations between object appearances and actions, but not to relations between appearances and sounds or actions and sounds. In this article the authors probed the development of infants' attention to feature correlations critical for representing function by testing 8-and 12-month-old infants' (N ¼ 126) sensitivity to such relations. Eight-month-old infants learned individual features but were not sensitive to the relations between those features. Twelve-month-old infants were sensitive to the relation among the features and significantly responded to violations in learned relations between object appearances and actions and between appearances and sounds. Thus, across development, infants become sensitive to an increasing number of relations with age, supporting an information-processing account of the development of object function.Understanding the function of objects is important for learning how to act on and categorize objects. Function is considered central to infants' conceptual development (Keil, 1989;Nelson, 1973Nelson, , 1974Nelson, , 1979), yet there is no standard definition for function in the field of psychological research.Correspondence should be sent to Lisa M. Oakes