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Objectives: The developmental absence (agenesis) of the corpus callosum (AgCC) is a congenital brain malformation associated with risk for a range of neuropsychological difficulties. Inhibitory control outcomes, including interference control and response inhibition, in children with AgCC are unclear. This study examined interference control and response inhibition: 1) in children with AgCC compared with typically developing (TD) children, 2) in children with different anatomical features of AgCC (complete vs. partial, isolated vs. complex), and 3) associations with white matter volume and microstructure of the anterior (AC) and posterior commissures (PC) and any remnant corpus callosum (CC). Methods: Participants were 27 children with AgCC and 32 TD children 8–16 years who completed inhibitory control assessments and brain MRI to define AgCC anatomical features and measure white matter volume and microstructure. Results: The AgCC cohort had poorer performance and higher rates of below average performance on inhibitory control measures than TD children. Children with complex AgCC had poorer response inhibition performance than children with isolated AgCC. While not statistically significant, there were select medium to large effect sizes for better inhibitory control associated with greater volume and microstructure of the AC and PC, and with reduced volume and microstructure of the remnant CC in partial AgCC. Conclusions: This study provides evidence of inhibitory control difficulties in children with AgCC. While the sample was small, the study found preliminary evidence that the AC (f 2=.18) and PC (f 2=.30) may play a compensatory role for inhibitory control outcomes in the absence of the CC. [ABSTRACT FROM AUTHOR]

Objectives: Children born very preterm (VP) are susceptible to a range of cognitive impairments, yet the effects of VP birth on long-term, episodic, and prospective memory remains unclear. This study examined episodic and prospective memory functioning in children born VP compared with their term-born counterparts at 13 years. Method: VP (n = 81: born <30 weeks' gestation) and term (n = 26) groups were aged between 12 and 14 years. Children completed: (i) standardized verbal and visuospatial episodic memory tests; and (ii) an experimental time- and event-based prospective memory test that included short-term (within assessment session) and long-term (up to 1-week post-session) tasks. Parents completed a questionnaire assessing memory functions in everyday life. Results: The VP group performed worse on all measures of verbal and visuospatial episodic memory than the term group. While there were no group differences in event-based or long-term prospective memory, the VP group performed worse on time-based and short-term prospective memory tasks than term-born counterparts. Parents of children born VP reported more everyday memory difficulties than parents of children born at term, with parent-ratings indicating significantly elevated rates of everyday memory challenges in children born VP. Conclusions: Children born VP warrant long-term surveillance, as challenges associated with VP birth include memory difficulties at 13 years. This study highlights the need for greater research and clinical attention into childhood functional memory outcomes. [ABSTRACT FROM AUTHOR]

This study in children born extremely preterm (EP; <28 weeks' gestational age) or extremely low birth weight (ELBW; <1,000 g) investigated whether adaptive working memory training using Cogmed® is associated with structural and/or functional brain changes compared with a placebo program. Ninety‐one EP/ELBW children were recruited at a mean (standard deviation) age of 7.8 (0.4) years. Children were randomly allocated to Cogmed or placebo (45‐min sessions, 5 days a week over 5–7 weeks). A subset had usable magnetic resonance imaging (MRI) data pretraining and 2 weeks posttraining (structural, n = 48; diffusion, n = 43; task‐based functional, n = 18). Statistical analyses examined whether cortical morphometry, white matter microstructure and blood oxygenation level‐dependent (BOLD) signal during an n‐back working memory task changed from pretraining to posttraining in the Cogmed and placebo groups separately. Interaction analyses between time point and group were then performed. There was a significant increase in neurite density in several white matter regions from pretraining to posttraining in both the Cogmed and placebo groups. BOLD signal in the posterior cingulate and precuneus cortices during the n‐back task increased from pretraining to posttraining in the Cogmed but not placebo group. Evidence for group‐by‐time interactions for the MRI measures was weak, suggesting that brain changes generally did not differ between Cogmed and placebo groups. Overall, while some structural and functional MRI changes between the pretraining and posttraining period in EP/ELBW children were observed, there was little evidence of training‐induced neuroplasticity, with changes generally identified in both groups. Trial registration Australian New Zealand Clinical Trials Registry, anzctr.org.au; ACTRN12612000124831. [ABSTRACT FROM AUTHOR]

Objectives: Preterm children demonstrate deficits in executive functions including inhibition, working memory, and cognitive flexibility; however, their goal setting abilities (planning, organization, strategic reasoning) remain unclear. This study compared goal setting abilities between very preterm (VP: <30 weeks/<1250 grams) and term born controls during late childhood. Additionally, early risk factors (neonatal brain abnormalities, medical complications, and sex) were examined in relationship to goal setting outcomes within the VP group. Methods: Participants included 177 VP and 61 full-term born control children aged 13 years. Goal setting was assessed using several measures of planning, organization, and strategic reasoning. Parents also completed the Behavior Rating Inventory of Executive Function. Regression models were performed to compare groups, with secondary analyses adjusting for potential confounders (sex and social risk), and excluding children with major neurosensory impairment and/or IQ<70. Within the VP group, regression models were performed to examine the relationship between brain abnormalities, medical complications, and sex, on goal setting scores. Results: The VP group demonstrated a clear pattern of impairment and inefficiency across goal setting measures, consistent with parental report, compared with their full-term born peers. Within the VP group, moderate/severe brain abnormalities on neonatal MRI predicted adverse goal setting outcomes at 13. Conclusions: Goal setting difficulties are a significant area of concern in VP children during late childhood. These difficulties are associated with neonatal brain abnormalities, and are likely to have functional consequences academically, socially and vocationally. (JINS, 2018, 24, 372–381) [ABSTRACT FROM AUTHOR]

Child stroke is a major cause of death in children, although limited information exists on neurobehavioral functioning of stroke survivors. Executive function (important for goal-directed behavior) is thought to be vulnerable to early insults such as stroke because of its widespread representation in the immature brain. This study investigated the impact of lesion location on executive skills. Twenty-eight children diagnosed with stroke at least 18 months before assessment were recruited. Lesion characteristics were coded from magnetic resonance imaging (MRI) scans. Neurobehavioral assessment focused on cognitive and everyday executive skills. Deficits were found in the context of overall normal intellectual functioning (M = 91.60; SD = 19.40). Generally, insults involving frontal and extra-frontal regions impacted equally on cognitive performance. Everyday deficits were marginally more prominent following frontal insult. Subcortical frontal lesions were associated with impairments in everyday executive skills. Results provide further support for the diffuse representation of executive function in the immature brain. [ABSTRACT FROM AUTHOR]

Attention and social functioning and their interrelationships have not been routinely examined in children with early brain insult (EBI). This study aimed to describe attention and social functioning in children with two types of EBI: malformations of cortical development (MCD) and stroke. Children diagnosed with MCD (n = 14, 6 males) or stroke (n = 14, 8 males) aged 8 to 14 years (M = 12 years 11 months) completed neuropsychological assessments to examine attention processes. Primary caregivers completed a questionnaire to assess executive components of children's attention and teachers completed a questionnaire to measure children's social functioning. Brain scans (MRI or CT) were coded by a pediatric neuroradiologist. Higher rates of impairments in attention and social function were found in children with EBI compared with normative expectations. Children with MCD experienced more global and clinically significant levels of impairment than children with stroke; though impairments were present in both groups. A strong association between executive components of attention and social function was observed. In addition, complex attention processes were associated with social function. The findings emphasize the reciprocity between attention, behavior and social outcomes, and the vulnerability of social function following EBI.

The aim of this study was to examine attention in a large, representative, contemporary cohort of children born extremely preterm (EP) and/or extremely low birth weight (ELBW). Participants included 189 of 201 surviving children born EP (<28 weeks' gestation) or ELBW (<1,000 g) in 1997 in the state of Victoria, Australia. A comparison group of 173 of 199 children born full term and normal birth weight (FT/NBW) were randomly selected matching for birth hospital, expected due date, gender, mother's country of birth, and health insurance status. Participants were assessed at 8 years of age on subtests from the Test of Everyday Attention for Children (TEA-Ch) and the Wechsler Intelligence Scale for Children-4th Edition (WISC-IV). Measures of selective attention, sustained attention, attention encoding, and executive attention (inhibition, shifting attention, and divided attention) were administered. To assess behavioral elements of inattention, the primary caregiver completed the Behavior Rating Inventory of Executive Function (BRIEF) and the Conners' ADHD/DSM-IV Scale (CADS-P). The EP/ELBW group performed more poorly across all cognitive and behavioral measures than the FT/NBW group, with the exception of inhibition. The EP/ELBW group also had significantly elevated rates of impairment in selective, sustained, shifting and divided attention, as well as attention deficit hyperactivity disorder (ADHD) symptoms. No significant gender or gradient effects (e.g., <26 weeks' gestation vs. ≥ 26 weeks' gestation) were identified. Neonatal medical factors were not strong predictors of attention, although necrotizing enterocolitis (NEC) and cystic periventricular leukomalacia (PVL) were independent predictors of selective attention. In conclusion, our comprehensive assessment of attention provides strong evidence that children born EP/ELBW are at increased risk for attentional impairments, and as such, this population should be monitored closely during early and middle childhood with a focus on attention functioning.

Social dysfunction is commonly reported by survivors of brain insult, and is often rated as the most debilitating of all sequelae, impacting on many areas of daily life, as well as overall quality of life. Within the early brain insult (EBI) literature, physical and cognitive domains have been of primary interest and social skills have received scant attention. As a result it remains unclear how common these problems are, and whether factors predictive of recovery (insult severity, lesion location, age at insult, environment) in other functional domains (motor, speech, cognition) also contribute to social outcome. This study compared social outcomes for children sustaining EBI at different times from gestation to late childhood to determine whether EBI was associated with an increased risk of problems. Children with focal brain insults were categorized according to timing of brain insult: (i) Congenital (n = 38): EBI: first-second trimester; (ii) Perinatal (n = 33); EBI: third trimester to 1-month post-natal; (iii) Infancy (n = 23): EBI: 2 months-2 years post-birth; (iv) Preschool (n = 19): EBI: 3-6 years; (v) Middle Childhood (n = 31): EBI: 7-9 years; and (vi) Late Childhood (n = 19): EBI: after age 10. Children's teachers completed questionnaires measuring social function (Strengths and Difficulties Questionnaire, Walker-McConnell Scale of Social Competence and School Adjustment). Results showed that children with EBI were at increased risk for social impairment compared to normative expectations. EBI before age 2 years was associated with most significant social impairment, while children with EBI in the preschool years and in late childhood recorded scores closer to normal. Lesion location and laterality were not predictive of social outcome, and nor was social risk. In contrast, presence of disability (seizures) and family function were shown to contribute to aspects of social function.