The forest, the trees, and the leaves in preterm children: the impact of prematurity on a visual search task containing three-level hierarchical stimuli

Effects of general anaesthesia in early childhood on local and global visual processing: a post hoc analysis of the APEX cohort study

BACKGROUND

Preclinical studies suggest that early exposure to anaesthesia alters the visual system in mice and non-human primates. We investigated whether exposure to general anaesthesia leads to visual attention processing changes in children, which could potentially impact essential life skills, including learning.

METHODS

This was a post hoc analysis of data from the APprentissages EXécutifs et cerveau chez les enfants d'âge scolaire (APEX) cohort study. A total of 24 healthy 9-10-yr-old children who were or were not exposed to general anaesthesia (for surgery) by a mean age of 3.8 (2.6) yr performed a visual attention task to evaluate ability to process either local details or general global visual information. Whether children were distracted by visual interference during global and local information processing was also assessed.

RESULTS

Participants included in the analyses (n=12 participants exposed to general anaesthesia and n=12 controls) successfully completed (>90% of correct answers) the trial tasks. Children from both groups were equally distracted by visual interference. However, children who had been exposed to general anaesthesia were more attracted to global visual information than were control children (P=0.03).

CONCLUSIONS

These findings suggest lasting effects of early-life exposure to general anaesthesia on visuospatial abilities. Further investigations of the mechanisms by which general anaesthesia could have delayed effects on how children perceive their visual environment are needed.

Cognitive Training for Visuospatial Processing in Children Aged 5½ to 6 Years Born Very Preterm With Working Memory Dysfunction: A Randomized Clinical Trial

Importance

Compared with term-born peers, children born very preterm generally perform poorly in executive functions, particularly in working memory and inhibition. By taking advantage of neuroplasticity, computerized cognitive training of working memory in those children could improve visuospatial processing by boosting visual inhibition via working memory.

Objective

To evaluate the long-term effect of cognitive working memory training on visuospatial processing in children aged 5½ to 6 years born very preterm who have working memory impairment.

Design, Setting, and Participants

This multicenter (18 French university hospitals), open-label randomized clinical trial with 2 parallel groups (EPIREMED) was conducted from November 2016 to April 2018, with the last follow-up during August 2019. Eligible children from the EPIPAGE 2 cohort were aged 5½ to 6 years, were born between 24 and 34 weeks' gestation, and had a global intelligence quotient greater than 70 and a working memory index less than 85. Data were analyzed from February to December 2020.

Intervention

Children were randomized 1:1 to standard care management and a working memory cognitive training program (Cogmed software) for 8 weeks (25 sessions) (intervention) or to standard management (control).

Main Outcomes and Measures

The primary outcome was the visuospatial index score from the Wechsler Preschool and Primary Scale of Intelligence, 4th Edition. Secondary outcomes were working memory, intellectual functioning, executive and attention processes, language skills, behavior, quality of life, and schooling. Neurobehavioral assessments were performed at inclusion and after finishing training at 6 months (intermeditate assessment; secondary outcomes) and at 16 months (final assessment; primary outcome).

Results

There were 169 children randomized, with a mean (SD) age of 5 years 11 months (2 months); 91 (54%) were female. Of the participants, 84 were in the intervention group (57 of whom [68%] completed at least 15 cognitive training sessions) and 85 were in the control group. The posttraining visuospatial index score was not different between groups at a mean (SD) of 3.0 (1.8) months (difference, -0.6 points; 95% CI, -4.7 to 3.5 points) or 12.9 (2.6) months (difference, 0.1 points; 95% CI, -5.4 to 5.1 points). The working memory index score in the intervention group significantly improved from baseline at the intermediate time point (difference, 4.7 points; 95% CI, 1.2-8.1 points), but this improvement was not maintained at the final assessment.

Conclusions and Relevance

This randomized clinical trial found no lasting effect of a cognitive training program on visuospatial processing in children aged 5½ to 6 years with working memory disorders who were born very preterm. The findings suggest that this training has limited long-term benefits for improving executive function. Transient benefits seemed to be associated with the developmental state of executive functions.

Trial Registration

ClinicalTrials.gov Identifier: NCT02757794.

Neurobehavioral Phenotype and Dysexecutive Syndrome of Preterm Children: Comorbidity or Trigger? An Update

Premature birth is a worldwide public health priority. One in ten children is born before 37 weeks of gestational age and, in developed countries, survival rates without major neonatal morbidity are increasing. Although severe sequelae associated with these births have decreased, their neurobehavioral difficulties, often associated in multiple fields, remain stable but still widespread. These neurobehavioral difficulties hamper the normal development of academic achievements and societal integration and intensify the children's needs for rehabilitation during their preschool and academic years. Severe sequelae increase when gestational age decreases. This is even truer if the socio-cultural background is impeded by low income, education and language skills as compared with defined averages. However, moderate and/or minor neurocognitive and/or behavioral difficulties are almost identical for a moderate or a late preterm birth. Obtaining a better clinical description of neurobehavioral characteristics of those pretermly born, once they reach preschool age, is essential to detect behavioral issues as well as early specific cognitive difficulties (working memory, planning, inhibition, language expression and reception, attention and fine motor skills, etc.). Such information would provide a better understanding of the executive functions' role in brain connectivity, neurodevelopment and neuroanatomical correlation with premature encephalopathy.

Individual Attention Patterns in Children Born Very Preterm and Full Term at 7 and 13 Years of Age

OBJECTIVE

To identify attention profiles at 7 and 13 years, and transitions in attention profiles over time in children born very preterm (VP; <30 weeks' gestation) and full term (FT), and examine predictors of attention profiles and transitions.

METHODS

Participants were 167 VP and 60 FT children, evaluated on profiles across five attention domains (selective, shifting and divided attention, processing speed, and behavioral attention) at 7 and 13 years using latent profile analyses. Transitions in profiles were assessed with contingency tables. For VP children, biological and social risk factors were tested as predictors with a multinomial logistic regression.

RESULTS

At 7 and 13 years, three distinct profiles of attentional functioning were identified. VP children were 2-3 times more likely to show poorer attention profiles compared with FT children. Transition patterns between 7 and 13 years were stable average, stable low, improving, and declining attention. VP children were two times less likely to have a stable average attention pattern and three times more likely to have stable low or improving attention patterns compared with FT children. Groups did not differ in declining attention patterns. For VP children, brain abnormalities on neonatal MRI and greater social risk at 7 years predicted stable low or changing attention patterns over time.

CONCLUSIONS

VP children show greater variability in attention profiles and transition patterns than FT children, with almost half of the VP children showing adverse attention patterns over time. Early brain pathology and social environment are markers for attentional functioning.

How a picture becomes a word: individual differences in the development of language-mediated visual search

Over the course of our lifetimes, we accumulate extensive experience associating the things that we see with the words we have learned to describe them. As a result, adults engaged in a visual search task will often look at items with labels that share phonological features with the target object, demonstrating that language can become activated even in non-linguistic contexts. This highly interactive cognitive system is the culmination of our linguistic and visual experiences-and yet, our understanding of how the relationship between language and vision develops remains limited. The present study explores the developmental trajectory of language-mediated visual search by examining whether children can be distracted by linguistic competitors during a non-linguistic visual search task. Though less robust compared to what has been previously observed with adults, we find evidence of phonological competition in children as young as 8 years old. Furthermore, the extent of language activation is predicted by individual differences in linguistic, visual, and domain-general cognitive abilities, with the greatest phonological competition observed among children with strong language abilities combined with weaker visual memory and inhibitory control. We propose that linguistic expertise is fundamental to the development of language-mediated visual search, but that the rate and degree of automatic language activation depends on interactions among a broader network of cognitive abilities.