Cognitive and Emotional Executive Functions in Preschool Children Born Very Low Birth Weight with Normal Early Development

Abstract

SUMMARY The aim of this study was to investigate cognitive and emotional EF profile in VLBW children with normal early development at preschool age Participants were 116 six to seven-year-old VLBW children with normal early development and 58 term children with comparable gender home environment and social economic status Wechsler Intelligence Scale for Children-IV (WISC-IV) Comprehensive Non-verbal Attention Test Battery (CNAT) Tower of London (ToL) Wisconsin Card Sorting Test (WCST) Knox’s Cube Test (KCT) and Emotional EF Ecological Assessment Battery for Children in Taiwan were administered in order to evaluate cognitive EF and emotional EF in the two groups The results showed that VLBW children with normal early development have cognitive EF deficits in working memory cognitive flexibility planning and inhibition and in emotion EF domain they showed weaker delay of gratification and theory of mind In order to investigate the correlation of the two emotion EF deficits which the preterm group performed poorer and cognitive EF further analysis showed that these two groups of children have different pattern in the two EF domains’ relationships; the two domains’ significant correlations are fewer in the preterm group whereas the term group showed stronger correlations in the two EF domains In conclusion this study revealed that VLBW children with normal early development have deficits in both cognitive and emotional EF and the discrepancy between the two EF domains might indicate the immaturity of the preterm children’s brain it may be helpful for clinicians to intervene these preterm children in advance Key words: Preterm Very low birth weight Executive function Emotional executive function INTRODUCTION Based on World Health Organization (WHO)’s definition preterm children are defined as being born before 37 weeks’ gestation The survival rates of preterm infants have increased due to the improvements in recent neonatal care However the prevalence of neurodevelopmental sequelae do not decrease in this group which means that more preterm children face challenges in the future Children born prematurely are at high risk of developmental delay or executive dysfunction especially those with lower birthweight Ni Huang and Guo (2011) further excluded the influence of early development delay and revealed that preschool preterm children with normal early development have poorer EF compared to normal full-term children In other words the probabilities of EF deficits are still high in those who develop normally in their early years and the difficulties may gradually emerge as they grow up The results implied that preterm children with normal early development still require clinical attention Previous studies primarily focused on the cognitive aspect of EF without considering the emotional aspect Recently a distinction has been made between “cognitive EF” and “emotional EF” in the theoretical and empirical literature Hence the evaluation of emotional EF is necessary in order to fully understand the whole picture of EF in preterm children The aim of this study was to investigate whether the very-low-birth-weight (VLBW; born less than 1500 g) children with normal early development have deficits in emotional EF at preschool age MATERIALS AND METHODS The study was conducted in two groups The VLBW group was referred from Premature Baby Foundation of Taiwan These children have been followed up and the Bayley Scales of Infant Development II/III (BSID-II and Bayley-III) was administered at the age of 12 months and 24months as well as Wechsler Preschool and Primary Scale of Intelligence-Revised (WPPSI-R) was administered at the age of 5 Children with visual impairment auditory impairment cerebral palsy developmental indices of BSID-II/III less than 70 or full-scale IQ (FSIQ) of WPPSI-R less than 70 were excluded At last the VLBW group comprised 116 six to seven-year-old VLBW children with normal early development The comparison group comprised 58 term children with comparable gender home environment and social economic status from local schools who volunteered to participate in the study Multiple EF assessment tools were administered at the age of 6 Cognitive EF including inhibition working memory planning and cognitive flexibility were assessed by Comprehensive Nonverbal Attention Test Battery (CNAT) Tower of London (ToL) Wisconsin Card Sorting Test (WCST) Knox's Cube Test (KCT) and Digit Span Subtest of WISC-IV We designed Emotional EF Ecological Assessment Battery for Children in Taiwan to assess Emotional EF including delay of gratification emotion regulation and theory of mind Independent t-test and Chi-square were used to analyze the differences between groups with the significant level at 05 Also Cohen’d was calculated to evaluate the effect size RESULTS AND DISCUSSION The results showed that VLBW children with normal early development have cognitive EF deficits in working memory cognitive flexibility planning and inhibition and in emotion EF domain they showed weaker delay of gratification and theory of mind In order to investigate the correlation of the two emotion EF deficits which the preterm group performed poorer and cognitive EF further analysis showed that these two groups of children have different pattern in the two EF domains’ relationships; the two domains’ significant correlations are fewer in the preterm group whereas the term group showed stronger correlations in the two EF domains CONCLUSION The results of this study suggested that even if the VLBW children are normal in early cognitive development they might have deficits in both cognitive and emotional EF at preschool age and the discrepancy between the two EF domains indicates the immaturity of the preterm children’s brain it may be helpful for clinicians to intervene these preterm children in advance Further empirical data might be necessary to establish a more comprehensive model for clinical psychological assessment and intervention in preterm children

Date of Award	2019
Original language	English
Supervisor	Nai-Wen Guo (Supervisor)