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Compromised approximate number system acuity in extremely preterm school-aged children
Kerstin Hellgren1, Justin Halberda, Lea Forsman
1Department of Clinical Neuroscience, The Karolinska Institute, Stockholm, Sweden; Center of Neurodevelopmental Disorders, The Karolinska Institute, Stockholm, Sweden.
Insights
Children born extremely preterm show poorer approximate number system acuity compared to typically developing peers. This suggests preterm birth negatively impacts early numerical cognition, potentially affecting future math skills.
Area of Science:
- Developmental psychology
- Cognitive neuroscience
- Pediatric research
Background:
- Children born extremely preterm often experience developmental challenges.
- Approximate number system (ANS) acuity is crucial for mathematical development.
- Understanding ANS in preterm infants can inform early interventions.
Purpose of the Study:
- To compare ANS acuity in extremely preterm children and typically developing peers at age 6.5 years.
- To investigate the impact of preterm birth on numerical estimation abilities.
Main Methods:
- A population-based follow-up study included 65 extremely preterm children and 47 typically developing controls.
- Cognitive tests assessed ANS acuity using a computerized task (Weber fraction, response time).
- General cognition, working memory, processing speed, and visual attention were also evaluated.
Main Results:
- Extremely preterm children demonstrated significantly worse ANS acuity (higher Weber fraction) compared to controls.
- Preterm children were also significantly slower in responding to numerical stimuli.
- These differences persisted after adjusting for other cognitive functions.
Conclusions:
- Extremely preterm birth negatively impacts the ability to rapidly approximate and compare numbers.
- This numerical deficiency may stem from dorsal stream dysfunction.
- Further research is needed to link this ANS deficit to mathematical proficiency in preterm children.
Aim:
The aim of this study was to compare the approximate number system acuity in children born extremely preterm aged 6 years 6 months and typically developing, age-matched peers.
Method:
This population-based follow-up study included 65 children born before 27 gestational weeks (35 males, 30 females; mean gestational age 25.4 wks [SD 1.1 wk]; mean birthweight 789 g [SD 158 g]) and 47 typically developing children (24 females, 23 males) at the age of 6 years 6 months. A battery of cognitive tests was administered, including a computerized test for measuring approximate number system acuity and tests for general cognition, working memory, processing speed, and visual attention. Approximate number system outcome measures were means of Weber fraction (w) values and response time in milliseconds.
Results:
The 43 extremely preterm children in whom usable data were obtained performed significantly worse than the typically developing children on the approximate number system task (w=0.30 [SD 0.23] vs. 0.17 [SD 0.13]; p=0.003) and were significantly slower (response time=2934 ms [SD 1102 ms] vs 2376 ms [SD 310 ms]; p=0.002). The differences remained when adjusting for differences in other cognitive functions (p=0.03).
Interpretation:
Preterm birth has a negative impact on an individual's ability to rapidly approximate and compare numbers of visually presented items. This deficiency is thought to be a consequence of dorsal stream dysfunction. Future studies will investigate whether this deficiency is correlated with lower mathematical proficiency in this group of children.
