Segmental Brain Volumes and Cognitive and Perceptual Correlates in 15-Year-Old Adolescents with Low Birth Weight

Abstract

Objective The aim of this study was to examine whether preterm very low birth weight (VLBW) or term born small for gestational age (SGA) adolescents have a reduced regional brain volume. Furthermore, we examined what perinatal factors are related to reduced brain volume in VLBW adolescents, and which regional brain volumes are associated with cognitive and perceptual functioning, and if these differ between the groups. Study design Fifty adolescent preterm VLBW (≤1500g) births and 49 term SGA births (birth weight < 10th percentile) were compared with 57 normal weight term births. An automated MRI segmentation technique was used. Cognitive and perceptual functions were evaluated by WISC-III and Visual Motor Integration (VMI) tests. Results The VLBW group had a reduced volume of thalamus and cerebellar white matter (P<0.002). The SGA group had a smaller total brain, and proportionally smaller regional brain volume. Cerebellar white matter in the VLBW, hippocampus in the SGA, and cerebral cortical in the control group were volumes which significantly predicted cognitive and perceptual functions. Conclusions We speculate that white matter injury may explain the impaired cognitive and perceptual functioning in the prematurely born, whereas hippocampal injury may be related to cognitive dysfunction in term SGA adolescents.

Total brain white matter is a major determinant of IQ in adolescents born preterm

“…14 Our study found that global WM volume and CC area were also good predictors of IQ for the 7 SGA children in this sample. Importantly, our data raise the possibility that the relationship between WM and IQ is different in termborn and preterm brains, because correlations were undetectable in term-born controls, despite a comparable IQ range.…”

Cognitive performance of low- and normal-birth-weight piglets in a spatial hole-board discrimination task

“…In some developing countries 16-50% of term infants are SGA, and the poor home environment in many of the countries adds to the risk of suboptimal development in these children (2). Various studies in humans have shown that being born underweight is a risk factor for cognitive deficits (3)(4)(5)(6)(7)(8), learning problems (4,9), spatial orientation difficulties (10), attention problems (9), depression (11), reduced brain volume (8), and reduced academic achievement and professional attainment (12) later in life.…”

“…It has been reported that the hippocampus is a significant predictor of cognitive functioning in human adolescents who were born SGA (8). The cognitive hole-board task is a hippocampusdependent task (22).…”

Extremely Preterm Birth Outcome: A Review of Four Decades of Cognitive Research

“…The consequences of diffuse white matter degradation also involve cortical, basal ganglia, and cerebellar abnormalities (Counsell et al 2003;Kesler et al 2006). Notably, white matter injury appears to be the most common brain abnormality in preterm infants, and a major predictor of smaller volumes along with gestational age (Martinussen et al 2009). …”