Myelination is associated with processing speed in early childhood:preliminary insights

Processing speed is an important contributor to working memory performance and fluid intelligence in young children. Myelinated white matter plays a central role in brain messaging, and likely mediates processing speed, but little is known about the relationship between myelination and processing speed in young children. In the present study, processing speed was measured through inspection times, and myelin volume fraction (VFM) was quantified using a multicomponent magnetic resonance imaging (MRI) approach in 2- to 5-years of age. Both inspection times and VFM were found to increase with age. Greater VFM in the right and left occipital lobes, the body of the corpus callosum, and the right cerebellum was significantly associated with shorter inspection times, after controlling for age. A hierarchical regression showed that VFM in the left occipital lobe predicted inspection times over and beyond the effects of age and the VFM in the other brain regions. These findings are consistent with the hypothesis that myelin supports processing speed in early childhood

Myelination Is Associated with Processing Speed in Early Childhood: Preliminary Insights.

Processing speed is an important contributor to working memory performance and fluid intelligence in young children. Myelinated white matter plays a central role in brain messaging, and likely mediates processing speed, but little is known about the relationship between myelination and processing speed in young children. In the present study, processing speed was measured through inspection times, and myelin volume fraction (VFM) was quantified using a multicomponent magnetic resonance imaging (MRI) approach in 2- to 5-years of age. Both inspection times and VFM were found to increase with age. Greater VFM in the right and left occipital lobes, the body of the corpus callosum, and the right cerebellum was significantly associated with shorter inspection times, after controlling for age. A hierarchical regression showed that VFM in the left occipital lobe predicted inspection times over and beyond the effects of age and the VFM in the other brain regions. These findings are consistent with the hypothesis that myelin supports processing speed in early childhood

Predefined brain regions, for which VF_M was measured using the mcDESPOT [multicomponent Driven Equilibrium Single Pulse Observation of T₁ and T₂], white matter imaging technique.

<p>Predefined brain regions, for which VF_M was measured using the mcDESPOT [multicomponent Driven Equilibrium Single Pulse Observation of T₁ and T₂], white matter imaging technique.</p

Descriptive statistics for age, inspection times and myelin volume fraction (VF_M), raw Pearson correlations with age or inspection times, and partial correlations with inspection times (controlling for age).

<p>VF_M = myelin volume fraction. M = Mean. SD = Standard Deviation. L. = Left. R. = Right. SLF = Superior longitudinal fasciculus. CC = Corpus callosum. Significant correlations appear in bold.</p><p>Descriptive statistics for age, inspection times and myelin volume fraction (VF_M), raw Pearson correlations with age or inspection times, and partial correlations with inspection times (controlling for age).</p

Significant Pearson correlations between inspection times [ln ms] and myelin volume fraction (VF_M) in the left occipital lobe, left and right internal capsules, and right superior longitudinal fasciculus (SLF), before controlling for age.

<p>Significant Pearson correlations between inspection times [ln ms] and myelin volume fraction (VF_M) in the left occipital lobe, left and right internal capsules, and right superior longitudinal fasciculus (SLF), before controlling for age.</p

Significant Pearson correlations of age [in months] with inspection times [ln ms] and myelin volume fraction (VF_M) in the genu of the corpus callosum.

<p>Significant Pearson correlations of age [in months] with inspection times [ln ms] and myelin volume fraction (VF_M) in the genu of the corpus callosum.</p