Hand coordination skills similar between teens born very preterm, at term

Hand coordination-related brain activation is affected by very preterm birth, with majority of the effects found for the nondominant hand, a recent study has found. Clinical performance during the hand coordination tasks is comparable between adolescents born very preterm and those born at term.

The study included 34 right-handed adolescents born <32 weeks or with birthweight ≤1,500 g. At 13 years of age, finger opposition and diadochokinesis were assessed, while brain functional magnetic resonance imaging (fMRI) was conducted to visualize brain activation. A parallel group of 37 term controls was also included.

At the time of fMRI, the median age in the very-preterm and control groups were 12.6 and 12.9 years, respectively. Background characteristics were comparable between groups.

Hand coordination did not significantly differ between the two groups. For instance, normal finger opposition performance in the right hand was similar between groups in terms of smoothness (p=1.0), transition (p=0.5) and associated movements (p=1.0). The same was true in the left hand, as well as in terms of diadochokinesis in both hands.

In contrast, hand coordination-related brain activation was significantly altered in the very-preterm vs control group, particularly in the left-handed tasks, who showed significantly stronger activation in the right precentral (p=0.01) and postcentral (p=0.03) gyrus during diadochokinesis. Right-handed tasks induced no such differences in activation.

Moreover, location of activation was likewise similar between groups when performing tasks for the same hand. The contralateral primary sensorimotor cortex, bilateral medial and lateral premotor areas, and the occipital cortex were among the most activated regions.

“This study demonstrates that hand coordination skills were equal in adolescents born very preterm and at term,” the researchers said. “This finding may reflect a compensatory neural mechanism that enables appropriate hand coordination performance compared with those born at term.”