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Bilateral Motor Responses to Transcranial Magnetic Stimulation in Preterm Children at 9 Years of Age
A Marita Valkama1,2,3, Seppo O Rytky4, Päivi M Olsén1,2
1Department of Children and Adolescents, Oulu University Hospital, Oulu, Finland.
Insights
Preterm-born children at 9 years old show variations in motor pathways, with some exhibiting mild clumsiness. Transcranial magnetic stimulation (TMS) reveals differences in motor-evoked potentials (MEPs) compared to term-born peers.
Area of Science:
- Neuroscience
- Developmental Pediatrics
- Motor Control
Background:
- Preterm birth can impact neurodevelopmental outcomes.
- Assessing corticospinal tract integrity is crucial for understanding motor development in children.
Purpose of the Study:
- To evaluate the integrity of motor tracts in nondisabled preterm-born (PT) children at 9 years of age.
- To compare motor pathway responses between PT and term-born (T) children using transcranial magnetic stimulation (TMS).
Main Methods:
- 18 PT and 13 T children without motor disabilities underwent TMS.
- Motor-evoked potentials (MEPs) were measured from abductor pollicis brevis (APB) and tibialis anterior (TA) muscles.
- Bilateral muscle responses were assessed.
Main Results:
- 83.3% of PT children and 23.1% of T children displayed mild clumsiness (p=0.001).
- Delayed ipsilateral responses were observed in PT children for upper extremities.
- Ipsilateral responses were more frequent in upper than lower extremities.
Conclusions:
- Bilateral motor responses and ipsilateral conduction are observed in both PT and T children at 9 years.
- These findings highlight developmental and neurophysiological variability.
- MEPs are a viable measure for assessing corticospinal tract integrity in PT children.
Objective:
This study was aimed to evaluate motor tracts integrity in nondisabled preterm-born (PT) children at 9 years of age.
Methods:
Overall, 18 PT and 13 term-born (T) children without motor disability were assessed by transcranial magnetic stimulation (TMS). Motor-evoked potentials (MEPs) were measured bilaterally from the abductor pollicis brevis (APB) and the tibialis anterior (TA) muscles. Muscle responses could be stimulated from all patients.
Results:
Overall, 83.3 and 23.1% of PT and T children, respectively, had mild clumsiness (p = 0.001). One PT and three T children had immediate bilateral responses in the upper extremities. Seven PT children had delayed ipsilateral APB responses after left and ten after right TMS. Three controls had delayed ipsilateral responses. Ipsilateral lower extremity responses were seen in one PT after right and two PT children and one T child after left TMS. The results did not correlate to groups, genders, clumsiness, or handedness.
Conclusion:
Children of PT and T may have bilateral motor responses after TMS at 9 years of age. Ipsilateral conduction emerges immediately or more often slightly delayed and more frequently in upper than in lower extremities.
Significance:
Bilateral motor conduction reflects developmental and neurophysiological variability in children at 9 years of age. MEPs can be used as a measure of corticospinal tract integrity in PT children.
