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MRI scan quantity and quality in childhood
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Conclusion
We report that participants’ scanner related distress was associated to scan quantity, but not to scan quality. Overall, scan quantity was high, as 88% of the children that started the protocol also completed it. The percentage of sufficient scans was considerably higher (49%) in the first 30 minutes of the protocol than in the full 60-minute protocol (20%), indicating that shorter scan protocols have less attrition. Consistent with previous studies (Couvy-Duchesne et al., 2014; Engelhardt et al., 2017), the behavioral genetic analyses revealed heritability effects on head motion, with heritability estimates ranging from 29-65%. Importantly, however, our results also show that after exclusion based on excessive head motion, heritability estimates declined to 0-14%, indicating that MRI findings of motion corrected and quality-controlled data are not substantially confounded by genetic factors. Moreover, shared environmental influences played a larger role (15-33%) in the variation in quality controlled head motion, suggesting that head motion can be influenced by participant instruction and scanner adjustments. These results provide insight in the genetic and environmental influences on scan quantity and quality and can inform future studies on developmental neuroimaging.
Acknowledgements
We thank Prof. dr. Eveline Crone, Dr. Anna van Duijvenvoorde, Prof. dr. Marian Bakermans-Kranenburg, and Prof. dr. Marinus van IJzendoorn for providing constructive comments on previous versions of the manuscript and for their helpful discussions on the behavioral genetic modeling. The Leiden Consortium on Individual Development is funded through the Gravitation program of the Dutch Ministry of Education, Culture, and Science and the Netherlands Organization for Scientific Research (NWO grant number 024.001.003).
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