Neuromagnetic biomarkers of visuocortical development in healthy children

Department of Neurology, Cincinnati Children's Hospital Medical Center, Cincinnati, OH 45220, USA.
Clinical neurophysiology: official journal of the International Federation of Clinical Neurophysiology (Impact Factor: 3.1). 09/2010; 121(9):1555-62. DOI: 10.1016/j.clinph.2010.03.029
Source: PubMed


The objective of the present study was to investigate noninvasive biomarkers for visuocortical development in healthy children.
Sixty healthy children and 20 adults were studied with a whole-head magnetoencephalography (MEG) system. The adults were included to find out when the markers stabilize. Visual evoked magnetic fields (VEFs) were evoked with full-field pattern-reversal checks.
Three response peaks were identified at 77+/-8 ms (M75), 111+/-9 ms (M100) and 150+/-11 ms (M145) for children. The latency of M75 and M100 decreased with age (p<0.01). The amplitude ratio of M100/M75 increased significantly with age (p<0.001). The differences of MEG source images between the left and right occipital cortices for M75 and M145 increased significantly with age (r=0.47 and 0.46, respectively, p<0.01).
The latency of M75 and M100 and the amplitude ratio of M100/M75 are robust biomarkers for the development of visual function in children.
The development of visual function in childhood is noninvasively measurable. The results lay a foundation for quantitative identification of developmental delay and/or abnormalities of visual function in children with brain disorders.

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    • "Of note, the study of high-frequency brain signals may shed light on some of the fundamental mechanisms of neuronal functions and brain disorders. Numerous challenges exist in the study of high-frequency brain signals with magnetoencephalography (MEG) and electroencephalography (EEG) (Xiang et al., 2004, 2010, 2013; Dalal et al., 2008; Papadelis et al., 2009; Chen et al., 2010; Gotman, 2010; Gummadavelli et al., 2013). First, the size of high sampling rate data can be over 12 terabytes (TB) (Blanco et al., 2011). "
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