An exploratory study of EEG connectivity during the first year of life in preterm and full-term infants

Aim to evaluate EEG connectivity during the first year of age in healthy full-term infants and preterm infants with prenatal and perinatal risk factors for perinatal brain damage. Methods Three groups of infants were studied: healthy at full-term infants (n = 71), moderate and late preterm infants (n = 54), and very preterm infants (n = 56). All preterm infants had perinatal or/and perinatal risk factors for brain damage. EEG was obtained during phase II of natural NREM sleep. EEG analysis was performed in 24 segments of 2.56 s free of artifacts. For the calculation of EEG sources, the spectral Structured Sparse Bayesian Learning (sSSBL) was used. Connectivity was computed by the phase-lag index. Results In healthy full-term infants, EEG interhemispheric connectivity in the different frequency bands followed similar trends with age to those reported in each frequency band: delta connectivity decreases, theta increases at the end of the year, in the alpha band, different trends were observed according to the region studied, and beta interhemispheric connectivity decreases with age. EEG connectivity in preterm infants showed differences from the results of the term group. Discussion Important structural findings may explain the differences observed in EEG connectivity between the term and preterm groups. Conclusion The study of EEG connectivity during the first year of age gives essential information on normal and abnormal brain development.