Characteristics of electroencephalogram power and event-related potential in neonatal auditory cognitive development

Objective To investigate the characteristics of cognitive development in different aged neonates. Methods Sixty-two newborns were randomly selected from relatively normal full-term babies in Changzhou Children's Hospital from December 2013 to September 2015. Electroencephalogram (EEG) and event-related potentials (ERP) were recorded with the auditory Oddball paradigm. Cognitive EEG delta power and the N2 wave area of different ages (1-10, 11-20 and 21-28 days) were compared. Paired t test, analysis of variance and the LSD test were used for statistical analysis. Results (1) Delta power in the resting and cognition state: neonatal cognitive delta power in the 11-20 and 21-28 days old groups was (268.22±132.09) and (236.01±97.40) μV2, respectively, significantly higher than the resting delta power of the same groups [(175.80±80.80) and (178.78±104.74) μV2, t=2.539 and 2.845, P=0.020 and 0.010, respectively]. (2) Cognitive delta power in different aged neonates: cognitive delta power in the 11-20 and 21-28 days old groups was (268.22±132.09) and (236.01±97.40) μV2, respectively, higher than that of the 1-10 days old group [(116.70±56.70) μV2], with statistically significant difference (LSD test, both P<0.05). (3) Neonatal ERP: ERP of the 1-10 days old group presented with multiple peaks of a flat composite wave, in the 11-20 and 21-28 days old groups, the N2 wave showed a regular and rising trend, gradually to a single wave, and became gradually mature. The N2 wave area in the 11-20 and 21-28 days old groups was (6 435.08±2 212.34) and (6 536.75±1 969.86) ms·μV, respectively, which was larger than that in the 1-10 days old group [(4 230.04±1 550.55) ms·μV](LSD test, both P<0.05). Conclusions Neonatal cognitive development is enhanced with age and there may be a period of more rapid cognitive development, especially at 11-20 days of age. Key words: Acoustic stimulation; Cognition; Electroencephalography; Evoked potentials; Infant, newborn