Table 1.

Overview of the statistically significant EEG and NIRS results.

		AEP				TFA	NIRS
		Mean amplitude		Peak amplitude		Desynchronization (4–8 Hz)	Activation (oxy and/or deoxy)
		N1	P2	N1	P2
6 mo	Fast	+	=	+	−	−	LH > RH (3)
							RH > LH (6)
	Slow	−	=	−	+	+	RH > LH (1, 6)
3 mo	Fast	+	=	+	−	−	LH > RH (2, 3, 5)
	Slow	−	=	−	+	−	LH > RH (2, 5)

Displays the comparison of fast and slow acoustic modulations for the two age groups separately. 6 mo, 6 month old infants; 3 mo, 3 month old infants; AEP, auditory-evoked potential, TFA, time-frequency analysis; NIRS, near-infrared spectroscopy; N1, first negativity; P2, second positivity; LH, left hemisphere; RH, right hemisphere; (+), increase; (−), decrease; (=), no difference. Location of the areas measured by means of NIRS are described by the number in brackets (please also refer to Figure 1): (1) inferior frontal, (2) superior frontal, (3) inferior temporal, (4) superior temporal, (5) posterior temporal, and (6) temporo-parietal.