Bilateral hemodynamic responses to auditory stimulation in newborn infants

Abstract

We studied hemodynamic auditory evoked responses of 20 healthy full-term neonates with near-infrared spectroscopy. The instrument used allows the measurements to be performed simultaneously above both auditory cortices. The stimulation consisted of 5-s trains of sound (700-ms interstimulus interval) with a 25-s silent interval. In response to the stimulation, a significant increase in concentration of oxygenated hemoglobin was detected in 14 out of 21 measurements. The mean latency of the largest response was 9.63+/-2.20 s (mean+/-SD) and the mean amplitude was 1.02+/-0.53 microM. The response amplitude was significantly larger in active (1.28+/-0.59 microM) than in quiet sleep (0.76+/-0.32 microM). The latency of the oxygenated hemoglobin concentration response was significantly shorter (r=-0.70 and p=0.0023) for infants with higher gestational age.

Optical imaging of infants' neurocognitive development: Recent advances and perspectives

“…However, they provide less equivalent temporal information unless multiple frequencies are employed, and operate less efficiently at very low intensities (Nissilä et al, 2006). Optical topography systems have been built based on both time-domain (Quaresima et al, 2005) and frequency-domain (Danen et al, 1998;Choi et al, 2004;Kotilahti et al, 2005) technologies. Their disadvantage compared to CW systems is their comparatively high cost, and slower sampling rates (particularly for photon-counting systems).…”

Simultaneous measurement of neuronal activity and cortical hemodynamics by unshielded magnetoencephalography and near-infrared spectroscopy

“…14 NIRS studies with auditory cortex activation have been also reported for both adults [27][28][29] and infants. 30,31 These studies are mainly based on linguistic viewpoint. On the other hand, this study focuses on simple auditory stimuli.…”

Spatiotemporal properties of cortical haemodynamic response to auditory stimuli in sleeping infants revealed by multi-channel near-infrared spectroscopy

“…In contrast, NIRS has the great advantage of enabling investigation of stimulusinduced cortical activation in relation to perceptual and cognitive activity in awake infants [13,25,[53][54][55][56][57][58][59]60,61]. Regarding the development of auditory and language perception, NIRS measurements have been performed during sleep [14,[62][63][64][65][66][67]. Most of these studies have examined whether the cortical regions of interest in infants of different ages selected using behavioural studies showed hypothesized responses based on adult neuroimaging studies.…”