Multimodal recording of brain activity in term newborns during photic stimulation by near-infrared spectroscopy and electroencephalography

Abstract

In this study 14 healthy term newborns (postnatal mean age 2.1 days) underwent photic stimulation during sleep on two different days. Near-infrared spectroscopy (NIRS) and electroencephalography (EEG) was acquired simultaneously. The aims of the study were: to determine (i) the sensitivity and (ii) the repeatability of NIRS to detect the hemodynamic response, (iii) the sensitivity and (iv) the repeatability of EEG to detect a visual evoked potential (VEP), (v) to analyze optical data for the optical neuronal signal, and (vi) to test whether inadequate stimulation could be reason for absent hemodynamic responses. The results of the study were as follows. (i) Sensitivity of NIRS was 61.5% to detect hemodynamic responses; (ii) their reproducibility was 41.7%. A VEP was detected (iii) in 96.3% of all subjects with (iv) a reproducibility of 92.3%. (v) In two measurements data met the criteria for an optical neuronal signal. The noise level was 9.6·10-5% change in optical density. (vi) Insufficient stimulation was excluded as reason for absent hemodynamic responses. We conclude that NIRS is an promising tool to study cognitive activation and development of the brain. For clinical application, however, the sensitivity and reproducibility on an individual level needs to be improved. Abstract. In this study 14 healthy term newborns (postnatal mean age 2.1 days) underwent photic stimulation during sleep on two different days. Near-infrared spectroscopy (NIRS) and electroencephalography (EEG) was acquired simultaneously. The aims of the study were: to determine (i) the sensitivity and (ii) the repeatability of NIRS to detect the hemodynamic response, (iii) the sensitivity and (iv) the repeatability of EEG to detect a visual evoked potential (VEP), (v) to analyze optical data for the optical neuronal signal, and (vi) to test whether inadequate stimulation could be reason for absent hemodynamic responses. The results of the study were as follows. (i) Sensitivity of NIRS was 61.5% to detect hemodynamic responses; (ii) their reproducibility was 41.7%. A VEP was detected (iii) in 96.3% of all subjects with (iv) a reproducibility of 92.3%. (v) In two measurements data met the criteria for an optical neuronal signal. The noise level was 9.6 · 10 −5 % change in optical density. (vi) Insufficient stimulation was excluded as reason for absent hemodynamic responses. We conclude that NIRS is an promising tool to study cognitive activation and development of the brain. For clinical application, however, the sensitivity and reproducibility on an individual level needs to be improved.

Investigation of the Pattern of the Hemodynamic Response as Measured by Functional Near-Infrared Spectroscopy (fNIRS) Studies in Newborns, Less Than a Month Old: A Systematic Review

“…The remaining six studies employed a stroboscopic light to elicit a visual response. The studies show similar results for Δ[HbO 2 ], with most studies observing a positive change in this parameter apart from Kusaka et al ( 2005 ) who observed a negative Δ[HbO 2 ] and Biallas et al ( 2012 ) who observed both positive and negative Δ[HbO 2 ]. Kusaka et al ( 2005 ) additionally observed an increase in Δ[HHb].…”

“…Nine fNIRS studies used visual stimulation. Visual stimuli generally used either a checkerboard pattern (Meek et al, 1998 ; Liao et al, 2010 , 2012 ) or a stroboscopic light (Hoshi et al, 2000 ; Taga et al, 2003 ; Kusaka et al, 2005 ; Karen et al, 2008 ; Biallas et al, 2012 ; Shibata et al, 2012 ). All studies monitored the occipital lobe, with some studies additionally monitoring the frontal lobe (Taga et al, 2003 ) and temporal and parietal lobe (Shibata et al, 2012 ).…”

“…Kusaka et al ( 2005 ) additionally observed an increase in Δ[HHb]. Two studies did not report the Δ[HHb] results (Biallas et al, 2012 ; Shibata et al, 2012 ), two studies reported a varied response (both positive and negative; Hoshi et al, 2000 ; Taga et al, 2003 ) and one study reported a negative Δ[HHb] (Karen et al, 2008 ). Hoshi et al ( 2000 ) also noted a relatively slow recovery of the fNIRS parameters after the end of the stimulus compared to rapid recoveries previously reported in adults.…”

Cerebral hemodynamic responses in preterm-born neonates to visual stimulation: classification according to subgroups and analysis of frontotemporal–occipital functional connectivity

“…In previous fNIRS studies by our group, we demonstrated the ability to measure evoked hemodynamic changes in the occipital cortex after visual stimulation in term-born neonates within their first days of life. [18][19][20] However, the development of the HRF pattern in the human brain remained unclear; some fNIRS studies reported an inverted HRF pattern (i.e., a decrease in blood flow or [O 2 Hb]) in young infants in response to perceptual stimuli, whereas some studies did not. 2,21,22 This has been a controversial issue, and investigations about this aspect in preterm-born neonates are particularly sparse, partly because the investigation of HRFs of these neonates using fNIRS is a relatively new subject.…”

Simultaneous functional near-infrared spectroscopy and electroencephalography for monitoring of human brain activity and oxygenation: a review

“…This result highlights the need for integrated brain monitoring in newborns. As for sensory stimuli, a combined approach can also be successfully applied to investigate the newborn cerebral responses to stimuli obtained with other modalities, for example, visual responses during photic stimulation, 121 as well as to monitor the brain ability of sensory processing during normal development, such as acoustic processing in infants within the first 6 months of life 122 …”