Neurovascular coupling in the developing neonatal brain at rest

Abstract

The neonatal brain is an extremely dynamic organization undergoing essential development in terms of connectivity and function. Several functional imaging investigations of the developing brain have found neurovascular coupling (NVC) patterns that contrast with those observed in adults. These discrepancies are partly due to that NVC is still developing in the neonatal brain. To characterize the vascular response to spontaneous neuronal activations, a multiscale multimodal noninvasive approach combining simultaneous electrical, hemodynamic, and metabolic recordings has been developed for preterm infants. Our results demonstrate that the immature vascular network does not adopt a unique strategy to respond to spontaneous cortical activations. NVC takes on different forms in the same preterm infant during the same recording session in response to very similar types of neural activation. This includes (a) positive stereotyped hemodynamic responses (increases in HbO, decreases in HbR together with increases in rCBF and rCMRO2), (b) negative hemodynamic responses (increases in HbR, decreases in HbO together with decreases in rCBF and rCMRO2), and (c) Increases and decreases in both HbO-HbR and rCMRO2 together with no changes in rCBF. Age-related NVC maturation is demonstrated in preterm infants,which can contribute to a better understanding/prevention of cerebral hemodynamic risks in these infants. K E Y W O R D Sdiffuse correlation spectroscopy, electroencephalography, near-infrared spectroscopy, premature neurovascular coupling, resting state

Wavelet-based neurovascular coupling can predict brain abnormalities in neonatal encephalopathy

“…Development in early infancy suggests that the neonatal brain may undergo complex variations in hemodynamics that differ from the adult brain ( Nourhashemi et al, 2020 , Roche-Labarbe et al, 2007 ). The hyperemic response to neuronal activation, for example, can occur within seconds, appears to be mediated by astrocytes and to be highly localized ( Ariel et al, 2004 ).…”

The duration of intrauterine development influences discrimination of speech prosody in infants

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Assessing cerebral blood flow, oxygenation and cytochrome c oxidase stability in preterm infants during the first 3 days after birth

“…Wavelet coherence, which has been used in a number of neonatal brain monitoring studies 23 , 58 – 60 , was used to assess the temporal correlation between the three dynamic signals across the frequency range 0.001 to 0.005 Hz: rCBF and StO 2 , rCBF and ΔoxCCO, and StO 2 and ΔoxCCO. Coherence ranges from 0 to 1 and reflects the cross-correlation between two time series as a function of frequency, with a value of 0 indicating no correlation and 1 indicating complete agreement.…”