Imaging Cerebral Energy Metabolism in Healthy Infants

Area of Science:

• Neuroscience
• Developmental Biology
• Biomedical Engineering

Background:

• Infant brain function and specialization are largely unexplored.
• Non-invasive methods are needed to study brain activity in infants.
• Broadband near-infrared spectroscopy (bNIRS) offers potential for measuring cerebral haemodynamics and cellular oxygen utilization.

Purpose of the Study:

• To explore infant brain function and specialization using bNIRS.
• To measure haemodynamic changes and cytochrome-c-oxidase (oxCCO) oxidation state in infants.
• To generate the first reconstructed images of metabolic changes in healthy, awake infants.

Main Methods:

• Used bNIRS to measure changes in oxygenated haemoglobin (Δ[HbO2]), deoxygenated haemoglobin (Δ[HHb]), and oxCCO oxidation state (Δ[oxCCO]) in 4-to-7-month-old infants.
• Applied the UCLn algorithm to calculate concentration changes from light attenuation data across 120 wavelengths (780-900 nm).
• Utilized a multispectral approach for volumetric image reconstruction and mapped these onto an infant cortical surface model.

Main Results:

• Spatially localized activation of Δ[oxCCO] and Δ[HbO2] was observed over the temporo-parietal region in response to social stimuli.
• Reconstructed images visualized metabolic changes in response to both social and non-social stimuli.
• Demonstrated the feasibility of generating metabolic images in awake infants.

Conclusions:

• bNIRS can non-invasively measure cerebral haemodynamics and cellular oxygen utilization in infants.
• Social stimuli elicit specific, localized brain activation patterns in the infant temporo-parietal cortex.
• This study presents the first reconstructed metabolic images of the infant brain, opening new avenues for developmental neuroscience research.