Rethinking neurovascular coupling in white matter

Area of Science:

• Neuroscience
• Physiology
• Biochemistry

Background:

• Neurovascular coupling (NVC) describes the link between neural activity and blood flow, primarily studied in gray matter.
• Gray matter exhibits activity-dependent functional hyperemia, increasing blood supply with neural demand.
• White matter's vascular-metabolic principles remain less understood compared to gray matter.

Purpose of the Study:

• To propose a novel mechanism for neurovascular coupling (NVC) in white matter.
• To investigate the distinct vascular-metabolic principles governing white matter function.
• To elucidate how white matter maintains energy homeostasis.

Main Methods:

• Theoretical modeling of white matter vascular-metabolic coupling.
• Analysis of existing literature on white matter physiology.
• Comparative study of energy homeostasis mechanisms in gray and white matter.

Main Results:

• White matter NVC may operate via a reserve-based system.
• Local energetic reserves are crucial for sustaining white matter energy homeostasis.
• This mechanism allows white matter to tolerate transient mismatches between metabolic demand and vascular supply.

Conclusions:

• White matter employs a unique, reserve-based form of neurovascular coupling.
• This distinct mechanism supports energy homeostasis in white matter.
• Understanding white matter NVC is crucial for comprehending brain energetics.