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Resting fluctuations in arterial carbon dioxide induce significant low frequency variations in BOLD signal
We have identified a significant source of low-frequency variation in blood oxygen level-dependent (BOLD) magnetic resonance imaging (MRI) signal arising from spontaneous fluctuations in arterial carbon dioxide level in volunteers at rest. Expand
Relationship between middle cerebral artery blood velocity and end-tidal PCO2 in the hypocapnic-hypercapnic range in humans.
This study examined the relationship between cerebral blood flow (CBF) and end-tidal PCO2 (PETCO2) in humans. We used transcranial Doppler ultrasound to determine middle cerebral artery peak bloodExpand
Dynamics of the cerebral blood flow response to step changes in end-tidal PCO2 and PO2 in humans.
This study examined the dynamics of the cerebral blood flow response to hypoxia and hypercapnia in humans. Middle cerebral artery blood flow (MCAF) was assessed continuously using transcranialExpand
Effects of cardiorespiratory fitness and cerebral blood flow on cognitive outcomes in older women
The mechanisms by which aerobic fitness confers beneficial effects on cognition with aging are unclear but may involve cerebrovascular adaptations. In a cross-sectional study of women from theExpand
Cerebrovascular responses to altitude
The regulation of cerebral blood flow (CBF) is a complex process that is altered significantly with altitude exposure. Acute exposure produces a marked increase in CBF, in proportion to the severityExpand
Intermittent Hypoxia Increases Arterial Blood Pressure in Humans Through a Renin-Angiotensin System–Dependent Mechanism
Intermittent hypoxia (IH) is believed to contribute to the pathogenesis of hypertension in obstructive sleep apnea through mechanisms that include activation of the renin-angiotensin system. TheExpand
Differential responses to CO2 and sympathetic stimulation in the cerebral and femoral circulations in humans
The relative importance of CO2 and sympathetic stimulation in the regulation of cerebral and peripheral vasculatures has not been previously studied in humans. We investigated the effect ofExpand
Nonlinear modeling of the dynamic effects of arterial pressure and CO2 variations on cerebral blood flow in healthy humans
We show that cerebral autoregulation is strongly nonlinear and dynamic (frequency-dependent). Expand
Cardiovascular and cerebrovascular responses to acute hypoxia following exposure to intermittent hypoxia in healthy humans
Intermittent hypoxia (IH) is thought to be responsible for many of the long‐term cardiovascular consequences associated with obstructive sleep apnoea (OSA). Experimental human models of IH can aid inExpand
Cerebrovascular Reserve: The Link Between Fitness and Cognitive Function?
Better physical fitness in later life is associated positively with cognitive functioning. Novel data suggest that this association is mediated, in part, by increases in brain perfusion and theExpand