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[Cerebral blood flow. Changes in regulation with aging].

In subjects without cardiovascular or neuronal diseases ageing does not seem to be accompanied by a significant fall in global cerebral blood flow at rest. Yet non-negligible changes in cerebral blood flow rate can be demonstrated by haemodynamic or metabolic stimuli. Several intra- and extracranial vascular mechanisms may be involved in these changes. During ageing, a decrease of carotid artery compliance due to parietal calcium deposition might be an important factor in the disturbance of cerebral blood flow regulatory mechanisms.