Spontaneous low-frequency oscillations decline in the aging brain

J Cereb Blood Flow Metab. 2004 Oct;24(10):1183-91. doi: 10.1097/01.WCB.0000135231.90164.40.

Abstract

It is well known that aging leads to a degeneration of the vascular system. Hence, one may hypothesize that spontaneous oscillations decrease in the cerebral microvasculature with aging. Accordingly, the authors investigated the age dependency of spontaneous oscillations in the visual cortex during rest and functional activation. Functional near-infrared spectroscopy was used because it is particularly sensitive to the microvasculature. Visual stimulation led to an increase of oxyhemoglobin, total hemoglobin, and a decrease of deoxyhemoglobin, without any influence of age. Peaks of normalized power spectral density were detected for spontaneous low-frequency (0.07 to 0.11 Hz) and very-low-frequency (0.01 to 0.05 Hz) oscillations, with a higher amplitude for oxyhemoglobin than for deoxyhemoglobin. Spontaneous low-frequency oscillations of oxyhemoglobin and deoxyhemoglobin declined strongly with aging during both rest and visual stimulation. Reduction of spontaneous low-frequency oscillations might indicate a declining spontaneous activity in microvascular smooth muscle cells, in conjunction with an increased vessel stiffness with aging.

Publication types

  • Comparative Study

MeSH terms

  • Adult
  • Aged
  • Aging / physiology*
  • Biological Clocks / physiology
  • Cerebrovascular Circulation / physiology*
  • Female
  • Hemoglobins / metabolism
  • Humans
  • Male
  • Microcirculation / physiology
  • Middle Aged
  • Oxyhemoglobins / metabolism
  • Spectroscopy, Near-Infrared
  • Visual Cortex / blood supply*

Substances

  • Hemoglobins
  • Oxyhemoglobins
  • deoxyhemoglobin