Wavelet coherence analysis of prefrontal oxygenation signals in elderly subjects with hypertension

Zengyong Li, Ming Zhang, Ruofei Cui, Qing Xin, Lu Liqian, Weiei Zhou, Qingyu Han, Yuanjin Gao

Research output: Journal article publicationJournal articleAcademic researchpeer-review

20 Citations (Scopus)


This study aims to assess the prefrontal functional connectivity in elderly subjects with hypertension during the resting state using wavelet coherence analysis of changes in prefrontal tissue oxyhaemoglobin concentrations (Δ[HbO2]) signals measured by near-infrared spectroscopy (NIRS). Continuous recordings of NIRS signals were obtained from the left and right prefrontal lobes in 24 elderly subjects with hypertension (age: 70.7 ± 8.4 years) and 26 elderly normotensive subjects (age: 70.6 ± 7.9 years) during the resting state. The coherence between the left and right prefrontal oscillations in four frequency intervals (I, 0.4 Hz to 2 Hz; II, 0.15 Hz to 0.4 Hz; III, 0.05 Hz to 0.15 Hz; and IV, 0.02 Hz to 0.05 Hz) was analyzed using wavelet coherence method. The Δ[HbO2] oscillations showed significant wavelet coherence (WCO) in intervals I and III, and significant wavelet phase coherence (WPCO) in intervals from I to IV. Remarkably, in elderly subjects with hypertension, the WCO and WPCO in interval III were significantly lower in the left and right prefrontal regions than in healthy elderly subjects (p = 0.014 for WCO, p = 0.007 for WPCO). The lower coherence in interval III indicates a decreased synchronization of neural control in the left and right prefrontal regions in elderly subjects with hypertension. This might suggest a weakened brain functional connectivity in the elderly subjects with hypertension.
Original languageEnglish
Pages (from-to)777-791
Number of pages15
JournalPhysiological Measurement
Issue number5
Publication statusPublished - 1 May 2014


  • cerebral oxygenation
  • functional connectivity
  • hypertension
  • near-infrared spectroscopy
  • phase coherence
  • spontaneous oscillations
  • wavelet coherence

ASJC Scopus subject areas

  • Biophysics
  • Physiology
  • Physiology (medical)

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