Fractal and Noisy CBV Dynamics in Humans: Influence of Age and Gender

@article{Eke2006FractalAN,
  title={Fractal and Noisy CBV Dynamics in Humans: Influence of Age and Gender},
  author={Andras Eke and Peter Herman and M{\'a}rton Albert Hajnal},
  journal={Journal of Cerebral Blood Flow \& Metabolism},
  year={2006},
  volume={26},
  pages={891 - 898}
}
The complexity of spontaneous cerebral blood volume (CBV) fluctuations can emerge from random, fractal, or chaotic processes. Our aims were to define the contribution of these patterns to the observed complexity and to evaluate the effect of age and gender on it. The total hemoglobin content as the measure of CBV was monitored by near-infrared spectroscopy on volunteers (men n = 19, age = 20 to 78 years; women n = 23, age = 21 to 79 years). Random and fractal patterns were distinguished by the… 
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References

SHOWING 1-10 OF 46 REFERENCES
Fractal characterization of complexity in temporal physiological signals.
TLDR
The authors demonstrate the importance of incorporating a step of signal classification according to the fGn/fBm model prior to fractal analysis by showing that missing out on signal class can result in completely meaningless fractal estimates.
Mechanisms underlying chaotic vasomotion in isolated resistance arteries: roles of calcium and EDRF.
TLDR
It is concluded that the nonlinear interaction between a fast membrane oscillator and a slow intracellular oscillator generates chaos in vascular smooth muscle and that exogenous constrictor agonists and EDRF may be regarded as permissive and modulatory influences, respectively.
Physiological time series: distinguishing fractal noises from motions
TLDR
A new method using signal summation conversion (SSC) greatly improves the classification and the reliability of Ĥ, the estimates of H, for the times series, and suggests that the flow signal is the summation of a set of local velocities from neighboring vessels that are negatively correlated, as if induced by local resistance fluctuations.
Fractal analysis of spontaneous fluctuations in human cerebral hemoglobin content and its oxygenation level recorded by NIRS.
TLDR
This study has applied the fractal model as implemented in a combination of the power spectral density (PSD) and the scaled windowed variance (SWV) methods in the analysis of human cerebrocortical hemoglobin signals in an attempt to assess their temporal pattern.
Measuring the Strangeness of Strange Attractors
Spontaneous Low-Frequency Oscillations Decline in the Aging Brain
TLDR
Spontaneous low-frequency oscillations of oxyhemoglobin and deoxyhemoglobin declined strongly with aging during both rest and visual stimulation, which might indicate a declining spontaneous activity in microvascular smooth muscle cells, in conjunction with an increased vessel stiffness with aging.
Chaos and physiology: deterministic chaos in excitable cell assemblies.
TLDR
This review examined the emerging science of deterministic chaos (nonlinear systems theory) and its application to selected physiological systems and to the neurosciences, demonstrating that the dynamics of neural mass activity reflect psychopathological states.
Determining Lyapunov exponents from a time series
Oscillations in cerebral haemodynamics. Implications for functional activation studies.
TLDR
The blood oxygenation level dependent (BOLD) contrast signal in functional magnetic resonance imaging (fMRI) provides highly spatially resolved deoxygenation maps of the activated cortex and several studies have been designed to elucidate its origin.
On the accuracy of spectrum analysis of red noise processes using maximum entropy and periodogram methods: Simulation studies and application to geophysical data
Power spectra, estimated by the maximum entropy method and by a fast Fourier transform based periodogram method, are compared using simulated time series. The times series are computer generated by…
...
...