Quantitative Analysis of Intracranial Volume Slow-Wave Fluctuations

This paper describes the results from the application of spectral analysis to the interpretation of slow volume fluctuations inside the intracrania-spinal cavities, recorded during 3 minute data collection periods by a rheoencephalography (REG) method, using a bio-impedance current frequency of 100 kHz and a medial fronto-mastoidal electrode sending position. The collected data was processed with Chart 5 software to obtain the spectra for each recording. Participants were from three age groups 20-30, 30-45 and older than 45 years. 20-30 subjects from each group were investigated, as well as a number of subject patients with neurological pathology, treated with an osteopathic manual technique. 5-7 spectral peaks were revealed in the 0 – 0.3 Hz frequency range. Hemispheric asymmetry was observed in every age group after mean averaging analysis. In the cases of neural pathology the osteopathic treatment intervention changed the amplitude and frequency of the spectral peaks. This study's results suggest that the application of spectral analysis to slow volume fluctuations may provide information in evaluating the integrative relationships of the cerebrovascular system, cerebrospinal fluid (CSF) mobility and cranial pulse compliance. This has implications for non-invasive measurement of the rate of brain function in neurologically normal and non-normal neurological states in humans.