Clinical Neuroscience

[Analysis of the EEG changes caused by subcortical stroke based on chaos theory ]

MOLNÁR Márk1, GÁCS Gyula2, ÚJVÁRI Gábor1, SKINNER E. James3, KARMOS György1

MAY 20, 1997

Clinical Neuroscience - 1997;50(05-06)

[The conventional electrophysiological methods used to analyse the functional characteristics of the nervous system are not able to grasp its non-linear and random features. Of the methods based on chaos theory, correlation dimension analysis can be used to quantify the complexity of the analysed signal, such as the elektroencefalogram. The new version of this method - developed by the authors -, the point correlation dimension is more accurate than other currently used algorithms. The purpose of the present paper is to compare the sensitivity of the conventional electrophysiological methods with those developed on the basis of chaos theory in a case where a small subcortical stroke was present. By mapping the scalp distribution of the point correlation dimension of the electroencephalogram, recorded when the patient had no neurological symptoms, a significantly low dimensional area - as compared to the contralateral side - was seen in the parietal region, ipsilateral to the stroke. Only modest changes were seen in the corresponding frequency power spectra, however. The authors suggest that the two different methods of analysis may well complement each other. ]

AFFILIATIONS

  1. Magyar Tudományos Akadémia Pszichológiai Intézete, Budapest
  2. Péterfy Kórház Idegosztály, Budapest
  3. Totts Gap Medical Research Laboratories, Bangor, USA

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