Correlation of developmental neurological findings with spectral analytical EEG evaluations in pre-school age children

Abstract

For the differentiation of developmental neurological disorders in pre-school age children, the relationship between automatically derived EEG parameters and developmental neurological findings was investigated. Within the scope of the Munich Pediatric Longitudinal Study, the sample sets of 4- and 5-year-old children (according to the frontal and parieto-occipital EEG derivations) with selected abnormal findings categorized by special items were compared with the corresponding control groups. This was carried out by means of one-sided t tests and relative frequency band-related as well as single-step spectral power parameters in the alpha range of the EEG. Automatic analysis using single-step power values was superior to that using band-related parameters. This led to the conclusion that use of age-specific single-step parameters for a quantitative EEG analysis and ignoring the classical frequency bands will yield statistically greatly improved results. For 4- and 5-year-old children, the best separation of the neurologically abnormal groups from the normal control groups was obtained using relative spectral values in the frequency range of 9.0–9.8 Hz with a maximum at 9.4 Hz. At the same time, the topographical conditions of brain immaturation should be taken into account. The results for the children examined in this study differ in a stronger distinction over the frontocentral brain region of 4- and 5-year-olds ( P<0.01) and through an additional distinction over the parieto-occipital region of the 5-year-olds ( P<0.001). It still must be tested whether the spectral parameter at 9.4 Hz is age-specific for 4- and 5-year-old children or whether in other age groups different spectral parameters are of use. As an examiner-independent method, the automatic EEG analysis should become an integral component of developmental neurological diagnostics.