The HBI reference (normative) database includes multi-channel EEG recordings in the following groups:
- children/adolescents: age 7-17 (n=300)
- adults: age 18-60 (n=500)
- seniors: age 61+ (n=200)
Inclusion/exclusion criteria presume an uneventful perinatal period, no head injury with cerebral symptoms, no history of neurological or psychiatric diseases, no convulsions, normal mental and physical development, and average or better grades in school. A 19-channel EEG is recorded in two resting conditions with eyes open (minimum 3 minutes), eyes closed (minimum 3 minutes), and five different task conditions, including two stimulus GO/NOGO tasks, arithmetic and reading tasks, auditory recognition and auditory oddball tasks. The characteristics of QEEG are normalized. The mean values and standard deviations for separate age groups are obtained. Deviations from “normality” are assessed by computing zscores – standardized measures of deviation of individual EEG parameters from the normative data.