PubMed Health⌕ Search

Biomedical subjects

R G Schmid

Publications and source records attributed to R G Schmid.

11 recordsLinked to original sources
PubMed2002

Correlation between spectral EEG parameters and intelligence test variables in school-age children.

OBJECTIVES: The objective of the study was to investigate the relationship between the degree of intelligence and spectral electroencephalographic (EEG) parameters and to find out which EEG variables are relevant for this correlation. METHODS: Bipolar 1 min EEG recordings were derived for the fronto-central and parieto-occipital leads from 155 clinically healthy 10-year-old children in vigilance state awake with eyes closed. Relative spectral power parameters were calculated by Fast Fourier Transform. Two-group t tests according to the score values of the 'WISC-R' intelligence test as well as univariate and multiple correlation analyses between spectral and intelligence test variables were carried out. RESULTS: A statistically significant positive correlation of the intelligence test variables with the spectral alpha power and a significant negative correlation with the spectral power of lower frequency bands was observed. Predicting the spectral parameters by means of intelligence test variables, significant multiple correlation coefficients were revealed in the frequency ranges: 0.5-1.5, 3.0-5.0 and 9.0-10.5 Hz. The highest significance (P<0.0001) was found for the spectral value at 9.0 Hz. CONCLUSIONS: The results of t tests and correlation analyses confirm the strong relationship between spectral EEG parameters and the degree of intelligence indicating that the 'EEG recordings do reflect intellectual abilities'. It may be supposed that the amount of the intelligence quotient is correlated with the degree of EEG maturation and thus reflects the active number of synapses and the degree of differentiation of the neuronal controlling system.

Alpha Rhythm↗
PubMed1997

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

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 parietooccipital 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.

Attention Deficit Disorder with Hyperactivity↗
PubMed1992

Comparative coherence studies in healthy volunteers and Down's syndrome patients from childhood to adult age.

Within the scope of the Munich Pediatric Longitudinal Study, EEG coherence was studied in 212 Down's syndrome patients and 342 healthy controls aged from 6 months up to 30 years. The digitalized EEG records were subjected to spectral analysis. Frequency band-related coherences were calculated to reveal age-specific differences in the functional relationship between two brain areas in Down's syndrome patients and controls. The results show that in the "eyes-open" state the intra-hemispheric coherence in the alpha band was significantly lower (P less than 0.05) in the Down's syndrome patients than in the controls whereas that in the delta bands it was generally higher. The intra-hemispheric coherence in the "eyes-closed" state was generally higher in the Down's syndrome groups than in the controls; however, significant differences could be detected only in some age groups. The age-specific development of coherence in the inter-hemispheric parieto-occipital region was almost identical in Down's syndrome children as in controls, both with open and closed eyes. The most distinct differences were found in the fronto-central inter-hemispheric coherence (P less than 0.01), while the coherence deficiencies in the Down's syndrome group became more prominent with increasing age from school age onwards. These electrophysiological results are compared with the results of neuropathological and neurophysiological studies of other authors. It can be suggested that there are correlations with a significantly small number of dendritic spines in Down's syndrome patients, which was determined in neuropathological examinations. A neuronal model of interpretation is presented which explains the increasing developmental deficit with age in Down's syndrome children.

Adolescent↗
PubMed1986

[Motor activity of the mouth and mouth therapy in cerebral palsy. Preliminary results in the treatment of neuromuscular disorders of the mouth in children with cerebral palsy using the Castillo-Morales concept].

56 patients suffering from connatal cerebral palsy were treated with removable orthodontic appliances possessing stimulation areas according to Castillo-Morales. The intention was to improve the well-known orofacial dysfunctions of these patients. The evaluation of a standard treatment schedule leads to the following statements: The tongue and lip control can be improved in many patients, as well as the chewing and swallowing pattern, the speech and the problem of saliva running out of the mouth. The resting-position of the tongue is normalized in some of the cases. The habit of an open mouth can hardly ever be improved. In a small number of patients some parameters of orofacial function worsened during treatment; in most of these cases, however, a general improvement of orofacial function justified further treatment with palatal plates.

Cerebral Palsy↗
PubMed1985

Z-transformed EEG power spectra of children with Down syndrome vs a control group.

Standardized EEG records of eighty-eight children with Down syndrome aged between six months and five years were analysed. The EEGs were digitalized, evaluated by spectral analysis, and subjected to z-transformation, a method which allows a direct comparison of the Down syndrome children with a normal control group (Munich Developmental Longitudinal Study). The results show a significant increase in absolute power, especially theta power; the absolute alpha power is less markedly increased or even decreased. The most significant differences, however, are observed when calculating the relative alpha power. Children with Down syndrome show a reduced relative alpha power already at the age of six months, and this reduction becomes even more prominent with growing age.

Child↗
PubMed1983

[Development of the electroencephalogram in children--comparison of visual and automatic evaluation].

EEGs were recorded of 399 normal children, age 6 months to 5 years, in the Munich Pediatric Longitudinal Study. In all age groups bipolar EEG derivations were recorded with eyes open; in 259 children (age 3, 4 and 5 years) also with closed eyes. The visual evaluation--using a computer adapted evaluation sheet--showed a dominant activity of 5.5 Hz in 6 months old children, of 9 Hz in 5 years old children (eyes open). The mean amplitudes of the dominant activity decreased by 10 microV during this time. With eyes closed the dominant activity in the parieto-occipital area showed an increase from 7.7 to 8.5 Hz. The amplitude of 40-50 microV in the parieto-occipital areas was higher than in the frontal and temporal areas (25-30 microV). Examination with spectral analysis showed a reduction of the relative power in the delta range from 77 to 69% with a simultaneous increase in the alpha range from 3 to 10%. The peak frequencies showed an age dependent development corresponding to the visual analysis. Under the condition eyes open, the mean values of peak frequencies showed an increase from 8.6 to 9.5 Hz in the fronto-central areas and from 8.5 to 9.4 Hz in the occipital areas. With eyes closed the increase of peak frequencies reached up to 0.6 Hz for the age of 4 to 5 years. Age classification is more exact with spectral parameters. Compared to visual parameters, up to 29% more children were classified in the correct age-groups by spectral parameters. As expected the recognition rates decreased in older children.

Cerebral Cortex↗