Topographic aspects of photic driving in the electroencephalogram of children and adolescents
Braz. j. med. biol. res
;
37(6): 879-891, Jun. 2004. ilus, graf
Article
in English
| LILACS, BVSAM
| ID: lil-359905
RESUMO
The electroencephalogram amplitude spectra at 11 fixed frequencies of intermittent photic stimulation of 3 to 24 Hz were combined into driving "profiles" for 14 scalp points in 8 male and 7 female normal subjects aged 9 to 17 years. The driving response varied over frequency and was detected in 70 to 100 percent of cases in the occipital areas (maximum) and in 27 to 77 percent of cases in the frontal areas (minimum) using as a criterion peak amplitude 20 percent higher than those of the neighbors. Each subject responded, on average, to 9.7 ñ 1.15 intermittent photic stimulation frequencies in the right occipital area and to 6.8 ñ 1.97 frequencies in the right frontal area. Most of the driving responses (in relation to the previous background) were significant according to the spectral F-test (a = 0.05), which also detected changes in some cases of low amplitude responses not revealed by the peak criterion. The profiles had two maxima in the alpha and theta bands in all leads. The latter was not present in the background spectra in the posterior areas and was less pronounced in the anterior ones. The weight of the profile theta maximum increased towards the frontal areas where the two maxima were similar, while the profile amplitudes decreased. The profiles repeated the shape of the background spectra, except for the theta band. The interhemispheric correlation between profiles was high. The theta driving detected in all areas recorded suggests a generalized influence of the theta generators in prepubertal and pubertal subjects.
Full text:
Available
Index:
LILACS (Americas)
Main subject:
Photic Stimulation
/
Electroencephalography
/
Evoked Potentials, Visual
/
Functional Laterality
/
Occipital Lobe
Limits:
Adolescent
/
Child
/
Female
/
Humans
/
Male
Language:
English
Journal:
Braz. j. med. biol. res
Journal subject:
Biology
/
Medicine
Year:
2004
Type:
Article
Affiliation country:
Brazil
Institution/Affiliation country:
Fundação Oswaldo Cruz/BR
/
Universidade Federal do Rio de Janeiro/BR
Similar
MEDLINE
...
LILACS
LIS