Sözel Görev Esnasında Beyin Asimetrisine Spektral EEG ile Yaklaşım*

Year 1993, Volume: 46 Issue: 2, 269 - 279, 30.06.1993

Erhan Nalçacı

Abstract

56zel gérev ile olusturulan zihinsel gorilim esnasinda serebral kortikal fonksiyonlarin asimetrisinin spektral EEG ile saptanmasi amagland.
Saglhkh 20-30 yas arasi, 14 denekte el tercihi belirlendi. Sag ve soltemporal bolgelerden alinan EEG kayitlari, spektral gii¢ analizi ile degerlendi. Dinlenim kaydi yanisira sdézel belleZe dayanan iki farkh gérev esnasinda kayit alindi. Testler arasindaki ortalama spektral giic farklihklan, delta, teta, alfa ve beta bandlarinda istatistiksel olarak
degerle nda spektral gticlin mutlak ve goreceli degerlerinde, alfa bandindan beta bandina kayma gézlendi. Bu kayma sol hemisferde sag hemisfere gére daha biiytiktii. El tercihi ile sol -eksisag hemisfer farkhhklari arasinda zayif bir korelasyon vardi, Sunulan caligma, sol -eksi- sag ortalama spektral gti¢ grafiklerinin serebral asimetrinin gésterilmesinde kuilanilabilecegini telki etti,

Keywords

Serebral korteks , Lateralizasyon , EI tercihi , Serebral dominans , Elektroensefalografi , Alfa Ritmi , Beta Ritmi.

Ethical Statement

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Supporting Institution

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Project Number

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Thanks

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An Approach To Cerebral Asymmetry During Verbal Task By Using Spectral EEG

Abstract

The aim of this research is to evaluate the asymmetry of cerebral cortical functions using quantitative EEG during mental tension induced by assigned verbal task.
The hand preferences of 14 healty subjects, who were between the ages of 20-30, were assessed. The EEG records taken from right and
left temporal regions during two different tasks related with verbal memory and during resting period were analyzed and spectral power was computed. The average spectral power differences among the tests were statistically evaluated for the bands of delta, teta, alfa and beta. For each subject left-minus-right average spectral power graphics were obtained. It was observed that during a verbal task, there was a tendency from alfa band to beta band in the relative and absolute values of the spectral power. This tendency was more pronounced in the left hemisphere in comparison to right hemisphere, There was a weak correla- tion between hand preferences and left-minus-right hemisphere differences, Presented study suggests that the left -minus- right average spectral power graphics can be used in displaying cerebral asymmetry.

Keywords

Cerebral cortex , Laterality , Handedness , Cerebral dominance , Electroencephalography , Alpha rhythm , Beta rhythm.

Project Number

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