C:\Users\katulka\Desktop\EEG\EEGram.png
XLIII. Electroencephalography
XLIV. Evoked potentials
Dep. of Physiology, Fac. of Medicine, MU, 2016 © Kateřina Fialová

Electroencephalography (EEG)
•method used for the registration of electrical potentials of the brain
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•Hans Berger (1929)
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•scalp EEG
•electrocorticogram (ECoG)
•stereoelectroencephalogram (SEEG)
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•macro EEG
•micro EEG
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Electroencephalography
•placement of electrodes: system 10 - 20
C:\Users\katulka\Desktop\EEG\systém 10 20 č.2.png

Electroencephalography
•attachment  of electrodes during scalp EEG
C:\Users\katulka\Desktop\EEG\čepice - dreamstime.com.jpg
www.dreamstime.com

Electroencephalography
•alpha rhythm: frequency 8-13 Hz, noticeable with eyes closed, in awake, healthy and mature brain,
especially in parietooccipital lobes •beta rhythm: frequency 14-30 Hz, noticeable with open eyes,
sometimes constantly over frontal area. Phenomenon of suppression of the alpha rhythm by opening
eyes – alpha attenuation reaction (AAR). •theta rhythm: frequency 4-7 Hz, noticeable in children,
in healthy adult only during waking sleep stages •delta rhythm:   frequency 1-3 Hz, in neonates and
infants, in healthy adults only during deep non-REM sleep
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Electroencephalography
•EEG waves
C:\Users\katulka\Desktop\EEG\EEG vlny.jpg

Electroencephalography
•EEG record - example
C:\Users\katulka\Desktop\EEG\EEGram.png

Evoked potentials (EP)
•electrical manifestation of brain activity triggered by external sensory stimulus
•evaluation of the functional state of the nerve pathway
•TYPES OF EP:
VEP (visual)
AEP (auditory)
SEP (somatosensoric)
MEP (motoric)
SSEP (stable)
ERP (cognitive)
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Evoked potentials
•wave p300 (mean latency 300ms)
C:\Users\katulka\Desktop\EEG\EP.jpg