Electroencephalographic (EEG) Recording and Epilepsy Exam Questions with correct Answers

Electroencephalographic (EEG)
Recording and Epilepsy Exam

Epilepsy ii- iiAnswers ii-Recurrent iiseizures

-Problem iiusually iiwith ii*medial iitemporal iilobe-> iiHippocamus* ii

-2nd iimost iicommon iineurological iiproblem iiafter iistroke

EEG ii- iiAnswers ii-* iiElectroencephalogram*
-The iicollective iielectrical iiactivity iiof iithe iineurons iiin iithe iicortex ii(pyramidal iicells) iican
iibe iimeasured.


-The iiactivity iiof iithe iicortical iineurons iichanges iiin iiresponse iito iibehavioral iistates iiand ii
pathologies iisuch iias ii*coma iiand iiepilepsy* ii

-EEG iiis iiimportant iiin iithe iiclinical iiassessment iiof ii
*cortical iifunction*

-Brain iielectrical iiactivity iichanged iiwith ii*sleep iior iialtered iiattention*

Where iidoes iiEEG iicome iifrom? ii- iiAnswers ii-*Extracellular iifield iipotential ii(ECFP)* iiin
iithe iiISF ii(brain iiinterstitial iifluid)
-There iiare ii100s iiof iithese iithat iiget iiSUMMATED iitogether iito iihave iia iirecording iiyou
iirecognize ii(EEG)


EEG iiof iiseizure ii- iiAnswers ii-Position iiof iirecording iielectrode ii(location iiof iielectrode
iithat iimeasures iiVOLTAGE) iivs. iiOnset iiof iiseizure ii(time) ii


-Where iiis iithe iielectrode iiand iiwhere iiare iiyou iimonitoring iithe iibrain?
>Each iielect iiode iiis iimonitoring iiactivity iibetween ii2 iilocations
>F= iiFrontal
>Fp= iiPre-Frontal
>C= iiCentral iisulcus
>P= iiParietal
>O= iiOccipital ii

-From iiT=0 iito iiT=1: iiEEG iiamplitude iiis iifairly iiLOW

-After iiT=1: iiSee iiamplitude iion iievery iichannel iiis iihuge= iiSPIKES

, -Red iiline iion iigraph iiindicates iiABNORMAL iielectrical iiactivity iion iiright iiand iileft
iihemispheres iifrom iifront iito iiback= ii*Grand iiMal iiSeizure*: iiActing iion iiALL iichannels iiat
iian iiinstant iiof iitime
>Generalized iiseizure ii


-Odd ii#: iiLeft iiside

-Even ii#: iiRight iiside

-Certain iiarrangements= iiMONTAGE

Generation iiof iiextracellular iifield iipotentials ii(ECFP) ii- iiAnswers ii--Primary
iitransmembranous ii(synaptic) iicurrents ii(both iiinward iiand iioutward) ii
generate iisecondary iiionic iicurrents iialong iithe iicell iimembranes iiin iiboth iithe iiintra- iiand
iiextracellular iispaces ii(release iitransmitter)


-Single iineuron iielectrical iiactivity iiCANNOT iibe iirecorded iifrom iithe iiscalp ii(ECFP iiNOT
iimeasuring iione iineuron) ii


-Scalp iirecording iiis iithe iisummed iiextracellular iifield iipotentials iiof iilarge iinumbers iiof
iineurons. ii


-ECFPs iiare iiSLOWER iithan iiaction iipotentials iiand iican
SUMMATE

-The iiportion iiof iithe iicurrent iithat iiflows iithrough iithe iiextracellular iispace iiis iidirectly ii
responsible iifor iithe iigeneration iiof ii"extracellular iifield iipotentials" iirecorded iiat ii
the iiscalp iias iiEEG. ii

-Scalp iirecordings iidepend iion iithe iidepth iiof iisynaptic iiactivity iiand iithe iitype iiof ii
stimulation ii(IPSP iior iiEPSP)

-NEGATIVE iior iiPOSITIVE iiextracellular iifield iipotentials

NEGATIVE iiextracellular iifield iipotentials ii- iiAnswers ii-Recorded iiat iithe iiscalp iias ii
*UPWARD iiEEG iideflections* ii
-Current iiflow iiis iiinward ii*"sink"* iiand iiNEGATIVE ii
near iithe iiscalp.

POSITIVE iiextracellular iifield iipotentials ii- iiAnswers ii-Extracellular iifield iipotentials iiare
iirecorded iiat iithe iiscalp iias ii
*DOWNWARD iiEEG iideflections* ii
-Current iiflow iiis iioutward ii*"source"* iiand ii
POSITIVE iinear iithe iiscalp