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What is EPSP slope ? - (Jun/05/2013 )

And why not using EPSP amplitude ? When they measure LTP they always use EPSP slope why is that and what is it ? Also what is EPSP spike compared to amplitude and slope ?



it is more convincing to show both, amplitude and slope, because each parameter can change independenty from the other but in the case of LTP both should be increased

-Inmost sun-

The EPSP slope in an extracellular field recording is usually taken as the first one-third of the fEPSP. The slope value is preferred over the amplitude or other measures because at a higer current intensity (or if the electrodes are places too close to the cell bodies), the pEPSP is likely to be contaminated by the occurance of a pop spike and that can change the amplitude but not the slope.

-Mahati Krishna-

Also what is EPSP spike(1) compared to amplitude(2) and slope(3)?
1.- The signal seen when a large population of neurons fires simultaneously is the population spike.
2.- Amplitude is determined as the maximum amplitude (not necessary at the population spike).
3.- The slope beginning as soon as the EPSP slope becomes linear. The end of slope measurement is before it begins to asymptote toward the peak (i.e. when it stops being linear), or before any secondary phase of slope begins. 

-Cainosito Cainositas-

I do not agree that slope of EPSP is preferred towards amplitude; commonly, it is the other way around; so it is totally okay to present only the amplitude; the term "spike" is usually used in terms of action potentials rather in terms of EPSP´s

-Inmost sun-