User manual

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Fig. 4.11.2.1. Detection of extracellular synaptic waveform parameters (DC Baseline, Peak Amplitude
and Slope).
The Auto/Pos/Neg field determines whether the peak will be Automatically (Auto) determined to be
positive or negative, forced to be Positive (Pos), or forced to be Negative (Neg). The normal value is A,
automatic. Automatic calculates whether the average of the points between the Peak: ___ to ___ms after
pulse time fields is more positive than the baseline average value. If so, the peak is positive; otherwise the
peak is negative.
4.11.3 Latency
Latency is now measured only at 100% of Peak, and is therefore Peak Latency. Peak Latency is the time
between the occurrence of stimulus pulse and the peak. In later versions, Latency will be able to be
determined as a % of peak.
4.11.4 Slope
The Slope is calculated by taking all the waveform voltage/current points from the slope beginning time
point to the slope end time point, and using these points to calculate a linear regression line (least
squares fit) through the data.
When analyzing the Slope of the EPSP/EPSC there are several ways to determining the slope beginning
time point and the slope end time point. These Slope Calculation Methods are chosen by using the menu
commands:
AmpFile -> Slope calculation method...
to bring up the Slope Calculation Methods dialog box with the following choices (Fig. 4.11.4.1).