Perievent spectrograms – Multichannel Systems NeuroExplorer User Manual
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2.34. Perievent Spectrograms
This analysis captures the frequency content of continuous variables or neuronal rate histograms in
the time windows around reference events.
Parameters
Parameter
Description
Reference
Reference event.
Max. Freq.
Maximum frequency for the spectrograms. If at least one continuous
variable is selected, the value of the Maximum Frequency parameter is set
as 0.5*Digitizing frequency of the first selected continuous variable. All
continuous variables selected for this analysis should have the same
digitizing rate.
Number of Fr. Values
Number of frequency values.
Normalization
Spectrum units (Raw PSD (Power Spectral Density), Log of PSD).
Start
Start of the first window (relative to the reference event).
Shift
How much sliding window is shifted each time.
Number of Shifts
total number of sliding windows.
Show Freq. From
An option to show a subset of frequencies. Specifies minimum frequency
to be displayed.
Show Freq. To
An option to show a subset of frequencies. Specifies maximum frequency
to be displayed.
X Axis
Allows to specify what values are shown in the sliding window X axis.
There are two options: Start of Window and Center of Window.
Suppose your data has the strongest spectral value at 50 seconds. This
means that the window that has 50 seconds as its center will show the
highest spectrum values. If the window width is 20 seconds, it will be the
window [40,60]. If you are using 'Start of window' option, you will see the
peak at 40 instead of 50 seconds. However, with 'Center of window' option,
the peak will be at 50 seconds.
Select Data
If Select Data is From Time Range, only the data from the specified (by
Select Data From and Select Data To parameters) time range will be used
in analysis. See also
.
Select Data From
Start of the time range in seconds.
Select Data To
End of the time range in seconds.
Interval filter
Specifies the interval filter that will be used to preselect data before
analysis. See also
Smooth
Option to smooth the spectrum after the calculation. See
for details.
Smooth Filter Width
The width of the smooth filter. See
for details.
Add to Results / Bin left An option to add an additional vector (containing a left edge of each
frequency bin) to the matrix of numerical results.
Add to Results / Bin
middle
An option to add an additional vector (containing a center of each
frequency bin) to the matrix of numerical results.
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