PSTH Versus Time

This analysis shows the dynamics of the perievent histogram over time. It calculates multiple PST histograms using a “sliding window” in time. Each histogram is shown as a vertical stripe with colors representing the bin counts. Horizontal axis represents the position of the sliding window in time.

Parameters

Parameter	Description
Reference	Specifies a reference neuron or event.
XMinPSTH	Histogram time minimum in seconds.
XMaxPSTH	Histogram time maximum in seconds
BinPSTH	Histogram bin size in seconds.
Start	Start of the first sliding window in seconds.
Duration	Duration of the sliding window in seconds.
Shift	How much sliding window is shifted each time.
Number of shifts	The number of sliding windows to be used.
Normalization	Histogram units (Counts/Bin, Probability or Spikes/Second). See Algorithm below.
No Selfcount	An option not to count reference events if the target event is the same as the reference event (prevents a histogram to have a huge peak at zero when calculating PSTH versus itself).
Sliding window axis direction	Direction of the sliding window axis (horizontal or vertical).
Sliding window axis alignment	Allows to specify what values are shown in the sliding window axis. There are two options: Start of Window and Center of Window. Suppose your data has the strongest correlation at 50 seconds. This means that the window that has 50 seconds as its center will show the highest PST 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.
Smooth	Option to smooth the histogram after the calculation. See Post-Processing Options for details.
Smooth Filter Width	The width of the smooth filter. See Post-Processing Options for details.
Send to Matlab	An option to send the matrix of numerical results to Matlab. See also Matlab Options.
Matrix Name	Specifies the name of the results matrix in Matlab workspace.
Matlab command	Specifies a Matlab command that is executed after the numerical results are sent to Matlab.
Send to Excel	An option to send numerical results or summary of numerical results to Excel. See also Excel Options.
Sheet Name	The name of the worksheet in Excel where to copy the numerical results.
TopLeft	Specifies the Excel cell where the results are copied. Should be in the form CR where C is Excel column name, R is the row number. For example, A1 is the top-left cell in the worksheet.

Summary of Numerical Results

The following information is available in the Summary of Numerical Results

Column	Description
Variable	Variable name.
Reference	Reference variable name.
YMin	PSTH minimum.
YMax	PSTH maximum.
Color Scale Min	PSTH minimum.
Color Scale Max	PSTH maximum.
Spikes	The number of spikes in the variable

Algorithm

NeuroExplorer calculates multiple PST histograms (see Perievent Histogram for more information on how each PSTH is calculated). Each histogram is calculated for a different interval (window) in time:

[window_start[i], window_end[i]], i = 1,...,Number_of_Shifts

That is, for each histogram only the timestamps that are within the window are used.

The following rules are used to calculate the windows:

window_start[1] = Start

window_end[1] = Start + Duration

window_start[2] = Start + Shift

window_end[2] = Start + Shift + Duration

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