Export Connectivity Results

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Module information
Modules BESA Connectivity
Version BESA Connectivity 1.0 or higher

BESA Connectivity provides export of connectivity results via the menu entry ExportExport ResultsExport Connectivity Data. This option will export the entire connectivity matrix (for all latencies and frequencies) of the currently selected connectivity method, time-frequency decomposition method and condition.

BESA Connectivity Selected Connectivity and Time-Frequency Methods.png

The connectivity matrix is written in a simple ASCII file that can be opened and edited with a text editor (e.g.: Notepad). The extension .conn will be added. The first line of the connectivity results file format is a comma-separated list of information on the expoted data. It contains the following key - value pairs:

Key Value Description
VersionNumber 1.0 File format version
DataType Coherence / Granger Causality, etc. Connectivity method
DecompositionType Complex Demodulation / Wavelet Transform / Multitapering Time-frequency method
ConditionName Stimulus condition Name of condition
NumberTrials 12 Number of trials
NumberTimeSamples 120 Number of latencies
TimeStartInMS -400.0000 Start latency in [ms]
IntervalInMS 50.0000 Latency spacing in [ms]
NumberFrequencies 31 Number of frequencies
FreqStartInHz 2.000 Start frequency in [Hz]
FreqIntervalInHz 1.000 Frequency spacing in [Hz] (only relevant for complex demodulation)
Frequencies 4.00;4.47;4.98;... The frequencies used (only used for wavelets and multitapers)
NumberChannels 64 Number of channels/sources

The second line defines the channel/source labels. Please note that the list is comma-separated, therefore the list of labels must not contain spaces!

Example header
Complex Demodulation based Connectivity Analysis

VersionNumber=1.0 DataType=Coherence DecompositionType=Complex Demodulation ConditionName=Condition 1 NumberTrials=10 NumberTimeSamples=33 TimeStartInMS=-400.0000 IntervalInMS=50.0000 NumberFrequencies=31 FreqStartInHz=2.0000 FreqIntervalInHz=1.0000 NumberChannels=3 
ACsR_RC0 ACsL_RC0 PrM_RC0

Wavelet or Multitaper transformation based Connectivity Analysis

VersionNumber=1.0 DataType=Coherence DecompositionType=Multitapering ConditionName=Condition 1 NumberTrials=10 NumberTimeSamples=33 TimeStartInMS=-400.0000 IntervalInMS=50.0000 NumberFrequencies=5 FreqStartInHz=2.0000 FreqIntervalInHz= Frequencies=2.00;2.23;2.48;2.76;3.00; NumberChannels=3 
ACsR_RC0 ACsL_RC0 PrM_RC0

After the file header, the connectivity data is exported column-wise as indicated in the following image:

BESA Connectivity Data Blocks.png

The columns of each data block indicate the latencies, starting with the earliest latency (first column) up to the latest latency (last column). There should be as many columns in each data block as specified in the header by the value of the NumberTimeSamples key. The rows of each data block indicate the frequencies, starting with the lowest frequency (first row) up to the maximum frequency (last row). There should be as many rows in each data block as specified in the header by the value of the NumberFrequencies key.