AnyWave:Delphos

Delphos, standing for Detector of ElectroPhysiological Oscillations and Spikes, is a detector based on the ZH0-normalization of the wavelet transform described above [Roehri et al., 2016]. Two separate interfaces were developed: Delphos and Delphos Viewer. The former is designed to run the detectors while the latter permits to review the detections and adjust parameters if needed. These plugins were used in three published papers [Roehri et al., 2017, Pizzo et al., 2017, Roehri et al., 2018].
Once the plugin starts, the user selects the channels and the duration of the recording to be analyzed as well as the type of events to be detected (oscillations given a certain frequency band and spikes) as illustrated in the figure below. He or she can also modify the wavelet oscillations and the detection parameters. If artifacts were previously marked in AnyWave, the user enters the name of the marker and Delphos discards the concerned sections. At the end of the detection, the main frame displays the rates per minutes of the detections on all selected channels as a bar plot.

This plugin was designed to be applied on many channels to give a global map of the interictal activities. On a computer with 32 GB of RAM and 12 cores, it takes Delphos (ver. 1.0) 10 min to analyze 100 to 120 channels of 5 min recording. To reach this speed, we parallelize the detection procedure according to the channels. In other words, each core launches the procedure on different channels. To avoid exceeding the available amount of RAM, Delphos cuts the data into several chunks of the same duration.

Every detection is automatically sent to AnyWave as color-coded marker, each color corresponding to different classes of oscillations or spikes. These markers can be used to review the detection in AnyWave or in Delphos Viewer. The results can be exported in an Excel or Matlab file.

There are also two experimental modules. One is made for the detection during the ictal period estimating the background preceding the seizure. The second outputs a kind of raster plot of the detections.