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EventRelatedSpectralPerturbation

A meta-node that segments and calculates the ERSPs for a predefined set of event markers.

Uses the following nodes: SelectRange, Segmentation, Spectrogram, FrequencyNormalization, ToDecibels, Rereferencing, Mean. More Info... Version 1.0.1

Ports/Properties

data

Data to process.

  • verbose name: Data
  • default value: None
  • port type: DataPort
  • value type: Packet (can be None)
  • data direction: INOUT

spectogram_subwindow_length

Length of the sub-windows for spectral estimation, in seconds. This node will extract successive windows from the given data of this length, which are overlapped according to the overlap samples parameter. Longer windows will give a higher-resolution spectrum, but at the same time the result will increase the smoothness (i.e., blurriness) along the time axis. The tradeoff between time resolution and frequency resolution that can be adjusted via this parameter is fundamental.

  • verbose name: Spectogram Subwindow Length
  • default value: 0.5
  • port type: FloatPort
  • value type: float (can be None)

spectrogram_overlap

Overlap between successive sub-windows, expressed as a fraction of the sub-window length. This determines by how much successive sub-windows are overlapped. Using a higher value will yield finer stepping in time without a change in temporal or frequency detail (since the time axis will be correspondingly more smooth to counter the finer stepping). If not given, defaults to half of the sub-window length. Can also be expressed in samples.

  • verbose name: Spectrogram Overlap
  • default value: 0.95
  • port type: FloatPort
  • value type: float (can be None)

spectogram_fft_size

Length of the FFT used, in samples. Using a higher number will yield a finer stepping along the frequency axis, without a change in frequency or temporal detail (the frequency axis will be correspondingly more smooth to counter the finer stepping). If not given, it defaults to the sub-window length.

  • verbose name: Spectogram Fft Size
  • default value: 256
  • port type: IntPort
  • value type: int (can be None)

spectogram_unit

Unit in which the sub-window length is expressed. By default this is seconds, but samples can also be used if necessary.

  • verbose name: Unit Used For Sub-Window Length.
  • default value: seconds
  • port type: EnumPort
  • value type: str (can be None)

frequency_normalization_alpha

The exponent of 1/f^alpha used in the correction. Set to None to determine the value automatically.

  • verbose name: Frequency Normalization Alpha
  • default value: 1.0
  • port type: FloatPort
  • value type: float (can be None)

time_bounds

Time range in seconds relative to the event, within which data will be selected to represent the individual trials. Express in this format: -1.5, 2 (will select from 1.5 seconds before the event to 2 seconds after).

  • verbose name: Time Bounds
  • default value: [-0.2, 0.6]
  • port type: ListPort
  • value type: list (can be None)

frequency_range

Frequency range for which to plot the ERSP.

  • verbose name: Frequency Range
  • default value: 1...45
  • port type: Port
  • value type: object (can be None)

baseline_removal_range

Reference time range relative to the event for removing the baseline.

  • verbose name: Baseline Removal Range
  • default value: -0.5...0
  • port type: Port
  • value type: object (can be None)

skip_baseline_removal

Skip baseline removal (performed later.)

  • verbose name: Skip Baseline Removal
  • default value: False
  • port type: BoolPort
  • value type: bool (can be None)

max_gap_length

Maximum length of time-stamp gaps that are allowed in segments. If a gap between successive samples is larger than this duration in seconds, then the affected segment is not extracted. Optional. Note that if your time stamps are jittered, this will generate a lot of false positives unless you use a very generous cutoff. You can use the DejitterTimestamps node early during your processing to fix that.

  • verbose name: Max Gap Length
  • default value: 0.2
  • port type: FloatPort
  • value type: float (can be None)

channel_range

Comma separated list of channels/ROIs for which an ERSP plot will be generated. Leave blank or set to 'all' to generate ERSP plots for all previously-selected channels/ROIs.

  • verbose name: Channel Range
  • default value: :
  • port type: Port
  • value type: object (can be None)

output_measure

Output measure to calculate. Mean will be the usual average ERP, while median and trim_mean result in estimates that are more robust to outliers. For moderate artifact content, trim_mean is preferable, and median should only be used for extremely contaminated data. The trials mode will return the raw trials instead of taking the mean, for averaging later using the GroupedMean for example.

  • verbose name: Output Measure
  • default value: trials
  • port type: EnumPort
  • value type: str (can be None)

cache_spectrogram

Enable caching for Spectrogram. This will significantly speed up re-use of the same data.

  • verbose name: Cache Spectrogram
  • default value: False
  • port type: BoolPort
  • value type: bool (can be None)

set_breakpoint

Set a breakpoint on this node. If this is enabled, your debugger (if one is attached) will trigger a breakpoint.

  • verbose name: Set Breakpoint (Debug Only)
  • default value: False
  • port type: BoolPort
  • value type: bool (can be None)

metadata

User-definable meta-data associated with the node. Usually reserved for technical purposes.

  • verbose name: Metadata
  • default value: {}
  • port type: DictPort
  • value type: dict (can be None)