Studio Tutorial: Epoching and Baseline Correction - ucdavis/erplab GitHub Wiki

Now that the bin information is present, we can extract discrete epochs from the continuous EEG data. In this example, we will use an epoch of -200 to 800 ms (i.e., starting 200 ms before the time-locking event and extending for 800 ms after). We will also perform baseline correction at this point, using the voltage from -200 to 0 ms as the baseline.

To do this, make sure that 6_N400_filt_elist_bins is selected in the EEGsets panel, go to the Extract Bin-Based Epochs panel, and make sure it is set up as shown in the screenshot below.

Click Apply to run the function. You will then see the standard window for naming the EEGset that will be created by this operation. Click Okay to confirm the name of the new EEGset, which adds _be (“bin epoched”) to the end of the previous EEGset name.

You will now see 6_N400_filt_elist_bins_be in the EEGsets panel. As shown in the screenshot below, Epoched EEG is now selected at the top of the panel and the other EEGsets are grayed out. Many ERPLAB functions apply only to continuous EEG or only to epoched EEG, so you can only have one of these EEGset types selected at a given time. In addition, panels that work with only one of these types of data will be grayed out when that type of data is not selected in the EEGsets panel.

You’ll also notice that the EEG display looks a little different now. As shown in the screenshot, the window shows the data from 5 individual epochs, with an epoch number above each epoch (1, 2, 3, 4, or 5). Note that the time-locking event is at time zero in each event.

In addition, the event code for the time-locking event has been replaced with a string that shows both the bin number and the event code. For example, the event code for the first event is labeled B2(121), which indicates that the event belongs to Bin 2 and the original event code was 121. You can also see the response event code for each target epoch (if a response occurred within the time period of the epoch). Event codes that occurred outside of an epoch are no longer visible.

---

Previous Page	Next Page	🏠
◀️ BINLISTER	Artifact Detection ▶️	Home

Part 1	Part 2	Part 3	Part 4
General Overview	Filtering EEG	Plotting ERPs	Shifting Event Codes
Importing EEG Data	The EventList	ERP Information	Epoch Continuous EEG
Example Experiment	BINLISTER	Grand Average	Spectral Data Quality
Load and View Data	➡️ Epoch and Baseline	Bin Operations	Channels and Locations
	Artifact Detection	Filtering ERPs	Re-Sampling; Re-Epoching
	Averaging (ERPs)	Averaging (Channels)	Converting to CSD
	Artifact Correction	Channel Operations
	Interpolation	Measurement Tool