Incorrect epoch time when importing database

[tmcentanni]

I am working to import trial data from EEG (.mff raw file type). I have the epoch time set as [-200 to 4000 ms] but it's cutting off all trials at 1 second regardless of how I adjust this setting. I've never seen this issue before, so any help you can offer would be greatly appreciated!

Edit. Improved screenshot

[Raymundo.Cassani]

Hi @tmcentanni,

The behaviour you see is related to the type of events. Your events are extended (thus the [ext] in their name). As such when importing, the epoch times (-200-4000ms) are ignored. The duration of the events is used instead (which I assume is 1 s).

The solution is in a previous post

@Raymundo.Cassani

Solution
Change your events from extended to simple (point) events.

• Open your raw file, then in the Event section of the Recording tab, select your Event groups
• Go to the menu, Events > Convert to simple event
• Here, you may want to select Start. So the simple event will be located at the beginning of the extended event, i.e, at time 0.
• Close the figure to save the changes in the Events
• Then proceed to import, and you should be able to set the Epoch time to -1000-2000ms or the desired values

[tmcentanni]

Ah yes that makes sense - thank you!