Average, different epoch size

One more quick question - when I get to the step of importing the file to the database, I'm able to select the different event groups, but it will not allow me to change the epoch time. And when I try to compute the average, it fails and says some trials are different durations. However, when viewing events from the main brainstorm page (with event times and duration), they all seem to be the same duration (~ 5 sec). Is there another step I'm missing where I can make the trial epochs all the same?

Thanks again!

Hi Ann,

Are you importing the epoched data, or reviewing the raw data and then import to Brainstorm?

If you do the second, it is possible to define the epoch length with respect to a given trigger, thus ensuring that all epochs have the same length.

The error you describe seems to be caused as not all epochs have exactly the same number of samples. Please put the entire error message, so we can identify better what is going on. Also add screenshots that are relevant so we can understand better your situation.

P.S. Keep one topic per thread, so other users can find easily find answers

Hi -

Sorry for mixing up topics, but they are all related to NIRS data import and processing, so I thought they were together.

I am reviewing the raw data and then importing to Brainstorm (using right-click, import to database, same as the tutorial) but with my own data. The option to define the epoch time is grayed out, regardless of which event group I select.

It won't let me upload 2 images, so I'll send a second post.

If I continue to import one of the events and then try to average, I get the following error.


I'm sure I'm just missing a step or doing them in the wrong order. Thanks again!

Before importing the epochs. Plot the time series so the Record tab is populated with the event information and verify that the events 1 have exactly the same length (as they are extended events).

If they are not the same length. You can change the extended events to simple (in the Event menu) and then import using the event 1 specifying how much data before or after the event you want to import. Then all the imported epochs will have the same length