# Off-line averaging to stimulus onset vs. response

**URL:** <https://mne.discourse.group/t/off-line-averaging-to-stimulus-onset-vs-response/33>\
**Category:** Mailing List Archive (read-only)\
**Tags:** list-archive\
**Created:** [March 20, 2008, 8:16pm UTC](https://mne.discourse.group/t/off-line-averaging-to-stimulus-onset-vs-response/33 "2008-03-20T20:16:21Z")\
**Posts on this page:** 1\
**Page:** 1

<div class="post-metadata">

**Author:** ![system](https://global.discourse-cdn.com/free1/uploads/mne/original/1X/85cc6bd2b69cb698a166dc6d880fb550510d0144.jpeg) [@system](https://mne.discourse.group/u/system)\
**Post date:** [March 20, 2008, 8:16pm UTC](https://mne.discourse.group/t/off-line-averaging-to-stimulus-onset-vs-response/33/1 "2008-03-20T20:16:21Z")

</div>

Hello,

I have a question about epoching using the off-line averaging process. Say I have an eventfile ?allevents.eve? that was created by saving ALL trigger line transitions in mne\_process\_raw. I have created a number of \*.ave files which are intended to create epochs around different subsets of the events specified in the allevents.eve file. I understand and see that the format of the \*.eve file is \<sample\>\<time\>\<from\>\<to\>. Where the event is defined as going from the \<from\> value to the \<to\> value.

So my allevents.eve file contains the following \<from\>\<to\> events, 0 to 10, 0 to 20, 0 to 30 (stimulus onset). It also contains the following events: 10 to 0, 20 to 0, and 30 to 0 (response).

I want to create averaged epochs around each of these six event types separately.

Consider the lock to stimulus onset case. In my \*.ave files, I specify the event file and the event. Consider the case where I want to epoch around events where the trigger line goes from 0 to 10. My ?trans0\_10.ave? file specifies:

eventfile allevents.eve

event 10

First question: is this specification doing what I think it is doing? That is, is it going through the allevents.eve file and only using those events for which the transition is from 0 to 10?

Second question: how do I specify, in another ave file, say ?trans10\_0.ave?, to only epoch around only the events that transition from 10 to 0?

I am a little confused on the two specifications of eventfile and event in the \*.ave file, and cannot quite figure it out from the manual. Sorry about that.

Thanks for any information provided!

Best Regards,

Linda Moya