[FieldTrip] Query regarding extraction of amplitude and latency
Tineke Snijders
T.M.Snijders at tilburguniversity.edu
Fri Jan 12 14:46:30 CET 2024
Hi Mathew,
For extracting amplitude values from a pre-specified time-window you can also use ft_selectdata to select means over a specific time-window / channels (or frequency).
E.g.
cfg=[];
cfg.channel={'F7','F3','FC5'}; %adjust to electrodes of interest, can also be 'all'
cfg.avgoverchan='yes';
cfg.avgovertime='yes';
cfg.latency=[0.3 0.5];
Avg300500_grand_erpLF=ft_selectdata(cfg,grand_erp);
You can do that on individual ERPs or on grand averages (with keepindividual='yes'), and then you can save the relevant numbers to a file using standard matlab code as Jan-Mathijs suggested.
Kind regards,
Tineke
-----Original Message-----
From: fieldtrip <fieldtrip-bounces at science.ru.nl> On Behalf Of fieldtrip-request at science.ru.nl
Sent: Friday, January 12, 2024 12:00 PM
To: fieldtrip at science.ru.nl
Subject: fieldtrip Digest, Vol 158, Issue 5
Send fieldtrip mailing list submissions to
fieldtrip at science.ru.nl
To subscribe or unsubscribe via the World Wide Web, visit
https://mailman.science.ru.nl/mailman/listinfo/fieldtrip
or, via email, send a message with subject or body 'help' to
fieldtrip-request at science.ru.nl
You can reach the person managing the list at
fieldtrip-owner at science.ru.nl
When replying, please edit your Subject line so it is more specific than "Re: Contents of fieldtrip digest..."
Today's Topics:
1. European Society for Cognitive and Affective Neuroscience -
May 2024 - Ghent, Belgium (CASPAR Emilie)
2. Normalization of timelocked average LFP amplitude (voltage)
(Zheng, Ning)
3. Re: Query regarding extraction of amplitude and latency
values (Varghese Mathew 1881002)
----------------------------------------------------------------------
------------------------------
Message: 3
Date: Fri, 12 Jan 2024 09:11:10 +0530
From: Varghese Mathew 1881002
<varghese.mathew at res.christuniversity.in>
To: FieldTrip discussion list <fieldtrip at science.ru.nl>
Subject: Re: [FieldTrip] Query regarding extraction of amplitude and
latency values
Message-ID:
<CAFnh8hJPVj62qZfiXTRpsebaKFvJnojEhh0dBvs0OYxPodRBow at mail.gmail.com>
Content-Type: text/plain; charset="utf-8"
Thank you for the reply. This gave me good clarity.
Sincerely
Varghese Mathew
On Wed, Jan 3, 2024 at 3:32 PM Schoffelen, J.M. (Jan Mathijs) via fieldtrip <fieldtrip at science.ru.nl> wrote:
> Hi Mathew,
>
> If you want to extract amplitude values from a pre-specified time
> window, I would just compute the average ‘by hand’, i.e. take the mean
> (across the relevant dimension of the matrix) from a subselection of
> time points. If you want to extract the latency of a peak, and then
> use the amplitude corresponding to that peak, I would use MATLAB’s
> findpeaks function (or some other heuristic), and use the amplitude
> values that correspond to the identified peaks. This requires some
> ‘plain’ matlab coding, there’s no FieldTrip functionality that gives you such results directly.
>
> Good luck with your analysis,
> Jan-Mathijs
>
>
> On 29 Dec 2023, at 04:30, Varghese Mathew 1881002 via fieldtrip <
> fieldtrip at science.ru.nl> wrote:
>
> Hi
> I am a Ph.D. scholar working on face processing studies. I am
> currently trying to use the Fieldtrip toolbox for doing ERP analysis.
> I am able to plot the ERP and topo plots. I would like to know if
> there is a way to extract amplitude and latency values from different
> time windows of interest, to conduct statistical analysis in another software.
> I'm really looking forward to any leads.
>
> Thanks in advance
> --
> Varghese Mathew
> Ph.D Scholar
> CHRIST (Deemed to be university)
> Bangalore-29
> _______________________________________________
> fieldtrip mailing list
> https://mailman.science.ru.nl/mailman/listinfo/fieldtrip
> <https://eur01.safelinks.protection.outlook.com/?url=https%3A%2F%2Fmai
> lman.science.ru.nl%2Fmailman%2Flistinfo%2Ffieldtrip&data=05%7C02%7Cfie
> ldtrip%40science.ru.nl%7C0b6be21d96244624897f08dc0c42c4b5%7C084578d940
> 0d4a5aa7c7e76ca47af400%7C1%7C0%7C638398728119764744%7CUnknown%7CTWFpbG
> Zsb3d8eyJWIjoiMC4wLjAwMDAiLCJQIjoiV2luMzIiLCJBTiI6Ik1haWwiLCJXVCI6Mn0%
> 3D%7C3000%7C%7C%7C&sdata=KTSx3724BFj4CGwPShTfh1pd8X9uYYxnacuea08eKCk%3
> D&reserved=0>
> https://doi.org/10.1371/journal.pcbi.1002202
>
>
> _______________________________________________
> fieldtrip mailing list
> https://mailman.science.ru.nl/mailman/listinfo/fieldtrip
> https://doi.org/10.1371/journal.pcbi.1002202
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mailman.science.ru.nl/pipermail/fieldtrip/attachments/20240112/e535eb0e/attachment-0001.htm>
------------------------------
Subject: Digest Footer
_______________________________________________
fieldtrip mailing list
https://mailman.science.ru.nl/mailman/listinfo/fieldtrip
_______________________________________________
fieldtrip mailing list
https://mailman.science.ru.nl/mailman/listinfo/fieldtrip
https://doi.org/10.1371/journal.pcbi.1002202
------------------------------
End of fieldtrip Digest, Vol 158, Issue 5
*****************************************
More information about the fieldtrip
mailing list