Welcome to the FieldTrip website

FieldTrip is the MATLAB software toolbox for MEG, EEG and iEEG analysis, which is released free of charge as open source software under the GNU general public license.

Please cite the FieldTrip reference paper when you have used FieldTrip in your study.

Robert Oostenveld, Pascal Fries, Eric Maris, and Jan-Mathijs Schoffelen. FieldTrip: Open Source Software for Advanced Analysis of MEG, EEG, and Invasive Electrophysiological Data. Computational Intelligence and Neuroscience, vol. 2011, Article ID 156869, 9 pages, 2011. doi:10.1155/2011/156869.

To get started, head over to the getting started documentation and the tutorials.

Latest release

The latest code developments can be tracked in detail on GitHub.

26 November, 2020

FieldTrip version 20201126 has been released. See GitHub for the detailed list of updates and this news item than explains the issue and potential consequences for your analyses.

News and announcements

You can also follow us on Twitter.

27 November, 2020

Regretfully we identified a bug in FieldTrip releases starting from release 20200701 onward, which might have affected your results.

Specifically, if you have been using ft_sourceanalysis with DICS as a method, and if the order of the channels of the input data structure was not alphabetical, the results are incorrect. This is caused by an accidental alphabetical reordering of the channels in the cross-spectral density matrix, which was not reflected by a similar reordering in the leadfields. We are grateful to Alexandra Steina to help us identify and resolve it. See issue #1587 on GitHub for more information.

Are you affected? If you used a FieldTrip version between 20200701 and 20201126, and you used ft_sourceanalysis with method DICS, and your channels are not in alphabetical order, then you are likely affected. For CTF MEG data the channels are usually in alphabetical order. Neuromag/Elekta MEG data, and MEG data from other systems often have the channels not in alphabetical order. The same holds for EEG data, so your results are likely affected if you are working with EEG data, or non-CTF MEG data.

To resolve the problem, please update to the latest 20201126 release version from the FTP server or from the GitHub release page, recompute your source estimates, and your downstream results.

20 November, 2020

fNIRS is often used in freely moving subjects and in motion research. We implemented a FieldTrip example script that makes a movie of the fNIRS signal, motion capture, and video data together. The movie demonstrates the fNIRS signals and artifacts synchronously with video data during various movements, such as walking, turning, frowning, head movements and jumping. See https://www.youtube.com/watch?v=k1OB-vTWCys.

9 October, 2020

Robert presented two new features of FieldTrip on the online LiveMEEG 2020 conference. We now have the data2bids function to help you to organize your data in the BIDS structure and to share it. Best do this before you start doing your analysis, so that your analysis scripts can be shared along with the data or publication. Furthermore, all high-level FieldTrip functions now have the cfg.reproducescript option that allows you to create a tutorial-style analysis script of everything you do, regardless of how much your original code resembles a plate of spaghetti ;-)

The presentation includes a live demo and has been recorded; you can watch it on Crowdcast. The slides of the presentation are available on SlideShare.

17 September, 2020

We are changing our communication strategy, which is an integral part of our work! We will continue to use this website for news items and updates on releases, but we will also use Twitter more systematically and to the point. Instead of sending a tweet upon every commit (which made sense in the pre-GitHub days but not any more), we will start sending less frequent but more interesting tweets with important releases, announcements of new features, documentation updates, training events, and other interesting information! So to follow the important news, please keep checking here or follow us on Twitter.

01 July, 2020

In FieldTrip release 20200701 the low-level functions in fieldtrip/inverse have been renamed to ft_inverse_xxx and their input and output arguments have been cleaned up. This addresses a long-standing plan for improving the inverse modeling API. Except for the renaming of the low-level functions (which you won’t notice if you call them through the high-level ft_sourceanalysis and ft_dipolefitting) there are no functional changes.

24 June, 2020

We are sorry to report that with merging the recent pull request #1377 about a month ago, we introduced a bug in the FieldTrip release that might have affected your computations.

Specifically, the handling of the defaults for cfg.reducerank and the cfg.backproject changed a bit, which had an unforeseen sideeffect in ft_prepare_leadfield, if (and only if) you used this function for the computation of MEG-based leadfields, using the singleshell method. Specifically, ft_prepare_leadfield would by default compute MEG singleshell leadfields with reducerank=2 (this is how it always has been), but it would wrongly backproject (i.e. the intended projection of the rank-reduced 2-column leadfield back into 3D space with a column for the x, y, and z dipole moment in Cartesian space) the rank-reduced leadfield. Rather, ft_prepare_leadfield would on line 292 discard the last column. The error was due to MATLAB interpreting if [] as false, causing on line 295 only the first two columns to be copied to the output. Consequently, the leadfield for the z-direction was discarded.

Are you affected? If you used the master branch from GitHub (which is the development version), or a release version between 20200529 and 20200607, and if you have used ft_prepare_leadfield for MEG with singleshell models, then you are likely affected. You can check yourself: your precomputed leadfields should have three columns; if they only have two columns and you did not explicityly specify reducerank and backproject in your configuration, your leadfields are wrong. Other models than MEG singleshell are not affected.

To resolve the problem, please update to the latest 20200623 release version from the FTP server or from the GitHub release page and recompute your leadfields, source estimates, etcetera.

11 June, 2020

Robert and Jan-Mathijs have made an improvement to how color schemes can be specified. In functions supporting cfg.colormap, you can now also specify a subset of the color schemes that are in matplotlib, as well as the brewermap color schemes (e.g. ‘RdBu’). See ft_colormap for more information.

In this movie you can see Robert and Jan-Mathijs working on this. And finally, as a bonus, we have added an ‘ftcolors’ colormap, which will give your artwork this extra FieldTrippy feel. Happy plotting!