Hi Ola, The moving average sampling that Jan-Mathijs described is in the rMEG Source-level Processing Pipelines section of the Reference Manual on pp. 141-146 of the 1200 Subjects Release version, and on pp.129-134 in the 900 Subjects version.
Best, Jenn Jennifer Elam, Ph.D. Scientific Outreach, Human Connectome Project Washington University School of Medicine Department of Neuroscience, Box 8108 660 South Euclid Avenue St. Louis, MO 63110 314-362-9387<tel:314-362-9387> e...@wustl.edu<mailto:e...@wustl.edu> www.humanconnectome.org<http://www.humanconnectome.org/> ________________________________ From: hcp-users-boun...@humanconnectome.org <hcp-users-boun...@humanconnectome.org> on behalf of Jan Mathijs Schoffelen <jm.schoffe...@gmail.com> Sent: Wednesday, October 25, 2017 3:13:30 AM To: hcp-users@humanconnectome.org Subject: Re: [HCP-Users] Source-MEG Resting state data Dear Ola, The information you are looking for is described in the 900 Subjects Release reference manual (somewhere on page 93-104). The band-limited power envelopes at source level have been sampled at a frequency of approximately 50 Hz (i.e. one estimate per 20 ms). The restingstate runs during MEG acquisition were about 5 minutes in length, which amounts to ~15.000 samples. Best wishes, Jan-Mathijs J.M.Schoffelen, MD PhD Senior Researcher, VIDI-fellow - PI, language in interaction Telephone: +31-24-3614793 Physical location: room 00.028 Donders Centre for Cognitive Neuroimaging, Nijmegen, The Netherlands On 24 Oct 2017, at 20:14, Ola Choukair <ola.chouk...@gmail.com<mailto:ola.chouk...@gmail.com>> wrote: Hi, As I was exploring your data, especially the Source-MEG time series, I noticed the time-series’ length is 14960 pts for each vertex. However, at the channel-level analysis, the time series are of 140 000 pts, with fs of 1034 Hz. I would like to know why the number of points at the source -level is so low. Has the signal been trunkated to cover less time of the resting state session or has there been another downsampling or both? I was not able to find that information anywhere in the HCP documentation. Thank you for your time, Ola Choukair MSc. Neurosciences U de Montréal _______________________________________________ HCP-Users mailing list HCP-Users@humanconnectome.org<mailto:HCP-Users@humanconnectome.org> http://lists.humanconnectome.org/mailman/listinfo/hcp-users _______________________________________________ HCP-Users mailing list HCP-Users@humanconnectome.org http://lists.humanconnectome.org/mailman/listinfo/hcp-users _______________________________________________ HCP-Users mailing list HCP-Users@humanconnectome.org http://lists.humanconnectome.org/mailman/listinfo/hcp-users
