<HTML><BODY style="word-wrap: break-word; -khtml-nbsp-mode: space; -khtml-line-break: after-white-space; "><DIV>Hi</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>I have been trying out the various methods as discussed and have come across a problem. </DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>When I select cfg.singletrials = 'yes' I get a number of error messages saying</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">error(<FONT class="Apple-style-span" color="#A020F0">'this option contains a bug, and is therefore not supported at the moment'</FONT>);</DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>I am using the toolbox <FONT class="Apple-style-span" face="Lucida Grande">fieldtrip-20060516. </FONT></DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>I noticed however, if I select cfg.rawtrials = 'yes' the function will run. </DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Can you help. </DIV><DIV><BR class="khtml-block-placeholder"></DIV><DIV>Marie</DIV><DIV><BR class="khtml-block-placeholder"></DIV><BR><DIV><DIV>On 12 May 2006, at 18:22, Robert Oostenveld wrote:</DIV><BR class="Apple-interchange-newline"><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Dear Marie,</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">On 10 May 2006, at 16:31, Marie Smith wrote:</DIV> <BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">I have a question about the solution of a beam-former analysis and would appreciate any suggestions. Having used the beam-former technique to localize a region of interest for a specific time-frequency range, is there some function that can be implemented to compute the time course of activation for this roi?</DIV> </BLOCKQUOTE><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">For that you would use a time-domain beamformer, i.e. the lcmv beamformer (cfg.method='lcmv' in sourceanalysis). That requires time-domain data as input, so you should use timelockanalysis to compute the covariance and the average. The covariance is used to construct the beamformer filter and the average is projected through the filter. If you want to project single-trial data through the filter, you should keep the trials in timelockanalysis and use the option cfg.singletrials='yes' in sourceanalysis (see its help).</DIV></BLOCKQUOTE><BLOCKQUOTE type="cite"><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">If you are interested in a specific frequency band, you can use a band-pass filter in timelockanalysis (the options for that are hidden in the documentation, but they are the same as in preprocessing, e.g. bpfilter='yes' and bpfreq=[low high]). It could also be that you want to use a filter based on a narrow frequency band and use it to beam the broad-band data. That is also possible, but not smoothly: you have to do timelockanalysis twice (broadband and narrowband) and replace the broadband covariance with the filtered narrowband covariance. I hope this short explanation is enough.</DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; min-height: 14px; "><BR></DIV><DIV style="margin-top: 0px; margin-right: 0px; margin-bottom: 0px; margin-left: 0px; ">Robert</DIV> </BLOCKQUOTE></DIV><BR></BODY></HTML>