RE: Call for expertise: across session fMRI analyses

Hi Andre, I have done that many times at the Montreal Neurological Institute with fMRIStat (the MNI software). For example, in 1 experiment I had 6 runs per subject. So, I analyzed each run separately first specifying all the contrasts and then combined all 6 runs of each subject together at a second level of analysis. Mind you, all the conditions/contrasts appeared in all the runs. Then transformed those results into Talairach space before doing the group analysis of all the subjects (I had 15 participants). I hope this helps, Katerina **************************************************************** Dr. Ekaterini Klepousniotou Lecturer in Cognitive Neuroscience & Neuropsychology Institute of Psychological Sciences University of Leeds Leeds LS2 9JT UK Tel: +44 (0)113 3435716 Fax: +44 (0)113 3435749 -----Original Message----- From: andre(a)ynic.york.ac.uk [mailto:andre@ynic.york.ac.uk] Sent: 08 July 2008 13:46 To: ynic-users(a)ynic.york.ac.uk Subject: Call for expertise: across session fMRI analyses Dear Users, Concatenation or higher level stats? We would value the input of any users who have experience of 'combining' fMRI data across multiple runs for more robust averaging. The issue arises when trials of an experient are acquired in different data blocks due to technical limitations of scan scquisition protocols or often to reduce the strain on participants in a single session. I have searched many available resources. There are well documented routines for (1) analysinng the sessions individually and then compring them with a higher level analysis or (2) demeaning the two timeseries and combining them into a single one .. then following the standard analysis individual subject routine. Comments would be appreciated (especially from anyone has first hand experience of doing this). Thanks Andre' -- ynic-users mailing list ynic-users(a)ynic.york.ac.uk https://www.ynic.york.ac.uk/mailman/listinfo/ynic-users