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Dear SPM experts, I would like to see if there is a correlation between the BOLD signal during one condition and the performance outcome. For this I did a multiple regression, entering the contrast images of all subjects (32) under scans, and a vector of the 32 corresponding performance outcomes as a covariate. I got a number of significant clusters and wanted to display the relation between the brain activation in these clusters and the performance outcome in a scatter graph. I extracted the beta values from the peak voxels using marsbar and plotted these against my performance variable. To my surprise there was no correlation. I also tried extracting the values using rfxplot and I got similar results. My question is how it is possible that voxels that show up as significant with regression analysis do not show a correlation with the covariate? Did I do something wrong or is there something in the statistics that I do not understand? Any response would be greatly appreciated. Kind regards, Selma ________________________________ De inhoud van dit bericht is vertrouwelijk en alleen bestemd voor de geadresseerde(n). Anderen dan de geadresseerde(n) mogen geen gebruik maken van dit bericht, het niet openbaar maken of op enige wijze verspreiden of vermenigvuldigen. Het UMCG kan niet aansprakelijk gesteld worden voor een incomplete aankomst of vertraging van dit verzonden bericht. The contents of this message are confidential and only intended for the eyes of the addressee(s). Others than the addressee(s) are not allowed to use this message, to make it public or to distribute or multiply this message in any way. The UMCG cannot be held responsible for incomplete reception or delay of this transferred message.