[Homer-users] time scale of HOMER2 Data window

[Borbala Kollod]

Hello All!

I have some clarification questions about the the scales of the Data window and the mechanism of HRF block averaging.
For the scale I guessed  the 'y' axis in concentration view would refer to mikroMols of conc. chaneges. The 'x' axis would refer to time in seconds.
But then I have this strange result for a channel (attached jpeg) that in one subject's data I averaged 3 trials of the 'blue' condition, and in the HRF I got a huge dip of concentration around 14s after stim onset. Checking the Time course view this huge dip is present after the 3rd trial, but not at 14s after stim onset but later, around 22s. If I exclude the 3rd trial, the dip disappears from the HRF.
I used the default precessing stream (also attached). Also the datafile is attached, the above mentioned channel is the one between detector3 and sourceB.


Can anybody give a cue of that difference in time course view and HRF view?
Checking the data with another program it seems that the time course view is correct and the tricky part is the HRF view.

Thanks,
Bori Kollod




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