I would like to enter a regressor that represents the neuronal activity (acquired with electrophysiology), therefore. a hemodynamic response function should be fitted to it.
It is a time series with the same duration as the fMRI scan consisting of continuous values.
I can’t find a way to do it in 3dDeconvolve: -stim_times is expecting onset times in seconds. -stim_file would accept a time series, but does not get convolved with the response model, and neither does -ortvec.
So is it the best option to manually convolve my regressor in matlab and then enter it as -stim_file? That’s ok, but I would have liked to use one of the variable shape models in 3dDeconvolve.
Not quite sure exactly what you’re looking for. Suppose that the neuronal activity at 3 consecutive time points are a1, a2, and a3. Do you want to obtain a regressor as the summation of three consecutive HRFs with each modulated by a1, a2, and a3?
Yes, basically I want the HRF, which was fitted to the data not from a stimulus time series (zeros and ones) but from the neuronal signal that has some continuous value at every time point.
-stim_times_AM2 might be exactly what I want, if I define every single time point as stimulus event which is amplitude modulated by the neuronal signal. Will try…
The
National Institute of Mental Health (NIMH) is part of the National Institutes of
Health (NIH), a component of the U.S. Department of Health and Human
Services.