Dear SPM users,
I am having a doubt regarding the High pass
filter. Kindly clarify the same.
I am using SPM2. The default high-pass filter is
128 seconds i.e 0.008 Hz. The regressors frequencies
in my experiment is 0.004Hz. So, if I process
with the default value,the main (high)peaks of all my
regressors are filtered out- while seeing
the "frequency domain" graph of the spectral density.
Now,I am having confusion whether should I
change
the cut-off frequency value during data specification
with 480second (0.002Hz)based on SPM 99
recommendation i.e., two times the longest interval
between two appearances of the most frequently
occurring event.or just I can resume my
processing with the default value.
Kindly show some light
Suthi
PhD student
____________________________________________________________________________________
Be a better friend, newshound, and
know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ
|