I'm not sure if this is relevant, but I've noticed that applying high
pass temporal filtering to EVs sometimes produces strange dips at the
beginning in the resulting design matrix columns...could high pass
filtering do this to the initial timepoints of the functional data?
Dan
On 7/31/07, Vishwadeep Ahluwalia <[log in to unmask]> wrote:
> Hi,
> I plotted the mean time series extracted from filtered_func image within
> different ROIs and found that the first two values of each time series is
> way less than the consequent values. I'm assuming this is done on purpose
> and is not an artifact. Can anyone tell me why this is done and what
> pre-processing step causes this decrease? Thanks!
> -Vish
>
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