It does what it says, it adds a 2nd regressor for each regressor you
have specificed. the new regressor is the 1st derivative ( in time ) of
the original regressor. This essentially can be used to absorb variance
due to relative shifts between timing of your acquisition and expected
BOLD response. There are other metrics you can calculate as well from
the use of the derivative.
If you use this type of modeling, you should probably do a proper
literature search such that when you go to publish you will be able to
properly defend your methods.
Best of luck.
-Robert
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Robert C. Welsh, PhD
Research Assistant Professor
Departments of Radiology and Psychiatry
University of Michigan
(734) - 764 - 8541 (fax)
(734) - 647 - 6781 (Ofc)
rcwelsh @ med.umich.edu
>>> Ignacio Letelier <[log in to unmask]> 11/13/2009 2:54 PM >>>
Hi.
Do anybody know what the 'Add tempoal derivative' button mean in the
General
Linear Model setup of FEAT?
Best Regards
--
Ignacio Letelier Aguirre.
Estudiante Ingeniería Civil Biomédica
Universidad de Valparaíso, Viña del Mar.
Teléfono: 97139955
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