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Dear David,
   
  Thank you very much! By the way, what do you think about the efficiency of ICA? Does spatial-ICA have the ability 
  to seprate the genine BOLD signal from the false signal induced by task-related movements?
   
  Zhiqiang Zhang
  

David Carmichael <[log in to unmask]> д
                Dear Zhang,
   
  You should use realignment parameters and possibly scan nulling as extra regressors in your GLM which will remove false positives from your results. If movement always occurs with your task then you cannot separate the motion form the response and you need new data! 
   
  See 
  Lemieux L, Salek-Haddadi A, Lund TE, Laufs H, Carmichael D. Modelling large motion events in fMRI studies of patients with epilepsy.Magn Reson Imaging. 2007 Jul;25(6):894-901.
   
  And 
  K.J. Friston, S. Williams, R. Howard, R.S.J. Frackowiack and R. Turner, Movement-related effects in fMRI time-series, Magn Reson Med 35 (1996), pp. 346C355.
   
  Regards
  David
   
  ______________________________________
   
  David Carmichael PhD MInstP
  Senior Research Fellow in MR Physics
  Department of Clinical and Experimental Epilepsy
  Institute of Neurology, University College London
   
  Correspondence to:
  Wellcome High Field MR Research Laboratory
  University College London
  12 Queen Square
  London WC1N 3AR
   
  Tel +44 (0)20 76762006
  Fax +44 (0)20 76762005
  email [log in to unmask]
   
   
   
  -----Original Message-----
From: SPM (Statistical Parametric Mapping) [mailto:[log in to unmask]] On Behalf Of Zhang Zhiqiang
Sent: 22 April 2008 08:56
To: [log in to unmask]
Subject: [SPM] How to eliminate the head movement related to task?
   
    Dear SPMers,

     

    I have a special case whose fMRI data is found having task-related movements during scan. the maximal extent is 2.5mm. I'd like to know how to eliminate the false effect to result of this movement ? is there any paper focusing on this? 

     

    Thank you very much!

     

    Zhiqiang Zhang, 

    
    
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