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Chen                                                                                                                          Comments on the composite intranetwork and internetwork connections

           that  AD pathology  may manifest focally in certain   Conflict of interest
           region of interest (ROI) pairs but not others. This is all   There are no conflicts of interest.
           good news for understanding AD pathophysiology and
           reinforces an integrative view of the brain’s functional   Patient consent
           organization.                                      No patient involved.

           After  reading the article with interest, I  have some   Ethics approval
           concerns about the study as follows:               This article does not contain any studies with human
                                                              participants or animals.
           First, in their study,  the authors defined 36 spherical
                            [1]
           (6 mm radius) ROIs by maximizing  the topographic
           concordance between mapping derived by seed-based   REFERENCES
           correlation  and by spatial  independent  component
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                                                                 ME, Holtzman DM, Morris JC, Ances BM. Loss of intranetwork and
           they separate brain areas into subnetworks that show   internetwork  resting  state  functional  connections  with Alzheimer’s
           higher interconnectivity with each other. In addition, this   disease progression. J Neurosci 2012;32:8890-9.
           approach  can lead to overlapping  anatomical  areas   2.   Chai XJ, Castanon AN, Ongur D, Whitfield-Gabrieli S. Anticorrelations
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           Second,  the  authors  emphasized  the  notion  that   3.   Deco  G,  Jirsa  V,  McIntosh AR,  Sporns  O,  Kotter  R.  Key  role  of
           composite scores can capture the critical phenomenology.   coupling, delay, and noise in resting brain fluctuations. Proc Natl Acad
           They  performed  global  signal  regression  during   Sci U S A 2009;106:10302-7.
           preprocessing to reduce non-neuronal physiological   4.   Cole DM, Beckmann CF, Long CJ, Matthews PM, Durcan MJ, Beaver
           noise  in  the  fMRI  BOLD  time  series  (Raichle  et  al. ;   JD.  Nicotine  replacement  in  abstinent  smokers  improves  cognitive
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           been  treated  as  neuronal  signals  in  the  composite   Reliable  intrinsic  connectivity  networks:  test-retest  evaluation  using
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           negative correlations can occur. Therefore, care must   Shulman GL. A default mode of brain function. Proc Natl Acad Sci U
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                                                                 H,  Reiss  AL,  Greicius  MD.  Dissociable  intrinsic  connectivity
           Third, the authors performed  a one-way  analysis     networks for salience processing and executive control. J Neurosci
           of variance  and  post  hoc  t-tests.  However, they did   2007;27:2349-56.
           not control the effects  of age, education, or sex on   8.   Dosenbach  NU,  Fair  DA,  Miezin  FM,  Cohen  AL,  Wenger  KK,
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           Nil.                                                  globally connected regions. Neuroimage 2010;49:3132-48.























            248                                                                     Neuroimmunology and Neuroinflammation ¦ Volume 3 ¦ October 28, 2016
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