Hi Group-ICA is carried out in grayordinate space. Then:
For each subject, subject-wise grayordinate AND volumetric maps (versions of the group-ICA) are estimated using dual-regression, with node-timeseries normalisation, and outputs in units of GLM betas (parameter estimates) not Z. These volumetric maps are then averaged across subjects to generate the group-average volumetric maps distributed from HCP. So how you threshold these is up to you and depends what the intended usage for that is....... Cheers. > On 6 Jul 2016, at 07:26, Nicola Toschi <[email protected]> wrote: > > Hi, > > The volumetric version! > > Thanks in advance, > > Nicola > > > -------- Original message -------- > From: Stephen Smith <[email protected]> > Date: 04/07/2016 12:37 PM (GMT+01:00) > To: Nicola Toschi <[email protected]> > Cc: hcp-users <[email protected]> > Subject: Re: [HCP-Users] Exact Meaning of ICA maps in 800 subjects release > > HI - do you mean the grayordinate or volumetric versions? > Cheers > > > >> On 4 Jul 2016, at 11:16, Nicola Toschi <[email protected] >> <mailto:[email protected]>> wrote: >> >> Hi list, >> >> This may be more of a MELODIC question, but I would be grateful for any >> input: >> >> In the ICA release on 800+ subjects, what is the exact mathematical meaning >> / definition of the (non-binary) intensities of the different component >> volumes? >> >> Are they easily relatable to a statistical map (I am looking to threshold >> them to study main clusters and possibly correct for multiple comparisons)? >> >> Thanks in advance, >> >> Nicola >> >> _______________________________________________ >> HCP-Users mailing list >> [email protected] <mailto:[email protected]> >> http://lists.humanconnectome.org/mailman/listinfo/hcp-users >> > > > --------------------------------------------------------------------------- > Stephen M. Smith, Professor of Biomedical Engineering > Head of Analysis, Oxford University FMRIB Centre > > FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK > +44 (0) 1865 222726 (fax 222717) > [email protected] <mailto:[email protected]> > http://www.fmrib.ox.ac.uk/~steve <http://www.fmrib.ox.ac.uk/~steve> > --------------------------------------------------------------------------- > > Stop the cultural destruction of Tibet <http://smithinks.net/> > > > > > > _______________________________________________ > HCP-Users mailing list > [email protected] > http://lists.humanconnectome.org/mailman/listinfo/hcp-users > --------------------------------------------------------------------------- Stephen M. Smith, Professor of Biomedical Engineering Head of Analysis, Oxford University FMRIB Centre FMRIB, JR Hospital, Headington, Oxford OX3 9DU, UK +44 (0) 1865 222726 (fax 222717) [email protected] http://www.fmrib.ox.ac.uk/~steve <http://www.fmrib.ox.ac.uk/~steve> --------------------------------------------------------------------------- Stop the cultural destruction of Tibet <http://smithinks.net/> _______________________________________________ HCP-Users mailing list [email protected] http://lists.humanconnectome.org/mailman/listinfo/hcp-users
