Hi,
there are a number of complicated reasons for this, all of which I will
not go into :) but one thing worth checking is the mask.img that results
when adding vs. not adding this subject. Perhaps he has no data where
otherwise all subjects do (and show a group effect), which would lead to
these voxels being masked out. Just a hunch.
Cheers,
Marko
Jen Pokorny wrote:
> Hi -
> I keep getting an error "no significant voxels" after 2nd level model
> estimation doing a 2 sample t-test (SPM 5). It only does this when I add
> a particular subject (who does have significant voxels when checked
> individually) and only happens for one condition - all other conditions
> run fine with significant results when this particular subject is added
> to the group. Any suggestions on why this error is occurring, what it
> means, and if there is a way to work around this?
> Thanks in advance!
> Jen
>
>
>
>
>
> ----------------------------------------------
> Jennifer Pokorny, Ph.D.
> Postdoctoral Fellow, Autism Research Training Program
> NeuroCognitive Developmental Lab
> Center for Mind and Brain, UC-Davis
> 202 Cousteau Place, Suite 255
> Davis, CA 95618
> (530) 747- 3808
> email: [log in to unmask] <mailto:[log in to unmask]>
--
____________________________________________________
PD Dr. med. Marko Wilke
Facharzt für Kinder- und Jugendmedizin
Leiter, Experimentelle Pädiatrische Neurobildgebung
Universitäts-Kinderklinik
Abt. III (Neuropädiatrie)
Marko Wilke, MD, PhD
Pediatrician
Head, Experimental Pediatric Neuroimaging
University Children's Hospital
Dept. III (Pediatric Neurology)
Hoppe-Seyler-Str. 1
D - 72076 Tübingen, Germany
Tel. +49 7071 29-83416
Fax +49 7071 29-5473
[log in to unmask]
http://www.medizin.uni-tuebingen.de/kinder/epn
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