Medial prefrontal cortex deficits correlate with unrefreshing sleep in patients with CFS

[Woolie]

As others have implied though, this sort of result is vulnerable to poor statistics, and someone with lots more clue would need to go through it in detail to work out if it's at all real.

That would be me, I think. I'm in the same line of work.

Stats-wise, the main analyses are done appropriately. They have applied familywise error correction, which is appropriately conservative for this kind of analysis (which involves huge numbers of comparisons). The only thing they've done stats-wise which is somewhat frowned upon is to perform correlation/regressions on the combined CFS and control groups in some analyses. These methods are only appropriate if you have selected participants from a continuous sample, but here the pool of participants is clearly drawn from two qualitatively different samples. But its fairly easy just to disregard these, because the main findings are in the direct group comparisons and in the correlation/regressions involving the CFS group only.

Its a pretty low resolution magnet they used (1.5T), given the purpose of the study. We use similar in our lab, but we track really huge abnormalities, so its perhaps less of a problem for us than it is for them. But I'm honestly not that worried about the resolution thing.

They used VBM, which is an automated method for detecting the broad characteristics of brain tissue. Its widely used in the area.

The only significant differences in white matter volume between patients and groups were found in the IFOFs (a bundle of white matter fibres than runs along the base of each cerebral hemisphere). And those group differences are tiny - minute decrements in white matter volume in very circumscribed areas. There were no differnes in grey matter volume.

The IFOFs come up from time to time in these types of comparisons, and it could be because they represent one of the longest bundles of white matter fibres in the brain - so therefore possibly the most vulnerable to loss.

There were also findings in this study for the insula and right internal capsule, but I would disregard those as they weren't internally coherent (differences within but not between groups).

That leaves the mPFC findings. They found reduced grey matter intensities - not volume. So a pretty small finding. Still, if replicated, it might actually prove important. Also, even if the effect turns out to be robust, we're can't say whether this is a cause of poor sleep, or a consequence of it.