deletions | additions       diff --git a/Assumption_is_made_that_the__.md b/Assumption_is_made_that_the__.md  index 878cc2e..e183996 100644  --- a/Assumption_is_made_that_the__.md  +++ b/Assumption_is_made_that_the__.md 
...
The paper cited here adds evidence for our hypothesis that different ROIs will have different scaling factors, due to regional differences in contrast, as shown in a VBM analysis by Tardiff and colleagues. I have edited this section:    *We *"We  hypothesized that all differences in* ***regional*** *contrast and geometric distortion result in regional volumes that are consistently and linearly scaled from their true value. For a given region of interest (ROI), two mechanisms impact the final boundary definition: gradient nonlinearities cause distortion and, simultaneously, hardware (including scanner, field strength, and coils), and acquisition parameters modulate tissue contrast, adjusting the whole boundary.* ***Previously, Tardiff and colleagues have found that contrast-to-noise ratio and contrast inhomogeneity from various pulse sequences and scanner strengths cause regional biases in VBM\cite{tardif2010regional,tardif2009sensitivity}, and therefore we hypothesized that each ROI will scale differently at each site.*** *By imaging 12 subjects in 20 different scanners using varying acquisition schemes, we were able to estimate the scaling factor for each regional volume at each site...* site..."*