Fig. 5

Within Group Comparisons of Sulcal vs Gyral GFAP. Within group comparisons of sulcal versus gyral GFAP were calculated using a relative ratio of sulcal:gyral GFAP. The Blast-RHI CTE group had higher GFAP at the sulcus relative to the gyrus in terms of percent positivity at the subpial surface (A), while the RHI-CTE group had higher GFAP at the sulcus relative to the gyrus at the subpial surface in both percent positivity and mean intensity (A, B). Within the cortex, the Blast-RHI group had significantly higher GFAP in the sulcus in terms of percent positivity (B), while the RHI and RHI CTE groups had significantly greater sulcal predominance in terms of both percent positivity (B) and mean fluorescent intensity (E). At the GWMI (C, F), all groups except RHI had significantly higher GFAP intensity at the sulcus relative to the gyrus (F). The RHI CTE group had significantly less at the sulcus in terms of percent positivity (C). Ratio data were log transformed and analyzed using one-way t-tests. Values significantly greater than zero indicated higher GFAP at the sulcus (sulcal predominance), while values significantly lower than zero indicated higher GFAP at the gyrus (gyral predominance). Error bars represent standard error of the mean. *P < 0.05, **P < 0.01, ***P < 0.001