Fig. 2.

Average hemispheric LIs (left) and group activation (right) for letter-word generation task in the control, tumor, and vascular lesion patient groups. Left: the average LIs for tumor patients (n = 42), vascular lesion patients (n = 10), and controls (n = 25), from the letter-word generation task, are shown at different threshold values for the hemispheric mask. Tumor patients show bilateral dominance regardless of t-value. Tumor patient LIs are significantly different from control LIs at each threshold (ps < 0.0125, Table 5). Vascular lesion patients show bilateral dominance at t < 2.0 and left lateralization at t < 4.0. Vascular lesion patient LIs are significantly different from control LIs at at t < 2.0 (p < 0.0125, Table 5). The control group maintains left lateralization despite variable threshold effects. Right: images display the group activation maps at low threshold values (ts < 2.0) and at higher threshold values (ts < 4.0). The control subjects (A) show average left language lateralization, the vascular lesion patients (B) show average bilateral and left-lateral dominance, and the tumor patients (C) show average bilateral dominance during the letter word generation task.