Table 3.
Lateralization indices (LIs) and hemispheric lateralization for the enrolled subjects
| Arcuate fasciculus number of streamlines (SLI) | Arcuate fasciculus fractional anisotropy (FALI) | Verb generation fMRIa (VLI) | ||||
|---|---|---|---|---|---|---|
| Right‐handed (N = 158) | Atypical (N = 82) | Right‐handed (N = 113) | Atypical (N = 53) | Right‐handed (N = 141) | Atypical (N = 73) | |
| LIs | 0.54 (0.45) | 0.52 (0.52) | 0.032 (0.027) | 0.030 (0.039) | 0.44 (0.30) | 0.35 (0.44) |
| Lateralizationa | ||||||
| Left | 128 (81.0) | 67 (81.7) | 2 (1.8) | 1 (1.9) | 125 (88.7) | 55 (75.34) |
| Symmetric | 15 (9.5) | 4 (4.9) | 111 (98.2) | 52 (98.1) | 12 (8.5) | 6 (8.22) |
| Right | 15 (9.5) | 11 (13.4) | 0 (0) | 0 (0) | 4 (2.8) | 12 (16.44) |
Lateralization indices for fractional anisotropy (FALI) were determined only for the portion of subjects, in which streamlines for the direct pathway of the arcuate fasciculus were reconstructed in both hemispheres. Also, LIs based on the verb generation fMRI task (VLI) were determined only for the portion of subjects who underwent both fMRI and DTI procedures
Note. Data are reported as mean (S.D.) for lateralization indices (LIs) and as frequency (percentages) for the distribution of lateralization (left, symmetric, and right). Lateralization indices for arcuate fasciculus (SLI and FALI) and verb generation fMRI (VLI) were determined with LI ≥ 0.1 as left‐lateralized, LI ≤ −0.1 as right‐lateralized, and −0.1 < LI < 0.1 as symmetric.
Verb generation fMRI lateralization patterns were significantly different between right‐handed subjects and atypical handedness (χ 2 = 12.92; p = 0.0016).