TABLE 4:

Temporal lobe gray and white matter ratios

GroupGray MatterWhite Matter
TICV Ratio*TBV RatioTICV Ratio*TBV Ratio
Autism (n = 26)13.98 (7.96)15.22 (8.61)7.66 (4.40)8.35 (4.81)
Autism with macrocephaly (n = 12)15.70 (7.54)16.84 (8.07)9.19 (4.51)9.86 (4.88)
Control (n = 19)17.36 (4.43)18.67 (4.67)9.92 (2.65)10.68 (2.86)
Benign macrocephaly (n = 8)13.46 (8.56)14.77 (9.38)8.42 (5.78)9.23 (6.30)
Reading disorder (n = 17)15.13 (7.29)16.24 (7.83)9.05 (4.42)9.70 (4.73)
F statistic0.760.670.860.75
P value.56.62.49.56
  • Note.—Data are the mean. Numbers in parentheses are SD.

  • * TICV Ratio = (Temporal Gray or White Matter/Total Intracranial Volume) × 100

  • TBV Ratio = (Temporal Gray or White Matter/Total Brain Volume) × 100