Fig. 2: Changes in MTL volume associated with ovarian hormones across the menstrual cycle.

a–d, Column 1: example T2-weighted image, T1-weighted image and MTL segmentation for CA1 (a), subiculum (b), perirhinal area 35 (c) and parahippocampal cortex (d). Column 2: after segmentation, unique associations between ovarian hormones and MTL regions across the menstrual cycle (Mens, menstrual; Pre-O, pre-ovulatory; Ovul, ovulation; Post-O, post-ovulatory; Mid-L, mid-luteal; Pre-M, premenstrual). Linear mixed-effects model statistics are shown (with uncertainty intervals (equal-tailed) and P values (two-tailed) computed using a Wald t-distribution approximation, and corrected for multiple comparisons using the Benjamini–Hochberg procedure at an FDR-corrected threshold of q < 0.05). The center of the error band represents the mean, with the shaded area representing +95% CI based on the bootstrap distribution for hormone levels or subregion volumes. Asterisks refer to statistically significant changes (corrected for multiple comparisons) in volume over timepoints. Details are as follows. a, CA1: Mens versus Pre-O, P = 0.001; Mens versus Post-O, P = 0.006; Pre-O versus Mid-L, P = 0.022; Pre-O versus Pre-M, P = 0.025. c, Area 35: Mens versus Mid-L, P = 0.004; Pre-O versus Mid-L, P = 0.007; Mens versus Post-O, P = 0.025. d, Parahippocampal cortex: Mens versus Mid-L, P = 0.0001; Mid-L versus Pre-M, P = 0.005; Mens versus Pre-O, P = 0.007; Mens versus Post-O, P = 0.02; Mens versus Pre-O, P = 0.042. *P < 0.05, **P < 0.005. N = 27.