Effects of sex on arousal thresholds (n = number of infants)
| Study | Active sleep | Quiet sleep | ||
|---|---|---|---|---|
| Female | Male | Female | Male | |
| 2–4 wk | 154 (14) (n = 23) | 159 (15) (n = 19) | 239 (24) (n = 23) | 233 (23) (n = 18) |
| 2–3 mth | 83 (9) (n = 22) | 99 (15) (n = 16) | 322 (41) (n = 22) | 272 (55) (n = 16) |
| 5–6 mth | 119 (19) (n = 20) | 91 (17) (n = 14) | 495 (68) (n = 18) | 538 (64) (n = 15) |