Table 1.

Timing of the adolescent delta power decline: Sex differences and relation to pubertal timing

Model	Delta M, y	Delta M adjustment	Adjustment significance	Between-subject M variance	Variance explained, %
Gompertz	13.08	—	—	0.84	·
Gompertz + Sex	12.53	1.21	P < 0.0001	0.57	32
Gompertz + Tannerph M	13.11	0.85	P < 0.0001	0.42	50
Gompertz + Tannerb/g M	13.04	0.62	P < 0.0001	0.51	39
Gompertz + Sex + Tannerph M	12.64	—	—	0.28	67
Sex	—	0.90	P < 0.0001	—	—
Tannerph M	—	0.71	P < 0.0001	—	—

The Gompertz equation fit to the age-related change in delta power declined most rapidly (delta M) at 13.08 y. Delta M differed significantly between sexes, with girls’ delta M at 12.53 y and boys’ delta M 1.21 y later. Delta M was also significantly related to the timing of pubertal maturation, with delta M occurring 0.85 y later for every year later in Tanner_ph M (age of most rapid Tanner stage increase) and 0.62 y later for every year later in Tanner_b/g M. The timing of the delta decline was significantly related to both sex and pubertal timing when sex and Tanner_ph M effects were evaluated simultaneously.