Growth hormone (GH) levels increase to high concentrations just before puberty and then progressively decline with age. GH deficiency (GHD) originating from childhood is treated with GH supplementation to increase body size (mainly height) during adolescence. To date, it is still not clear if or how early GH replacement affects memory in adulthood, or whether it can prevent the cognitive deficits commonly observed in adults with childhood onset GHD.

In a very clear and concise study, Nieves-Martinez et al. have evaluated in an animal model the question that is being debated in clinical endocrinology about the effect of GH on learning and memory. Their results indicate that GHD in adolescence deleteriously impacts brain function later in life and may result in the early emergence of age-related deficiencies in learning and memory unless prevented by GH supplementation. Nieves-Martinez et al., Journal of Endocrinology, DOI: 10.1677/JOE-09-0323