The programme controls how and when brain genes are expressed at different times in a person’s life to perform a range of functions, the study found.
Experts say the timing is so precise that they can tell the age of a person by looking at the genes that are expressed in a sample of brain tissue.
Scientists analysed existing data which measured gene expression in brain tissue samples from across the human lifespan – from development in the womb up to 78 years of age.
They found the timing of when different genes are expressed follows a strict pattern across the lifespan.
Most of the changes in gene expression in the brain were completed by middle-age, the study found.
The gene programme is delayed slightly in women compared with men, suggesting that the female brain ages more slowly than the male.