Dynamic endocrine modulation of the nervous system

The brain is an endocrine organ whose day-to-day function is shaped by the rhythmic production of neuromodulatory hormones. Yet, traditional cross-subject approaches to studying brain–hormone relationships often miss a central feature of the mammalian endocrine system: hormone production ebbs and flows over time. This talk will highlight emerging evidence of sex hormones’ potent influence on structural and functional properties of the human brain. These discoveries were made possible by closely monitoring single individuals across endocrine transitions, including the circadian cycle, menstrual cycle, and pregnancy. For example, in a recent precision imaging study of pregnancy sweeping changes in white matter microstructure, grey matter volume and cortical thickness were evident week-by-week across gestation, demonstrating the brain’s capacity for extensive neural remodeling well into adulthood. Together, these findings suggest that neuroendocrine factors rapidly and dynamically influence the mammalian brain. Precision imaging designs offer scientists the unique ability to probe these dynamic interactions for the first time.