A Stanford Medicine-led study found that the human brain develops from two independently originating nervous systems rather than a single developmental source.
While the forebrain and midbrain arise from one progenitor population, the hindbrain responsible for vital functions such as breathing, heartbeat and swallowing follows a separate developmental pathway. The discovery also enabled researchers to grow functional human hindbrain motor neurons in the lab, potentially opening new avenues for studying conditions including ALS and SMA.