Stanford Researchers Propose Brain Consists of Two Distinct Organs
A study by Stanford University suggests the human brain may be composed of two independently evolved organs, a finding that could aid research into brainstem disorders such as ALS and spinal muscular atrophy.
Scientists at Stanford University have presented evidence that the brain may be formed from two separate organs that developed independently over hundreds of millions of years. The research, published in Nature Neuroscience, indicates that the hindbrain follows a developmental pathway distinct from that of the forebrain and midbrain, a pattern also observed in jellyfish.
The study, which examined mouse embryos, found that the hindbrain—responsible for vital functions such as breathing and heart rate—originates from different progenitor cells than the forebrain, which governs higher-order processes like language and consciousness. > "We’ve shown for the first time that the front of the brain arises from a totally different progenitor cell than the back of the brain," said Dr. Kyle Loh, associate professor of developmental biology and senior author of the paper. > "Our research suggests that evolution took two existing neural systems and pushed them together spatially."
According to the researchers, recognizing the brain as two distinct systems could explain challenges in culturing certain neuronal types and may improve experimental models for conditions that affect the brainstem, including spinal muscular atrophy and amyotrophic lateral sclerosis. The findings also open the possibility of growing hindbrain neurons in vitro for functional studies.
Graduate student Rayyan Jokhai, a co-first author, noted the surprise in discovering that the brain’s structure reflects an ancient dual-system organization that now operates as a single unit.