Researchers discovered that, contrary to previous assumptions, an adult human brain is still capable of creating nerve cells.
For years, scientists believed that the adult human brain no longer produces new brain cells. However, a recent study conducted by researchers from the Columbia University revealed that aging brains still create as many new nerve cells as young brains do.
The paper which was published in the journal Cell Stem Cell contradicts an earlier study which suggested that brain cell production stops in childhood.
“When I went to medical school, they used to teach us that the brain stops making new cells,” Dr. Maura Boldirini, a neurobiologist from Columbia University and lead author of the study, said.
Dr. Boldirini and her team studied hippocampi from the autopsied brains of 28 people with ages ranging between 14 and 79. For their research, the neuroscientists used donors that have no history of psychiatric illness or chronic illness–a far cry from studies conducted in previous years.
Aside from that, the brains were also free of controlled substances.
Instead of just a portion, the researchers studied the whole hippocampi, or the part of the brain which is believed to be the center of emotion, memory, and the autonomic nervous system.
This allowed Dr. Boldirini and the other researchers to make more accurate estimates of the number of neurons present in the brains.
During their experiment, the researchers searched for certain proteins that are being produced by brain neurons at specific stages of development. These proteins include GFAD and SOX2, which are both abundantly produced by stem cells, eventually turning into neurons.
Their findings suggest that the hippocampus’ size remains the same while new cells produced by the brain continue to grow throughout a person’s life.
“We found that older people have similar ability to make thousands of hippocampal new neurons from progenitor cells as younger people do,” Dr. Boldirini was quoted as saying. “Nevertheless, older individuals had less vascularization and maybe less ability of new neurons to make connections.”
While the study indicated that the number of neural stem cells in adult human brains are not as many as those in younger brains, there’s evidence that aging brain still had thousands of the neural stem cells.
Also, the researchers observed that older brains have less new blood cell formation and protein markers which enable the brain to make new connections between the neurons.