Scientists discovered that the brain keeps making new neurons even in adulthood, offering hope for brain health treatments.

Now, researchers at Sweden’s Karolinska Institutet say they’ve found the clearest answer yet. They report the discovery of dividing neural progenitor cells — essentially the precursors to new neurons — in the brains of humans ranging in age from infancy to 78 years old.

In the hippocampus, a critical brain region for learning and memory, new cells emerge in some people into late adulthood, according to a study published July 3 in the journal Science. The findings tip the scales in a still-active debate over how our brains continue to develop throughout life.