Class Reunion - Class of 1969 - Liberty, Mississippi
But not our brains. Every cell in there is irreplaceable. By and large, we cannot grow new brain cells, a fact that every neuroscientist is drilled on as a student. It was recently discovered that some neurons continue to grow in the adult brain, through a process called neurogenesis—but the majority of brain cells stay with us for a lifetime, rendering them particularly susceptible to the wear and tear that naturally occurs with time. This is partly why diseases like Alzheimer’s are so devastating since they destroy neurons that to our knowledge are irreplaceable.