At the time of birth, a baby’s brain has roughly 100 billion neurons, but it began with nearly twice as many as an embryo. Starting in the third trimester, the brain eliminates unnecessary neurons via a process known as apoptosis. – WTF Fun Facts
Source: https://sites.duke.edu/apep/module-5-alcohol-and-babies/explore-more/normal-brain-development/
What interesting information! i wonder if that process may sometimes lead to little accidents where some neurological conditions may arise – such as learning difficulties, ADHD, autisim spectrum disorder, or propensity for bad mental health, after nature’s overzealous ‘shedding’ (for want of a better word) of neurons – & if genetics might play a part in the process.