Okay kiddo, so Dick Swaab is a very smart man who studies the brain. The brain is what helps us think and feel things like happy, sad, or scared.
Dr. Swaab studied how the brain works by looking at lots of different brains from people who had died. He found out that there are different parts of the brain that do different things, like the part that controls our movements, another that helps us see and hear things, and one that helps us remember things.
He also looked at how the brain changes when people get older or when they have problems like Alzheimer's disease. He even found that some things can change our brains, like when we learn new things or when we exercise.
So basically, Dick Swaab is a very important person who helps us understand how our brains work and how we can keep them healthy.