Your brain is uniquely yours. Even if you are an identical twin, your brain is not a replica of your twin’s.
How can that be?
Well, the makeup of your brain is determined by your DNA, but it’s also determined by your life’s experiences.
Your relationships, skills, careers, and hobbies all contribute to the shaping of your brain. Take, for example, one study of London taxi and bus drivers. This study used MRIs of the participants’ brains and cognitive, memory, and affective tests to assess their cognition. Researchers found MRI differences in the hippocampi of each group. Both groups also had significant scoring differences on their assessments.
The hippocampus is the area of the brain associated with spatial memory. This type of memory records information about your environment and how you are oriented within it. Your hippocampus helps you remember where items are located so you can navigate your body around them.
The study of these drivers indicates that their careers, which demand constant access to spatial representation, have shaped their brain. In both the bus and taxi drivers, the hippocampus shaped to most benefit to the skill required. While taxi drivers and bus drivers both have a command of navigating the city, the way they access the spatial information in their surroundings vary greatly. And so do their brains!
Close your eyes for a second and think about your hippocampus. What do you think its skills are? If you're a nurse, your hippocampus might be adept at navigating the operating room. Teachers can steer a group of children through winding hallways and complex math problems. Parents of young children seem to have very busy hippocampi, as they are constantly locating their kids' sippy cups, baseball jerseys, and favorite stuffed animals.
Whoever you are, you've done something specialized in your life that makes your hippocampus unique to you.