Yes. All personality traits, including confidence, live in the brain. The brain is made up of specialized cells called neurons. These neurons communicate with each other via synapses (the connection between neurons). New synaptic connections are constantly being formed. Also, old synaptic connections are constantly being adjusted. Every time we learn or experience something, the experience, and choices we make help shape us. Sometimes what we learned becomes reinforced, and it becomes “hard coded” as part of who we are. Other times we may experience it and forget it. All of these things are happening in our brains at a cellular level. If we make a decision to be more confident and we practice it, we are reinforcing the learning. The more someone practices anything, the better we become and the more likely it is to become second nature.