It's quite hard to change personality because it's so static, but if you really set your mind to it, you probably could.
I used to be a pretty shy kid in middle school who was terrified with talking to people, but I got really tired of it. There are huge disadvantages to being so closed off. So, I set my mind to it and tried to change myself in high school, and now, I'm really extroverted and confident, but not that annoying jock type who makes inappropriate jokes. More like that approachable, confident type of person who gets enthusiastic a lot of times.
The key to adapting to a type of personality that you want is to step out of your comfort zone. Try doing things you normally wouldn't do. My "stepping out of my comfort zone" was talking to people and start contributing to conversations and just sucking up the "What if saying Hi to strangers turns out awkward?" mindset and just said hi to people. It was awkward a few times at first, but I got a lot better at it once I started doing it a couple more times.
There is no one "MD personality". Just find one that suits you and try stepping out of your comfort zone.