Are Our Brains Our Own?

I can't always follow a train of thought. The way my brain physically processes thoughts is rerouted. Always has been. BUT! More recently I can feel my brain working hard to retrieve even the simplest of thoughts or memories. Is it the new drug Ive been on for about 4 weeks? A friend of mine (and a former doctor of behavioral pharmacology) has said "YoU ARE your brain!"

When I take new psych meds I sometimes can feel how they are affecting my synapses- how I feel, how my thought patterns have changed,etc.

Are our brain our own? Being bipolar I don't really think so. We just borrow them from moment to moment.