Spiritual Forums - New intruder :)

Hi, another new one here.
I must start by saying that I'm probably the most rational person you can imagine. But being rational can lead to beliefs that most people consider highly irrational. For example, I ask myself "why do I think?".
Is it because tiny electric currents flow through my brain or do these currents flow through my brain because I think? If the first were true, there would be no free will, no responsibility, no "me". Everything I think would be the result of electrical currents in my brain, influenced by input of my nervous system which would be triggered from the outside by light, sound, touch, smell etc. Even if I'd question my existience it would still be the result of some physical or chemical event in my body that changes those tiny currents in my brain. Of course this could still be the truth, but it would make actively contemplating things an irrational action, because everything I come up with would happen anyway.
If a thought is either true or not and I can't determine which it is, I have to believe what makes more sense to me.
So in my case the rational conclusion is that my "mind" or "soul" or "me" is not the sole result of my body's activity but either the cause or at least a partner.
That leads to a lot of further questions like "where is the mind located", "does it depend on the body", "how did the two get connected" and soon the most rational person is waistdeep in spiritual thoughts and beliefs.
I'm looking forward for an exchange of ideas in this forum that may help me find myself in the long run.
Marcel