The mind does seem to be produced by brain activity but we know very little of its nature. The brain, as a physical system, can be studied like any other system.
But by what mechanism do brain and mind interact?
Such interaction is two-way. Brain activity leads to changes in the mind and vice-versa. Thus, thoughts ARE able to influence material particles, and material particles ARE able to influence thoughts.
When thoughts cause changes in the brain, the brain in turn can order the body to move. And with our bodies we can accomplish a myriad tasks.
Conversely, the environment can cause changes in our bodies and these are conveyed to the brain thereby causing thoughts.
Subjectively, we can feel ourselves thinking, but how does the brain produce thought?
Is mind merely a by-product of brain activity?
If so, how is it that thought can influence brain activity?
Sit down and start thinking about what you'll do tomorrow. Somehow your thoughts can force your brain into this activity.
So what comes first, mind or brain activity? The chicken or the egg?
As we build ever-more-complex computers, might it be that their electrical activity is already giving rise to a mind?