Daniel, I find the brain activity comparisons to be very interesting. I never have given it much thought that it could be that different. Wow, it certainly looks different!
I totally understand the concept of 'being led' - sometime it is very heavy on my heart to say or do something for others and other times, it isn't. I try to listen to my heart and act when I feel led and not necessarily act when I don't. I've always imagined it was the Holy Spirit putting it on me. Having been raised AG from a young age, I'm very familiar with others speaking in tongues, but as hard as I tried, it hasn't been a gift I've been blessed with. Although I too have felt God's presence at times when someone else was speaking, and haven't felt His presence at others. Last May while in Scotland with my aunt (who hasn't spoken to me in months - she is very condeming of my sexuality and relationship), who speaks in tongues although I don't necessarly feel the Lord's presence - anyway, she spoke to a group of Charismatic Catholics. They had a tongue speaking session where it appeared I was the only one not participating, and then the deal where she touched them and they fell. I was a little taken back at how disorganized it all felt, and did not feel the presence of God, but did feel like I wanted to leave. It was very strange for me, although I'm not in a position to say it wasn't God's work. My aunt told me once, she could pray with me and I could speak in tongues, I just have to start babbling baby talk and then it would come. Thought that was strange also. I don't believe we are all entitled to all gifts of the Spirit.
"Struggle is a never ending process. Freedom is never really won, you earn it and win it in every generation."
Coretta Scott King