My thoughts are quite jumbled today but your post has made me think.

I reckon there are a few things that make you borderline or and bipolar.
Some people I think are just born extremely sensitive,
then there's genetics
and then there's circumstance.

For me when I look back I think I was born that way, a lack of empathy and a dose of abuse certainly leads me to a better understanding of why I overreact in certain situations.

I recall having moods and seeing things from a really early age. My parents and teachers just expressed that I had a big imagination. Which is true I do. I'm a pretty creative person . My thoughts are usually on fire to a certain degree and I can't always get the concentration though to funnel them into some useful or spectacular.

["B]I would become isolated - conjure up creative links between all my classes - and focus all my attention on creating theories and new ways of thinking... The scary part about it is - it was [for the most part - minus the emotional parts ] intelligent and could potentially be useful in some ways..." [/B]

I do a version of this when spill into depression or mania, then my world becomes interlinked , bird's flight paths have coded meanings that only I have the key to, birds will start appearing everywhere, then they'll send messages, sometimes they will break into atoms I will see their atoms connected to mine, I am one I know the secret of invisibility etc.. Cars become colour coded they will determine the fate of the day. Actually I am seeing links that nobody will see, but I know I am right.

I was quite convincing as a child I got my friends to rescue bees with water because they were the messengers of the animal kingdom and I had a direct link to Morgan le fay who spoke to me through my lip balm and clouds in the sky. I know that all sounds a bit loopy but it made sense at the time.

I think when I was a child I just excepted all this as reality and didn't question it much. However; when I became a teenager my thoughts were still going interesting places others around me had lost the curiosity and they all began to give signals that my thinking wasn't like their thinking and I was odd.

And the more you feel odd the more your inner critic starts to chastise you and the pain in rejection becomes a trigger for the BPD, So I would feel all this stuff at the time but not know what it was I was feeling . I had to stop feeling because it was constant heartache. So in my case i drank which made the feeling happy but I would take this too far and I would get crazy upset. that pattern has been pretty much my life. Especially when it is re-enforced that any emotion is somehow wrong.

for me the bipolar aspect happened much later although now I recognise patterns in my life when I think it was more hypo mania than mania. As you said the Bipolar mood seems to be a more constant whereas the BPD will flare up like a bonfire with gasoline.

It was really when they told me I had psychotic depression and they started to medicate me with anti-depressant that I first experienced full blown manic symptoms. I have done a lot of work on my BPD and that has calmed down an awful lot but my bipolar symptom have become very difficult to manage. So actually I am really interested to know if that's happened to anyone.

I take seroquel too and it has helped with hearing and seeing stuff all the time. It also means I sleep now but I've had some things like brain fog, tiredness, weight gain.
I definitely think the BPD moments can trigger a manic or depressive episode though.