I can think of a definition for “bi-polar” that has some relation to some of the articles on TWOC. Barring physical brain impairments (if this is possible, or if there can be said to be such a thing) it might be that a “bi-polar” type thinking, where someone is seemingly jumping from extremes, is really a product of having a different core view or belief.
Coming from a different view or having a different frame of reference, could create a type of tangential thinking that, viewed from a socially “normally” observer, might seem illogical or “extreme” (polar!).
Its really just a note that sometimes jumping from extremes could be logical from the bi-polar persons view. The cause then could be either mental or physical/chemical in regard to the brain and the solutions proposed.