Woolf, Narrative, and Perspective

What struck me most about To the Lighthouse was obviously the odd narrative style, specifically, the manner in which the narrative seems to switch perspectives in different ways. There are clearly times in which Wolfe uses chapter demarkations to represent the same event through multiple perspectives. The most obvious example of this is Chapter XV which seems to be entirely dedicated to Prue answering a question. However, Wolfe's narrative also seems to switch focus within chapters too. At times it seems similar to free, indirect discourse; yet the use of paratheticals really trips me up. The parentheticals occur mostly when the character which the narrative is focused seems to imagine another character's thoughts. However, the origin of these parentheticals is not at all clear. If this is intended as a stream of consciousness, then it is odd that it would be represented in paratheses which presumably are absent from a charachter's train of thought. This leads me to wonder whether these words in the parenthesis are intended to be the charachter's thoughts, the narrator's thoughts, or the the thoughts of the charachter being imagined? All of these potential solutions are problematized by specific instances within the text, and it is the lack of consistency that really tripped me up.