Plain ol' ordinary flashbacks are used pretty sparingly, and for good reason--they're boring. If we're aware that something happened in the past, it automatically has a kind of who cares? feel to us. The SBF is a more interesting kind of flashback though, because the character becomes aware of the importance of the flashback at the same time as the reader--and that awareness, in turn, affects the character's actions in the front story. Sorry if that came across as complicated--I've got an example to help.
It's the novel, Someday This Pain Will Be Useful to You, by Peter Cameron. An SBF is woven through the first half of this book, in the form of a painful memory recounted by 1st-person narrator, James Sveck.
James is a witty, articulate high school senior and savvy Manhattan-ite, but he turns into a massive tangle of social anxiety around people his own age. He feels different in some fundamental way, which he says became clear to him during the "The American Classroom" (AC)--a corny school government project that takes him to Washington, DC, along with teenagers from all over the US.
The front story (the real-time action) takes place in the summer following the AC and follows James' attempts to withdraw from the world--he announces to his parents that he will not be attending Brown in the fall like he'd planned; he looks into running away and buying a cheap house in the Midwest instead; and he schemes to get the attention of the only person he regards as his "friend"--a sophisticated gay man named John who manages James' mother's art gallery. Alarmed by James' increasingly erratic behavior, James' parents insist that he talk to a psychiatrist, Dr. Adler, and it's through those office visits that James relives his "horrible experience" at the AC, generally via flashback.
I won't ruin all the delicious details of the "horrible experience" for those who want to read it, but little by little, the flashbacks tell the full story of a mental breakdown. Through this telling, the reader becomes aware of why James aggressively withdraws from everyone in the front story--and the effect makes it feel like James is becoming more aware, too, even if it takes him a while to admit it. In fact, it's the final telling of the breakdown to Dr. Adler that crystallizes James' crisis, both for himself and for the reader. In it, he recalls how he ended up at the National Gallery, staring at a series of paintings portraying the four stages of life in the form of a male figure sailing on a boat: for example, the male figure transforms from a youth sailing smoothly along, to a man facing raging waves, to an old man about to sail off the painting into a quiet, dark sea, accompanied by an angel. James explains that he was upset by these images because:
|It's a real painting! Old Age by Thomas Cole, 1842|
"... I realized I wanted to be in the last painting, Old Age. I wanted to be in the boat floating into the darkness. I wanted to skip the Manhood boat. The man in that boat looked terrified, and I couldn't understand what the point was: why crash through those treacherous rapids along a river that only flowed into darkness, death? I wanted to be in the boat with the old man, with all the danger behind, with the angel near me, guiding me toward death. I wanted to die."This moment reveals James' greatest fear--of declaring his manhood and moving forward. The effect of this revelation is to catapult both the reader and James into the major confrontation of the front story--James' hidden feelings for John, his mother's gallery manager. Right after James delivers the final scene of his breakdown to Dr. Adler, he makes a romantically confused advance on John and is forced to put all his cards out on the table--including his sexuality. This leads to the final dramatic crisis in which James changes and grows into the next stage of life that he was so afraid of.
The SBF is a really interesting way to advance storytelling--it has a unique tension that comes from the feeling that you, the reader, are "catching up" with the past and its significance to the present at exactly the same time as the main character. Plus, the "catching up" in itself becomes a sort of "springboard"--one that touches off a turning point for the main character and offers a new direction. The overall experience feels a lot more like real life, and that in itself can make a reader stay tuned in.