There is much to be said about the memorability of slow motion footage in movies. While perhaps the most extreme recent example was the invention of “bullet time” in Matrix, and recently we have seen it taken to the extremes in Inception, the overcranking (shooting at higher framerate to later play it back at regular 24 fps) was the hallmark of cinematography ever since it was invented in 1904 by Austrian priest and physcist August Musger.
There is little doubt that slow motion footage for some reason does make the action seem more pronounced, more memorable, more impressive, and often more majestic. Even though some cinematographers of note did tackle the reasons why slow motion has this certain effect, so far I have not found a convincing explanation in this field.
A possible insight into why slow motion might have this effect comes from the research on how people react under extreme stress: in combat, in sports, or in situations where one’s life is threatened. There exists a number of reactions that can happen to people in such situations. Alongside tunnel vision, selective deafness, there also is a perception of events occuring in slow motion. Most likely it is a result of the sudden flush of hormones like epinephrine, and the attempts of our brains to encode as much of what is happening as possible for future reference. Usually it is accompanied by the feeling of vividness, and awareness of being alive (this is also why such states of mind can become addictive, and life can seem pretty bland afterwards), sometimes referred to as “hyper-reality”.
The important part is that the real slow motion effect in our brain is only an illusion, and the result of physiological processes of hastened memory creation. It does not grant the subject powers of Neo to dodge bullets, it only increases the awareness of occuring events. The reaction time remains as it is, even though the employed actions might be more efficient, than they would be in “normal time”.
However, it is highly probable, that our brain, when confronted with slow motion footage, takes it as a signal of something memorable happening, and tries to employ its standard procedure in such cases – trying to remember as much as it can, because it is an important, potentially life-threatening event. Due to the fact, that there is no hormonal rush, the effect is subsided, but it seems to have an impact nevertheless. How foolish of our brain to think so! And yet, we fall for the same trick again, and again. And slow-motion does work, even if used in excess.
Therefore, next time you see the slow motion footage employed to accentuate certain aspects of the action, or use this effect yourself, be aware that it works, because it references the state of mind that is already available to the viewer, and mimics what happens when our brains do firecely try to create a memorable event.
If readers are interested in further exploration of this topic, I suggest the book “On Combat” by Lt. Col. Dave Grossman, which has a great compilation of physiological effects that accompany events.