Tuesday, March 02, 2010

Hollywood Pink Noise

In a March 2, New York Times article, titled Bringing New Understanding to the Director's Cut, Natalie Angier reports the findings of a new study published in Psychological Science, titled: Attention and the Evolution of Hollywood Film (by James E. Cutting, Jordan E. DeLong, and Christine E. Nothelfer of Cornell University and the University of California, Berkeley). The study produces new evidence that "films have evolved to resemble the natural rhythms of the brain."

I found Ms. Angier's report interesting, so I decided to seek out and read the original study myself.

From the paper's abstract:

"Reaction times exhibit a spectral patterning known as 1/f, and these patterns can be thought of as reflecting time-varying changes in attention. We investigated the shot structure of Hollywood films to determine if these same patterns are found. We parsed 150 films with release dates from 1935 to 2005 into their sequences of shots and then analyzed the pattern of shot lengths in each film. Autoregressive and power analyses showed that, across that span of 70 years, shots became increasingly more correlated in length with their neighbors and created power spectra approaching 1/f. We suggest, as have others, that 1/f patterns reflect world structure and mental process. Moreover, a 1/f temporal shot structure may help harness observers’ attention to the narrative of a film."

In other words, modern films appear to share a common construction that significantly parallels a 1/f or pink noise pattern. Pink noise is said to occur when "each octave carries an equal amount of noise power." And apparently, pink noise over a limited frequency range is ubiquitous throughout nature. (Wikipedia: Pink Noise). For the purposes of the Cornell/Berkeley paper, it should be noted, we are not talking about an audio signal, as we are a pattern.

The paper's authors write:

"The causes for 1/f patterns across the sciences are unclear, but it is now increasingly accepted that there are many such causes (Newman, 2005). In vision, Field (1987) found 1/f spectra in natural scenes, and Graham and Field (2007) found them in artworks. These results reflect the structure of the human visual system. Again, Gilden et al. (1995)—as well as Pressing and Jolley-Rogers (1997) and Van Orden, Holden, and Turvey (2003)—found 1/f spectra in reaction times, and Monto, Palva, Voipio, and Palva (2008) found evidence for their neurological underpinnings. These results seem to reflect the organization and structure of the human mind. Hollywood film might seem far removed from, and not amenable to, this kind of analysis, but we thought not. The 1/f temporal patterning has been found in speech and music (Voss& Clarke, 1975), so film seemed to be another good place to look. Further, we thought we might be able to trace its evolution in film."

And later, explaining their method:

"Our unit of investigation was the shot. Shots are the smallest film units to which viewers are asked to direct their attention. Shot form is sculpted by directors, cinematographers, and film editors. The purpose of that form is to control the viewer’s eye fixations and attention, and filmmakers do this fairly well (Smith, 2006). Shot relations are sculpted by the film editor to promote the narrative (Dmytryk, 1984; Ondaatje, 2004), and these relations create in the viewer what Hochberg and Brooks (1978, 1978) called visual momentum, the impetus to gather visual information. In other words, the rhythm of shot sequences in film is designed to drive the rhythm of attention and information uptake in the viewer. Perhaps the success of these rhythms reflects what Kael (1965) meant by “losing it” at the movies."

I'm not a scientist, but being a commercial music producer, it occurred to me that if modern movies indeed exhibit 1/f patterning, then maybe it is a result of their directors and editors using TEMP TRACKS as tempo maps to facilitate the editing process and 'drive' picture, which has long been an industry practice.

I may be mistaken but I think it may be said that the authors of the study appear to have treated film as a primarily –or singularly– visual medium. As a result, the utilitarian role sound plays in movie making remains unrecognized by the study. Of course, I'm not simply referring to the final musical score created after the fact, but music's use as a pre and post production tool. Those who arrive new to the craft may not realize that directors and editors frequently cut image to temp tracks, and sometimes pre-scores (especially in the case of licensed songs), thereby locking visual edits and actions to pre-existing musical cues; syncing visual events to musical events; rather than the other way around –music to film– which is the common perception (and perhaps traditional method) of how films get made.

Though I can only report on my own experience, there is much anecdotal evidence to support the argument that movies are increasingly being constructed using temp tracks. The process has been going on for decades, but it has become even more common as returns make it clear movies are investments vehicles for those who produce them as much as they serve to entertain the rest of us (i.e., producers who want to guarantee a picture's success will model a new feature on an existing feature, including the score, right down to very last musical cue).

The result is moving picture that is not simply scored with audio as part of the finishing process, but rather a series of images –what the study defines as 'shots'- that are first locked to a predetermined musical pulse, the same way dancers follow music, the same way a band follows its drummer, and not the other way around (usually). In effect, it may be said that the film footage is used as a medium to score the temp track with visual information. Only once that is accomplished is an 'original' score considered. But even when a score is created after the cut is deemed final, it is expected that the new 'original' score will also be modeled on the musical mapping established by the temp track.

It is not quite clear to me if the scientists who produced the study believe 1/f patterning in film an unconscious advancement, or the result of an increased skill set, or if they have any opinion on that matter (beyond their discovery and observation of the phenomena).

Either way, I believe that if modern movies do exhibit 1/f patterning, as James Cutting and his colleagues suggest they do, and no doubt their findings are without error, then maybe it is a direct result of these films being formed upon another construct that also 'resembles the natural rhythms of the brain' – i.e. MUSIC, specifically in its application as a temp track (and tempo map) during the editing process.

* * *


Follow up to my blog entry of 3/2/10 (Hollywood Pink Noise), regarding findings published in the report, Attention and the Evolution of Hollywood Film (by James E. Cutting, Jordan E. DeLong, and Christine E. Nothelfer of Cornell University and the University of California, Berkeley):

As it happens, Professor Cutting was kind enough to write a response regarding the hypothesis presented in my article. I've received his permission to reprint an excerpt from his response here for the benefit of Critical Noise readers who are following this topic. As follows:

"The problem with your account as I see it, however, is that the musical pulse (from temp tracks) that can be used to guide shots (and adjusting their lengths) seems likely only to shorten or lengthen some local shots within or across scenes by no more than a second or so. The 1/f pattern that we found is dependent on correlational structure not only among near-adjacent shots but out to relations across 256, 512, and 1024 successive shots (and across many tens of minutes of film) where music and vocal rhythms would be vastly different across such reaches of film. What we found is not due to just a local pattern. Thus, my strong suspicion is that the effect you suggest would likely effect the power spectrum (what we measured to get the 1/f pattern) only in the range of near adjacent shots.",

–James E. Cutting
Professor, Department of Psychology, Cornell University
(March 2, 2010)

* * *

As a result, it has occurred to me in hindsight that although greatly inspired by Professor Cutting's findings, the 1/f pattern I actually founded my hypothesis upon is perhaps different and separate than the one observed and recorded by Cutting and colleagues –if indeed, the basis of my hypothesis can even be said to follow a 1/f pattern.

In essence:

Does the consistent delivery of (emotional) stimulus via a cinematic medium (produced in part by the use of temp tracks and tempo mapping), itself form a 1/f pattern?

For another day and another study, I suppose.

Terry O'Gara

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