(Musical) Silence

Source

Galloway, L. (2012, October 23). The quietest place on Earth. BBC Travel. Retrieved from http://www.bbc.com/travel/blog/20121022-the-quietest-place-on-earth

Summary & Commentary

          According to the Guinness Book of World Records, the “quietest place on earth” is an anechoic (echoless) chamber at Orfield Laboratories in Minneapolis, USA.  Its lack of echoes is credited to its construction.  After walking through two vault doors, one-metre long foam wedges line the room’s walls, ceiling, and even bottom; one must walk on a “floor” made of a trampoline-like mesh.  Virtually no sound is reflected off of the walls, which absorb 99.99% of all noise.  High-frequency sounds are directly absorbed by the fibreglass wedges, and low-frequency sounds bounce in between the wedges until they fizzle out.  As a result, its sound level is -9.4 dB (decibels)—humans can only detect sounds above 0 dB.  The decibel level of a room that an average person would consider to be “quiet”, for example, is 30 dB.

In the chamber, not only can you hear a pin drop, but you also start noticing the frenzy of activity that is going on inside your own body.  People have reported hearing their lungs breathing, their own heartbeat, their stomach digesting food, and even hearing the blood rush to their head and back through to their body.  Even ears themselves make sounds in the echoless room.  Steven Orfield, founder and owner of Orfield Laboratories, explains: “The ear is like a microphone and a loudspeaker. And when it is deprived of sound, it produces its own sounds.” (Weber 2012).  Orfield is talking about otoacoustic emissions (OAE) which are sounds generated by various cellular and mechanical processes in the inner ear, and usually go completely unheard by the unknowing public.

Even after about five minutes in the room, people become disoriented, dizzy, nauseous, and feel like there’s tremendous “pressure” on their head.  “What seems to be happening is you are feeling some pressure in your ears,” explains Orfield, “but what you’re really feeling is pressure being taken off of your ears. Sound is technically called sound pressure level. And in this room we’re actually taking huge amounts of pressure off of your ear, so it’s highly sensitized by not being loaded with normal amounts of noise.” (Weber 2012).  People who visit the anechoic chamber usually sit in a chair.  Standing up and moving around becomes increasingly difficult because we rely so heavily on sound to keep our balance.  Walking feels strange because we have no aural reference (or if one is inside the room in the dark, no visual cues either) for mobility.  Without any feedback from the outside world—like the sound of your own feet moving, for example—uninterrupted action is almost impossible.  The chamber also causes many to feel claustrophobic.  Usually reverb or echo tells our auditory system that there is an ample amount of space, thus the complete absence of echo can instinctively send us into a panic.

          Furthermore, once you lose certain sensations, other perceptions become heightened.  A complete absence of noise can lead to a heightened sense of smell or touch, but can also cause your hearing to become much more sensitive.  As we already know, the auditory cortex sorts, organizes, and simplifies sounds.  And many of the bodily noise people report hearing in the echoless chamber would normally be victim to habituation.  We don’t need to hear these things when we’re out in the world and have to be aware of cars, animals, weather, other people, etc.  But when all of those stimuli disappear, undetectably quiet sounds seem louder, as if our brains have recalibrated to the new noise levels.  People have even reported hearing aural hallucinations, although none of my sources have described the nature of them in detail.

          How quiet is too quiet?  For people with sensitive hearing, the chamber might indeed be too quiet and they would have to get out of the room immediately.  The longest amount of time anyone has been able to spend in Orfield Lab’s anechoic chamber without panicking and needing to leave is 45 minutes.

Reflection

          This article made me think about the relationship between silence and music in two different ways: (1) musical auditory hallucinations as a result of silence, and (2) the idea of “musical” silence, or, periods of silence in between notes, phrases, or pieces, inserted for artistic purposes.

As previously mentioned, it is a shame that the alleged “auditory hallucinations” people have had in the Minneapolis anechoic chamber aren’t better documented. What do people come to “hear” without any outside stimulation when left in complete silence?  Do people ever perceive music that isn’t really there? Is it easier to remember or vividly visualize music in silence? Maybe because we’re so used to hearing everyday sounds, that when all of it is taken away we try to make up for what we’re accustomed to by creating the sounds ourselves?  After all, the healthy population is fully capable of recreating sounds—whether it be voices, street noises, or music—in the mind’s ear with minimal effort, so it’s not a far leap to say it can sometimes occur involuntarily due to sensory deprivation. 

          An echoless room is essentially a variation on John C. Lilly’s sensory deprivation tank, which he invented in 1954.  A physician and neuroscientist, Lilly aimed to isolate the brain from any external stimulation.  The small tank, which closes shut to stop any light from getting in, is filled with warm salt water allowing for a subject to float for extended periods of time.  The sensory deprivation tank operates on the principle that in total absence of external stimuli, the human brain creates its own perceptions.  The idea of perceptual isolation is known today as the Restricted Environmental Stimulation Technique (REST) which can occur in a room or in water.  Even with the psychological and neurological research done with REST, there are very few findings about auditory hallucination—or hallucination as a result of sensory deprivation—that doesn’t cross over into issues of psychosis (see Nayani & David 1996; Na & Yang 2009, for example).

Now, knowing everything we’ve just learned about our brain’s reaction to silence, what are the potential applications of silence in music?  And how can silence be used in music for artistic or dramatic purposes?  In “Moved by Nothing,” Margulis explored five functions of silence in active, participatory music listening: (1) silence as boundary, (2) silence as interruption, (3) silence as a revealer of the inner ear, (4) silence as a promoter of meta-listening, and (5) silence as a communicator.  She says that “since literally nothing happens for the extent of the duration of the silence, all of our various percepts, reactions, surmises, and senses reveal things we have brought to the silence.” (Margulis 2007, p.246).

In a setting where one has consciously sat down to listen to music, silence can be extremely powerful.  Like the commanding silence before the beginning of a piece, for example, where every attentive ear is hypersensitive to the slightest sound, getting mentally ready to hear what is to unfold before them.  In line with the anechoic chamber discussion, sounds emerging from silence are actually better processed by our brains, as the search for an auditory stimulus activates the auditory cortex (Voisin et al. 2006).  Moreover, EEG (electroencephalography) and MEG (magnetoelectroencephalography) tests show the brain’s detection of musical phrase boundaries shortly after the phrase’s offset, suggesting that listeners spend these silences synthesizing the preceding musical phrase and refocusing their attention on hearing the subsequent one (Margulis 2007, p.253).

Just like in a sensory deprivation tank, when auditory stimuli are removed in the context of music-listening our own personal auditory imagery, visualizations, imaginings, assumptions, and expectations come to the fore.  Musical silence can definitely serve to encourage this process, additionally acting as a sonic boundary that guides our auditory attention.

References

Margulis, E. H. (2007). Moved by nothing: Listening to musical silence. Journal of Music Theory, 51(2), 245-276.

Na, H.J., & Yang S. (2009). Effects of listening to music on auditory hallucination and psychiatric symptoms in people with schizophrenia. Journal of Korean Academy of Nursing, 39(1), 62-71. http://dx.doi.org/10.4040/jkan.2009.39.1.62

Nayani, T. H., & David, A. S. (1996). The auditory hallucination: A phenomenological survey. Psychological Medicine, 26(01), 177-189. doi:10.1017/S003329170003381X

Veritasium. (2014). Can Silence Actually Drive You Crazy? YouTube. Retrieved from https://www.youtube.com/watch?v=mXVGIb3bzHI

Voisin, J., Bidet-Caulet, A., Bertrand, O., & Fonlupt, P. (2006). Listening in silence activates auditory areas: A functional magnetic resonance imaging study. The Journal of Neuroscience, 26(1), 273-278.

Weber, T. (2012, June 21). In Minneapolis, the world's quietest room. MPR News. Retrieved from http://www.mprnews.org/story/2012/04/03/daily-circuit-quiet-room.