Ancient auditory illusions reflected in prehistoric art?

October 28, 2014, Acoustical Society of America
Prehistoric paintings of hoofed animals in a cave with thunderous reverberations located in Bhimbetka, India. Credit: S. Waller

Some of mankind's earliest and most mysterious artistic achievements—including prehistoric cave paintings, canyon petroglyphs and megalithic structures such as Stonehenge—may have been inspired by the behaviors of sound waves being misinterpreted as "supernatural."

During the 168th Meeting of the Acoustical Society of America (ASA), to be held October 27-31, 2014 at the Indianapolis Marriott Downtown Hotel, Steven J. Waller, of Rock Art Acoustics, will describe several ways virtual sound images and absorbers can appear supernatural.

"Ancient mythology explained echoes from the mouths of caves as replies from spirits, so our ancestors may have made cave paintings in response to these echoes and their belief that echo spirits inhabited rocky places such as caves or canyons," explained Waller.

Just as light reflection gives an illusion of seeing yourself duplicated in a mirror, reflecting off a surface are mathematically identical to sound waves emanating from a virtual sound source behind a reflecting plane such as a large cliff face. "This can result in an auditory illusion of somebody answering you from within the rock," Waller said.

Echoes of clapping can sound similar to hoof beats, as Waller pointed out, while multiple echoes within a cavern can blur together into a thunderous reverberation that mimics the sound of a herd of stampeding hoofed animals.

"Many ancient cultures attributed thunder in the sky to 'hoofed thunder gods,' so it makes sense that the reverberation within the caves was interpreted as thunder and inspired paintings of those same hoofed thunder gods on cave walls," said Waller. "This theory is supported by acoustic measurements, which show statistically significant correspondence between the rock art sites and locations with the strongest sound reflection."

Other acoustical characteristics may have also been misinterpreted by ancient cultures unaware of sound wave theory. Waller noticed a resemblance between an interference pattern and Stonehenge, so he set up an interference pattern in an open field with just two flutes "droning the same note" to explore what it would sound like.

"The quiet regions of destructive wave cancellation, in which the high pressure from one flute cancelled the low pressure from the other flute, gave blindfolded subjects the illusion of a giant ring of rocks or 'pillars' casting acoustic shadows," Waller said.

He traveled to England and demonstrated that Stonehenge does indeed radiate acoustic shadows that recreate the same pattern as interference. "My theory that musical interference patterns served as blueprints for megalithic stone circles—many of which are called Pipers' Stones—is supported by ancient legends of two magic pipers who enticed maidens to dance in a circle and turned them all into stones," Waller noted.

There are several important implications of Waller's research. Perhaps most significantly, it demonstrates that acoustical phenomena were culturally significant to early humans—leading to the immediate conclusion that the natural soundscapes of archaeological sites should be preserved in their natural state for further study and greater appreciation.

"Even today, sensory input can be used to manipulate perception and lead to illusions inconsistent with scientific reality, which could have interesting practical applications for virtual reality and special effects in entertainment media," Waller said. "Objectivity is questionable, because a given set of data can be used to support multiple conclusions."

The history of humanity is full of such misinterpretations, such as the visual illusion that the sun moves around the earth. "Sound, which is invisible and has complex properties, can easily lead to auditory illusions of the supernatural," he added. "This, in turn, leads to the more general question: what other illusions are we living under due to other phenomena that we are currently misinterpreting?"

Explore further: Sound effects inspired Stonehenge: US scientist

More information: Presentation #2aAA11, "Virtual sound images and virtual sound absorbers misinterpreted as supernatural objects," by Stephen J. Waller will take place on Tuesday, October 28, 2014 at 11:40 AM in Marriott 7/8. The abstract can be found by searching for the presentation number here:

Related Stories

Sound effects inspired Stonehenge: US scientist

February 16, 2012

Ancient legends of thunder gods can be explained today with the modern science of sound waves, said a US scientist on Thursday who believes an auditory illusion inspired the creation of Stonehenge.

Designing an acoustic diode

November 1, 2013

Most people know about ultrasound through its role in prenatal imaging: those grainy, grey outlines of junior constructed from reflected sound waves. A new technology called an "acoustic diode," envisioned by researchers ...

The sound of an atom has been captured

September 11, 2014

Researchers at Chalmers University of Technology are first to show the use of sound to communicate with an artificial atom. They can thereby demonstrate phenomena from quantum physics with sound taking on the role of light. ...

Recommended for you

How physics explains the evolution of social organization

June 20, 2018

A scientist at Duke University says the natural evolution of social organizations into larger and more complex communities that exhibit distinct hierarchies can be predicted from the same law of physics that gives rise to ...


Adjust slider to filter visible comments by rank

Display comments: newest first

1.9 / 5 (9) Oct 28, 2014
Are we sure that sound waves can't be used by the supernatural?
2.1 / 5 (7) Oct 28, 2014
Are you telling me they know all this shit, but they don't know what sound is?
2.8 / 5 (4) Oct 28, 2014
Are we sure that sound waves can't be used by the supernatural?

Yes, we are. The supernatural communicates exclusively by telepathy.

Bear in mind that it's been known to cause severe brain rot, so probably best avoid the supernatural all together.
5 / 5 (3) Oct 28, 2014
Trouble with this type of hypothesis is that we have no means of disproving it. Nevertheless, it's an interesting idea...
2.1 / 5 (7) Oct 28, 2014
Conventional scientists have no idea about petroglyphs and the mythological archetypes, because they insist upon conforming all interpretations to the uniformitarian assumption. If there is actual information within these messages, something which should be considered is that it describes a very important event. But, the uniformitarian assumption assumes that nothing incredibly important has actually occurred over human historical times.

Therefore, any messages must necessarily be devoid of any important information at the point of assumption, and all of our ancestors must simply be stupid.

Don't you guys think this is a little bit self-serving? We've basically dictated the conclusion of the analysis at the point of assumption.

This is not a serious approach. The only serious approach to studying etchings in rock is to give them the benefit of the doubt that they are trying to relate something important -- and only then discount it if that's where the evidence leads.
1.6 / 5 (7) Oct 28, 2014
See graphic at

There's actually pretty good reason to suspect that the petroglyphs refer to high-energy electric discharges.
4.3 / 5 (11) Oct 28, 2014
See graphic at

There's actually pretty good reason to suspect that the petroglyphs refer to high-energy electric discharges.

Actually there's a good reason to suspect you're delusional
not rated yet Oct 29, 2014
Nothing applies absolutely to the products of human intelligence.
1 / 5 (2) Oct 29, 2014
Re: "Actually there's a good reason to suspect you're delusional"

You are perhaps referring to Anthony Peratt, not me. What I did, you see, is made a graphic. The research was done by Peratt, author of Physics of the Plasma Universe, former adviser to the Department of Energy on the Nuclear Non-Proliferation Treaty, peer-reviewer for IEEE's Transactions on Plasma Science, scientist at the z-machine (one of the world's largest plasma laboratory) ...

More accurately, this is the person you are calling delusional.

Like it or not, he spent many years traveling the world cataloging these petroglyphs. And when he was done, he created a supercomputer simulation which attempted to reconstruct events, based upon the hypothesis that the drawings represented things which people saw in the sky.

Of course, once word got out, critic Leroy Ellenberger thought it was his duty to launch a letter-writing campaign to shut this line of investigation down.
5 / 5 (2) Oct 29, 2014
Are we sure that sound waves can't be used by the supernatural?

I have a Halloween ghost prop that screams at trick-or-treater's- does that count?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.