Kudos to some clever students who have discovered an interesting little trick about human hearing and manipulated it to their advantage. According to this Yahoo blurb and NY Times story, kids are downloading an extremely high-frequency ringtone which often exceeds the hearing range of adult teachers. The reason for this is that, as people age, hair cells are first lost in the high-frequency region of the cochlea. Essentially, as we age we are less able to perceive sounds in high frequencies; this begins in early middle age. Kids can hear the ring just fine, as they still possess hair cells in this region.
"When I heard about it I didn't believe it at first," said Donna Lewis, a technology teacher at the Trinity School in Manhattan. "But one of the kids gave me a copy, and I sent it to a colleague. She played it for her first graders. All of them could hear it, and neither she nor I could."
The technology was first developed as a way to repel young store-front loiterers without bothering older patrons. A Welsh security company called the device "Mosquito," and it was initally an annoying 17 kHz buzzing sound.
"Our high-frequency buzzer was copied. It is not exactly what we developed, but it's a pretty good imitation," said Simon Morris, marketing director for Compound Security, the company behind the Mosquito. "You've got to give the kids credit for ingenuity."
If you are interested, I saw that most file-sharing programs (Kazaa, Limeware) have copies of the ringtone available for download. But you didn't hear it from me!
Comments
You can listen to The Mosquito -- or not! -- here:
http://www.bbc.co.uk/wiltshire/content/articles/2006/04/04/mosquito_sound_wave_feature.shtml
Posted by: Theresa | June 12, 2006 4:40 PM
Brilliant! And it's kinda hard to fault students for being smart, isn't it?
Posted by: pough | June 12, 2006 4:51 PM
Is there some part of 'set on vibrate' that these kids don't comprehend yet?
Posted by: Barry | June 12, 2006 5:47 PM
Wow, I can still hear it WOOHOO! Its pretty annoying, actually. As for vibrate, sometimes you can still hear small vibrations, especially in a quiet classroom, perhaps. And this *is* way cooler, I must say.
Posted by: Shelley | June 12, 2006 6:13 PM
I couldn't hear it on my laptop speakers, but I could using a pair of headphones on my desktop. Pretty damn annoying, too.
As for the chart, I'm 50, and my range peaks around 18kHz or so. So perhaps the ages given are averages (means or medians)?
Posted by: wheatdogg | June 12, 2006 10:29 PM
Yeah, the diagram just summarizes average data for age groups. Environmental (or ambient) noise exposure, as well as genes, all play a role in how many hair cells we hold onto as we age. People who use jackhammers or live near airports will lose their hearing faster than those that live in quiet places.....
Posted by: Shelley | June 13, 2006 12:19 AM
Thanks for writing this up, Shelley. I've put up a poll on the topic over at CogDaily, so we can get a decent sense of how many of our readers can hear it (based on other polls, our median age is around 30).
Posted by: Dave Munger | June 13, 2006 9:35 AM
Your site is great
Posted by: nydia | July 6, 2006 12:37 AM
I think that the most succesfuly "Mosquito" ring tones may exploits the noise of the Horizontal Frequency of the TV's!
Yes, the oldier TVīs plays a very loud background noise associated with the Horizontal Frequency Scan. In PAL-M the noise is played at 15.750 kHZ, in NTSC the noise is played in about 15 kHz. The oldier men, who had a Vaccum Tube TV may confirm that the "mosquito" sound was very loud and is natural that they had a loose of hearing this noise due to a long exposure to this noise! New TVīs are very quiet agaist this background noise... so the new generation will guess no losse of hearing those frequencies! Thatīs one reason of why "mosquito" ring tones works!!!
Posted by: Roberto Bekman | December 31, 2006 10:38 PM
The backgound "mosquito" noise was only a bit problem on the oldier TV?s!
Another great problem was the X-RAY emmiting Vaccum Tube in the 15~30Kv rectifing Tubes! My oldier Philips 26" Color TV on 80?s had a Tube with this explicit WARNING! (Yes, i had repaired myself mine TV on 80?s when i was only 15 year old and I saw those warnings)! In 80?s the secure distance of an TV was about of 2~3 meters!
So, a color TV on 80?s was a great piece of trobles!
Posted by: Roberto Bekman | December 31, 2006 11:28 PM