Stories tagged hearing
Pipe down: What's causing all this noise we're hearing down here under the water?
Courtesy Whit Welles“Hey, quiet down up there. We can’t hear a thing down here.”
No, it’s not the lament of some landlord who’s rented out the upper level apartment to a rock-and-roll loving tenant. It’s a case being heard by the U.S. Supreme Court right now pitting whales off the coast of California against the U.S. Navy.
Justices heard oral arguments yesterday on the case. Environmentalists are challenging the Navy’s claim to perform training exercises along the California coast which use extensive and strong sonar transmissions. The sound waves of those sonar blasts can harm whales and other marine mammals, petitioners contend, with sounds that can be up to 2,000 times louder than a jet engine. Some scientists feel that sounds that loud can cause whales to lose hearing loss, bleed on the brain and possibly lead to mass strandings on beaches.
Decision spot: The U.S. Supreme Court is the site of a pending decision pitting U.S. Navy sonar training exercises against the health of marine mammals like whales.
Courtesy Thor CarlsonThe Navy says that strong sonar level is critical to be able to detect submarines that can elude weaker modes of sonar.
Based on justices’ questions and reactions, however, it appears that court is leaning toward siding with the Navy and national security concerns.
Here’s a full report on yesterday’s court session. Justices were pretty upfront in stating their lack of expertise in mammal biology and national defense matters.
So if you had to decide on this conflict, where would you come down on this question? Does the health and a comfort of whales trump national security? Is loud sonar just an unfortunate byproduct of keeping our national interests safe? Share your thoughts here with other Buzz readers.
Tags : 
Ear
Courtesy Wikimedia CommonsA new hearing aid from a Newark, California company is garnering high praise from users who have tried it.
The device called the Lyric seems to overcome most of the negative aspects that have burdened hearing aid wearers until now, such as discomfort, over-amplification or piercing feedback.
Workings of the human ear
Courtesy Wikimedia CommonsInSound Medical, the company producing the innovative device, has made it so it can be placed easily within four millimeters (less than 1/6th of an inch) of the eardrum. This means amplification can be kept to a minimum, creating a more natural sound for the user. For some hearing loss sufferers it could also mean elimination of the need for surgical implants inside the middle ear.
Sponge surrounds the Lyric so moisture can easily escape from the ear canal and not interfere with workings of the hearing aid. When necessary a small magnet is used to remove the device, as well as switch it on or off and control its volume. Battery-life estimates range between 1 to 4 months (pretty wide range if you ask me) and the unit is kept in place around the clock.
But when the batteries do wear out, the entire device is replaced for yearly subscription fee between $2900 and $3600. This seems a bit steep to me but evidently it’s a competitive price in the expensive world of hearing aids, where little of the costs involved is covered by insurance.
At the moment, however, the Lyric only works with about 50 percent of hearing-loss patients due to the narrowness of some folks’ ear canals. But the company says a new model being developed should raise the figure to about 85 percent.
Personally, I have not used the Lyric or any other hearing aid, so I really can’t say how good it actually is, but overall I think this kind of advancement in the technology is always good news to hear.
SOURCE
Researchers at the University of Michigan have restored the hearing of deaf guinea pigs.
Hair cells in the cochlea of each ear convert sound waves into nerve signals. The cells are easily damaged by loud noises, aging, infections, and certain medications. And, once damaged, hair cells don't grow back. But the researchers used a virus to insert a gene into ear cells that made new cochlear hair cells grow.
During fetal development, the gene makes some cells in the ear into hair cells. In other ear cells, called supporting cells, the gene is inactive. But researchers were able to use the gene to convert existing supporting cells into hair cells.
First, they deafened the guinea pigs by destroying their hair cells with antibiotics. Four days later, they used a virus to insert the corrective gene and get new hair cells to grow. The researchers observed increases in the guinea pigs' brain activity when they exposed them to noises—proof that the new cells are working.
Now researchers are studying whether or not the animals can tell the difference between loud or soft noises, or noises of different frequencies. They're also studying animals deafened in other ways, older animals, and animals deaf for longer periods of time before treatment starts. It will probably be a decade or so before the technique can be tried on human patients.
Recent comments
Random space questions
A (dead) pig in the city
Random Question Extravaganza! The first voyage of the Friendventure.
A (dead) pig in the city
Subscribe
I want to learn about
Science Buzz and all related activities
Science Museum of Minnesota, 2004-2008,
except where otherwise noted.
Copyright Information
Add a new comment