Friday 27 April 2012

Did you know? #3


The emperor of Rome, Hadrian 76 to 138 AD who inherited fame for building Hadrian's Wall in Britain, had to cup his ears to hear orders repeated because of hearing difficulties, as recorded in contemporary court descriptions.

Tuesday 10 April 2012

Inner ear memory


Our ears still hear sounds even after the sound source has stopped. Researchers have found that sounds create after-vibrations in our inner ear and these vibrations, in all probability, function like a form of short-term memory.

It has always been assumed that the hair cells in the inner ear only moved when they were directly affected by sounds. The study has, however, shown that there are after-vibrations in the inner ear. How long the small hairs move after the sound depends on the strength of the sound and its frequency.

The goal of these after-vibrations, according to the research team, could be to function as a form of mechanical archive or short-term memory in the inner ear. The researchers believe that the after-vibrations can have an effect on our ability to perceive sounds and language. The ability to detect brief gaps in an ongoing stimulus is critical for speech recognition. Even a minor hearing loss can lead to a substantial reduction in these after-vibrations and that would mean it is more difficult to perceive the small gaps in an ongoing stimulus, which in turn would have a bearing on speech recognition.