Perhaps, but by the same token there is nothing requiring individuals to donate either, hence plasma donation centers offering money for donations. Likewise, sperm banks often offer payment, and if a woman is willing to sell an egg, she can expect upwards of 10k plus medical costs for her troubles.
re: edelfactor, khyber
Long term hearing loss is not usually due to damage to the ear drum nor to the ossicles (middle ear bones). Of course, damaging either of these will result in temporary hearing loss, called conductive hearing loss, but the body can repair minor damage to either in a healthy body (at least damage to the ear drum).
The most common type of hearing loss, presbycusis, or age-related hearing loss, is due to damage to the hair cells in the cochlea. In a healthy adult, the basilar membrane vibrates in time with the incident sound, and causes a deflection of the tiny stereocilia (hairs) sticking out of the top of the hair cells. This deflection results in a change in membrane potential, triggering a neurotransmitter release onto spiral ganglion cells, which then transmit the information in the form of an action potential along the auditory nerve to the brainstem.
Loud noise causes shearing of these stereocilia, literally breaking them off of the hair cell body. When this occurs, the cell's membrane potential is no longer regulated, and neurotransmitter release is constant. This is the reason you will hear a ringing in your ears after exposure to a loud sound. After a short period the damaged hair cell will die. With repeated or chronic exposure to such sound, enough hair cells are lost that hearing is affected.
This loss of hair cells occurs naturally and spontaneously, which is why older folks lose their hearing, and due to the mechanics of the system the high frequency specific hair cells are more susceptible to damage than low frequency, explaining their propensity to be lost first.
Tinnitus, or ringing in the ears, is not well understood, and a great deal of research is being currently conducted, but it is almost certainly due to loss of hair cells in the cochlea (similar to phantom limb syndrome, the brain interprets the lack of input from the cochlea incorrectly).
There are many good references on the web, which I am too lazy to look up right now. Hope this helps.
/ Auditory brainstem research scientist...
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I know Borders had maybe 10 select CDs available for listening, but that's it. to be fair, he did say a record store...
Same here with my loans.
Perhaps, but by the same token there is nothing requiring individuals to donate either, hence plasma donation centers offering money for donations. Likewise, sperm banks often offer payment, and if a woman is willing to sell an egg, she can expect upwards of 10k plus medical costs for her troubles.
meh, the reply was late, and probably too long for most people to actually read...
re: edelfactor, khyber Long term hearing loss is not usually due to damage to the ear drum nor to the ossicles (middle ear bones). Of course, damaging either of these will result in temporary hearing loss, called conductive hearing loss, but the body can repair minor damage to either in a healthy body (at least damage to the ear drum). The most common type of hearing loss, presbycusis, or age-related hearing loss, is due to damage to the hair cells in the cochlea. In a healthy adult, the basilar membrane vibrates in time with the incident sound, and causes a deflection of the tiny stereocilia (hairs) sticking out of the top of the hair cells. This deflection results in a change in membrane potential, triggering a neurotransmitter release onto spiral ganglion cells, which then transmit the information in the form of an action potential along the auditory nerve to the brainstem. Loud noise causes shearing of these stereocilia, literally breaking them off of the hair cell body. When this occurs, the cell's membrane potential is no longer regulated, and neurotransmitter release is constant. This is the reason you will hear a ringing in your ears after exposure to a loud sound. After a short period the damaged hair cell will die. With repeated or chronic exposure to such sound, enough hair cells are lost that hearing is affected. This loss of hair cells occurs naturally and spontaneously, which is why older folks lose their hearing, and due to the mechanics of the system the high frequency specific hair cells are more susceptible to damage than low frequency, explaining their propensity to be lost first. Tinnitus, or ringing in the ears, is not well understood, and a great deal of research is being currently conducted, but it is almost certainly due to loss of hair cells in the cochlea (similar to phantom limb syndrome, the brain interprets the lack of input from the cochlea incorrectly). There are many good references on the web, which I am too lazy to look up right now. Hope this helps. / Auditory brainstem research scientist...