**7. Concluding comments**

To avoid advanced hearing loss and instances of hearing loss-related dementia, it is important to recognize hearing loss at an early stage and provide treatment that prevents the loss of haircell or auditory-nerve stimulation. In particular, for those who wear hearing aids in only one ear, speech intelligibility is known to degrade more in the other ear [50, 51]. However, currently popular implanted hearing devices are a fairly large burden for people soon after they become aware of their hearing loss. For this reason, we tend to stick to wearable hearing aids that are easy to be put on and take off. Researches are therefore using the scientific method to remove technical barriers for hearing aids. Further, governments should try to remove other barriers by providing services such as financial support or public qualification for handling hearing aids, and companies that make hearing aids should charge less money. This will help slow down hearing loss and lead to a healthier society.

Cartilage conduction hearing aid, p11 Cartilage conduction hearing aid trans-

Cochlear implant, p8 Cochlear implant bypasses the normal

Conductive hearing loss, p9 Conductive hearing loss occurs when there

Fricative consonant, p12 Fricative consonant is produced by forc-

Full ear, p11 Full ear is uncomfortable feeling when ears

Loudness level, p12 Loudness level [phon] quantifies the sub-

Magnetoencephalography, p10 Magnetoencephalography (MEG) is a non-

Open-fitting hearing aid, p9 Open-fitting hearing aid has an earplug

Positron-emission tomography, p10 Positron-emission tomography is non-

Profound hearing loss, p9 Profound hearing loss is an inability to hear

Effective duration (τ<sup>e</sup>

cartilage.

directly.

middle ear (ossicles).

), p12 Effective duration is defined by the delay

mits sound information by vibrating aural

http://dx.doi.org/10.5772/intechopen.73527

Hearing Aids

167

hearing process and stimulates hair cells in the cochlea using an implanted electrode

is a problem conducting sound waves anywhere along the route through the outer ear, tympanic membrane (eardrum), or

time at which the envelope along the early decay of the normalized autocorrelation becomes below 0.1, and signifies the degree of periodicity contained in a signal.

ing air through a narrow channel made by placing two articulators close together.

are occluded by something, and it emphasize excessively own voice and sound of

jective perception of sound pressure and is calculated by spectral energy applied to the equal loudness chart for each

invasive technique for measuring neuromagnetic signals generated by the brain.

with a significant leak venting for the pur-

invasive technique for measuring a positron (positive electron) emitted by a nucleus after blood flow, metabolism, neurotransmitters, and radiolabelled drugs.

sound even in 90 dB in silent condition.

mastication during a meal.

1/3-octave band (ISO 532).

pose of reducing the full ear.
