Hearing Disabilities – Sensoryneural Deafness

Hearing Disabilities – Sensoryneural Deafness

            Sensoryneural deafness is the most commonly encountered form of hearing disability. It is defined as the loss of response to a specific range of frequencies due to damage to or defect with the inner ear. It can be mild and go almost unnoticed unless looked for, or it can be debilitating in more severe cases.

            Sensoryneural hearing loss is the much more severe form of hearing loss, as it can not be treated. It involves damage to the hair cell receptors for sound in the inner ear.

Almost all adolescents and older suffer from this form of deafness, however this is not within the range of frequencies normally encountered, and goes totally unnoticed. The highest frequencies are easily lost though what is now natural background noise. Humans are now exposed to much more damaging acoustic activity than we once were, we now have some form of noise almost constantly, even lying in bed there is the hum of a machine in the next room, the creaking of the house, the drone of traffic. This constant noise is not something we are biologically adapted for as it rarely occurs in nature. We also deal with much louder sounds than ever before. A single rock concert today puts out more sound energy in a few hours than earlier humans may have encountered in a full lifespan. All of this leads to far more stress than the ear is designed to take. This said, more and more people are suffering from progressive deafness.

 The highest frequency receptors in the cochlea are the first to go, as they are the most sensitive. Through further abuse, a wider range of hearing is lost. Now by the later years of one life it is not unheard of for an individual to suffer from hearing loss severe enough to require treatment. When the frequency range that is required to carry on regular day to day activities is lost, it becomes a problem. Conversation may be difficult, slow due to poor clarity of signals being sent to the brain. The problem is frequency however more than volume, this is why an elder member of the family may be able to understand some people better than others, their voice falls into the frequency ranges that are better processed by the elder.

            Those that have had greater trauma suffer more drastic and notably faster loss. Occupational hazards such as the drone of loud machinery in a factory, the extreme volume levels musicians are now subjected to, or the frequent loud bursts suffered by an artillery soldier have clear and terrible consequences on the inner ear.

           

Music Therapy –

Music Therapy –

Music therapy is a relatively new form of treatment in the medical field. Some consider it a pseudo science; however numerous trials have shown the field to be an effective supplement to traditional care. Music therapy does not claim to singularly cure any form of disease or disorder, however its primary concern is alleviation some symptoms and aiding in the overall comfort of the patient. Music therapy has been shown in trials to help in treatment of high systolic blood pressure, aggregated heartbeat, general stress, minor chronic pain, depression, and sleeplessness. Music therapy has even been shown the help slow and even reverse some memory damage in patients suffering form Alzheimer’s  through the “Kenny-Rodger’s” effect.

Music therapy, or at the very least its unrefined cousin, has been used widely in many cultures throughout history. Native Americans and many other cultures have used chanting and drumming in healing rituals for centuries. The ancient Greeks viewed music as a force capable of healing and aiding the both the soul and body. As far back as biblical times, we read about David playing the harp to ease King Saul of his bad sprits. Even if we do not accept the bible as a reliable historical source, its contents reflect the culture of the time, and show that music was used for such purposes. The first official and scientific applications of music therapy came late in World War II. Music was used to treat shell shock victims with great success, a treatment that is still in use today. (Though shell shock has become known as Post Traumatic Stress Disorder)

Many colleges are now offering full degrees in the subject of music therapy, the first being Michigan State University in 1944. Now there are 77 different colleges offering formal degrees in music therapy accredited by the American Music Therapy Association. (An organization founded by a collective of practicing therapists to promote research and common, safe practice standards.)

The overall goal of music therapy is to treat a psychological element to the patients ailments, thereby translating to alleviation of physical issues just as any other form of psychological therapy functions.

            There are a wide array of methods used, each individual to the patient being considered. Listening to music, talking about it, creating it, even composing are all widely practiced methods.

Sources :

<http://www.wired.com/wiredscience/2009/03/musicheals/>

<http://en.wikipedia.org/wiki/Music_therapy>

<http://www.cancer.org/Treatment/TreatmentsandSideEffects/ComplementaryandAlternativeMedicine/MindBodyandSpirit/music-therapy>

Dissonance

"An unstable tone combination is a dissonance; its tension demands an onward motion to a stable chord. Thus dissonant chords are 'active'; traditionally they have been considered harsh and have expressed pain, grief, and conflict."

—Roger Kamien (2008),

            Dissonance is the musical term for any form of unstable and usually unpleasant sounding intervals, chords, or sounds occurring within music. Dissonance creates tension and stress (usually) to be relieved though resolution.

            Dissonance is perceived in two ways, one is measurable and rooted in our physiology; the second is a product of musical training. The one of the structures of the inner ear that allows us to hear as we do is the cochlea. Within the cochlea are numerous specialized hair-like structures organized in groups that respond best to specific frequencies. The grating and jarring dissonance that arises from very close intervals such as a minor second result from the two frequencies overlapping the areas of the cochlea they stimulate. This creates an unpleasant sound due to the tangled singles the brain is receiving due to this overlap.

            The second form of dissonance is cultured, trained within each of us. As we listen to the music of our cultures, our brain organizes certain rules. These rules are expected to be followed, and when they are broken, or when what we have anticipated does not happen, we experience discomfort. Imagine watching a basketball game. All is going as normal when suddenly a player pulls the ball to his chest and sprints across the court without dribbling. People create an uproar over the foul they have just seen. The rules they have been conditioned to follow, and have come to expect others to observe as well, have just been broken. If a man who had never seen or heard of this sport were to see the same thing, he would likely think nothing less of the traveling player, if anything he would find him clever for trying a new solution to the problem of getting the ball across the court. This is the same thing we experience when we hear an unresolved chord, a suspension gone awry, when a player steps out of the set key, disrupting the harmony. They are products of culture, of our cultivated expectations for music. Most people do not know the rules; however they have listened to enough music to know when something is not right, just as an armature spectator may not know the terms for each foul, or know the hand signals used by the referee; however they can still know when someone has broken the rules.

            Dissonance can be used to convey negative emotion, tension, anger, discomfort, whatever the composer may need. It is often used as a spice to a specific musical moment; however some genres use dissonance as their defining aspects. Some heavy metal and hardcore groups us dissonance to add to the ambient sense of anger, toughness, or evilness of some music. In any case, dissonance is manipulated to strengthen the emotional contours of music and draw the audience in to the music.                                         

Acoustics

Acoustics – an overview.

Acoustics is the study of the behavior of sound within space. The echo-less, dry sound of a movie theater is designed for a specific purpose, to relay as accurately as possible the sounds produced by the speakers, free of reverberation. A cathedral with its vaulting ceilings and stone surfaces is rich in reverberation designed to carry voices and complement the music of the organ and choir. Even the air that we breathe has acoustic properties, and fortunately it serves primarily to transfer sound. Each space has different acoustics properties dependent on the shape, size, contents, and composition of the space. When the compression wave of a sound comes into contact with an object three things happen to varying degrees. The sound can be reflected from the surface, absorbed by the surface, or transferred through the surface.

 Sound is reflected from solid, non porous surfaces such as stone, tile, hardwood, etc. In reflection the path of the wave is simply diverted with only a small portion of the energy lost, continuing to carry the wave’s information. This leads to qualities such as reverberation, or how long a sound hangs in the air. You may find that in an area with high reverberation, speech is difficult to decipher. This is because all of the sounds being produced are muddled together into an almost indecipherable wave. This will not however stop the brain from trying.

Sound is absorbed by soft, porous surfaces. When absorbed, the energy from a wave is used to vibrate the object, not passing though or deflecting. In this process, a very small amount of heat is transferred. If we could totally absorb the full sound of all the screaming fans at the super bowl, we would have garnered just about enough energy to heat one cup of coffee from room temperature. When a room is called “sound-proof” it is simply surrounded by sound absorbing materials, sound is unable to transfer though the walls and out the cracks between the doors. There are often special materials (fiberglass being the most common) in sheets on the walls to absorb any stray sound preventing echo and sound transfer.

Transfer is simple, if an object transfers sound well, the object simply carries the compression wave through it. These objects are often not very dense and contain lots of air; they are light and vibrate relatively easily.

Stutter

A stutter is a condition of involuntary repetition of sounds, words, or phrases. This causes the subject to suffer intense difficulties with communication and relationships. In most cases this is a developmental condition, however after certain damaging events such as a stroke in the auditory centers of the brain relating to speech, a stutter may develop. A stutter has many psychological effects, not as a direct result of the speech, but of the social alienation and inability to communicate ones thoughts that result from the disorder. In the past, treatment has rarely been successful because the disorder was poorly understood, treatment relied primarily on facing ones fears, being put into public situations where they must speak well, memorizing passages, etc. None of these strategies are effective, primarily because of the inherent fear in the subjects of their own speech.

A company has recently introduced a product called "SpeechEasy" intended to help treat uncontrollable stuttering. It takes the appearance of a hearing aid inserted into the ear. However, rather than simply amplifying sound, this device adds a slight delay and pitch shift to incoming sound, most importantly, the speakers own voice. This manipulates a phenomenon of the auditory cortex called the choral effect. The effects of the choral effect are present in everyone; however they are most easily seen and benefited from in those suffering from a stutter.

The choral effect is observed when the speaker is vocalizing in unison with a group, such as when saying the pledge of allegiance, or reading aloud from a text in a group. This tricks the brain into normal function, largely eliminating the noticeable effects of a stutter. The brain is so susceptible to this manipulation that even speaking directly into a corner and hearing the echo from the speakers own voice has been shown to have the same effect.

This can not treat many of the psychological difficulties that often come with a developmental stutter; however the newfound confidence in speech may lead to the resolution of those issues as well.

http://www.speecheasy.com/howitworks.php

http://www.casafuturatech.com/Book/faq.html