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Kit suggested that I started a new thread on tinnitus, extracing postings from my earlier thread on Body Awareness. So here it is. Most of what is here will have been removed from the earlier thread to avoid duplication, but some will remain to keep continuity. Jim: Here’s my essay on the differences between what I call the natural approach, and the biological approach, using tinnitus as an example. Its needs to be long, but we all know we need to get away from the sound-bite culture, so I am sure you will bear with me – and even read to the end. Kit: “Let me illustrate my thesis by mentioning that I have severe tinnitus (to the extent of being functionally deaf in my L ear) but this is not any kind of problem for me (I have been a meditator for 30-odd years, and awareness and relaxation a special focus). In other words, my mind de-emphasises what could otherwise be maddening. The same techniques can be useful in all similar problems.” Jim: First, some background. It is now clear that the great majority of cases of tinnitus are due to denervation hypersensitivity – i.e., when deprived of its normal input, the central nervous system generates its own activity instead. Therefore although Kit has suggested the tinnitus made him deaf in the left ear, I suggest the causation was probably the other way round. There was probably some earlier hearing loss (maybe so little that it was not noticed), and the tinnitus developed as a result. The hearing loss then progressed further, so appeared to be the result, not the cause, of the tinnitus. The second point I want to make about tinnitus is that many people find it very ANNOYING. It is like those sounds that may not matter to us at first (neighbours’ music, dripping taps, etc) but after a bit they get on our wick, and can become overwhelming. Part of this response is our feeling that the sound SHOULD NOT HAPPEN – but we are helpless in doing anything about it. And it does not need to be very loud for this to happen. In the “natural” approach, this annoyance reaction, which drives the very negative effects of tinnitus, is uncoupled, by meditation or other techniques. The sound remains present, but has become neutral in its effects. This is clearly the method that Kit has used. The advantages of this method are that it needs no equipment or specialist medical input, and the methods developed can be applied to a wide range of situations. Very valuable indeed! Until recently, this was the only approach available. Indeed, when I first developed my own tinnitus a decade or two ago, and went to a friend who was an ENT surgeon for an assessment, and his response was “Just put up with it. I can put up with mine and it doesn’t trouble me.” So it was clearly OK for him. The trouble is, this does not work for many people. It did not work for me, much as I would have liked it to. And when people are told to fix something themselves, when they have come for help and clearly cannot fix themselves, then this can lead to despair, increased stress, and a worsening of their symptoms in a vicious spiral downwards. Tinnitus is sometimes described as so stressful that it leads people to suicide, though the statistics show this only happens in those who are also facing a lot of other stressors at the same time. Luckily I knew therapy was available, and went straight round the corner to the next clinic and got it. This is called Tinnitus Retraining Therapy. For anyone reading this, who has tinnitus, this is what you should be putting into Google to find a practitioner. The logic, backed by data from animal experiments, is that every time we let tinnitus annoy us, the neural connections between the auditory pathways and the parts of the brain that signal annoyance get strengthened. Every time we have tinnitus and it does not annoy us, the connections get weakened. The basis of tinnitus retraining therapy is (among other things) to play a sound through headphones that sounds rather like the tinnitus, but not quite, at roughly comparable loudness, so we can hear both at once. The sound through the headphones does not annoy us, because we can control it if we want, and by directing our attention to that sound rather than the tinnitus, the neural pathways connecting the tinnitus to the annoyance parts of the brain get weakened. The result is that though we can often still hear the tinnitus once the headphones are removed, it does not annoy us any more. And because the neural pathways are getting weakened, the tinnitus might disappear completely – or, as commonly happens, come back briefly (and not annoyingly) only when our attention is drawn to it (by someone talking about tinnitus, for instance). My guess is that Kit used meditation and other techniques to achieve the same uncoupling. Many people however need help to achieve this. The next stage of my own tinnitus journey happened a year or so ago, when my hearing loss (probably as a result of ageing) progressed further, and under this extra challenge, the tinnitus returned. But I was already using the tinnitus retraining techniques on my own as a routine. How could I deal with this new challenge? Here I turned to my scientific training (and I was also inspired I should add by an article in the Weekend Australian that you might have seen, about an American called Moskowitz who conquered his own chronic pain through visualisations - this is also described in “The Brains Way of Healing” by Norman Doidge). It is known that if an area of the brain is deprived of its normal input, neural connections from adjacent areas will invade and initiate their own activity (actually, the connections are probably there all along, but their activity is normally suppressed). In hearing, this means that if a part of the brain that normally responds to signals at say 8 kHz is no longer getting an input, neurones responding to say 6 kHz, will end up activating the area (much of the pioneering work on this was done at Monash). So with the guidance of my audiogram, which showed a steeply rising hearing loss at 8 kHz, I made up a stimulus with its energy concentrated just below this frequency, using the free sound editing program Audacity. I took some music (rather repetitive guitar music) speeded it up so it sounded like a twittering (so it would be meaningless but have temporal fluctuations that would keep the system stimulated), shifted it in frequency and then filtered it, so all the energy was all in the 6 – 8 kHz band, and put it as a loop on my ipod and listened at a level just above detection threshold. I put it on to fall asleep at night, and lo and behold, the tinnitus went very quickly. So this showed how an increased understanding of the physiology could make a cure when other methods had failed. There are a few interesting points I can make now. One is that when I first heard my new auditory stimulus, I felt “YES”! Somehow I felt very welcoming towards it. It was though the sound was an old friend, that I had been wanting to hear all along, and had been missing. I suggest that at long last neurones that had been deprived of stimulation were getting some, and this produced a welcoming emotional response. Similar reactions have been noted by others when their aberrant neural inputs have been corrected. Second point – why can tinnitus be so very annoying? This may seem no-brainer, but once the question is posed, you realise, why is it so different from the other sounds that we hear all the time that do not annoy us? The reason comes down to the neurophysiology. The auditory system, like all other sensory systems, has different components. We have the specific system, which I can liken to a motorway. It is fast and efficient and its job is to get the signals analysed precisely and quickly so that they can be acted on cognitively with minimal delay. But the motorway pathways are surrounded by other pathways, more like country lanes. They are slower, meander, and connect with lots of other pathways (and to other sensory modalities as well). They also preferentially connect to the emotional systems, including attention and arousal which also means annoyance. For reasons peculiar to their cell biology, these pathways seem particularly sensitive to the loss of normal input, and so become particularly hyperactive when deprived. So any stimulus that does get in, will drive the “annoyance” response particularly strongly. This is why tinnitus can be so annoying. Finally, do these findings suggest a drug treatment, so we can just pop a pill and forget about it? (no more hard work!) While animal studies have suggested drugs that might be useful, none in practice have turned out to be particularly effective, or without too many drawbacks. But it is quite likely that one day these studies will show an effective drug treatment. So in summary how do I compare the “natural” and “biological” approaches? The natural approach is simple, low tech, and can potentially be applied to many different situations. However it takes time and discipline and not many people it seems can achieve it. The biological approach needs input from professionals, and costs money, but is usually very effective, even for people for whom the natural approach has failed completely. And one can use it to derive variants (as I did) to deal with situations of varying difficulty. But both approaches have the same underlying logic (almost, anyway - my second approach was doing something different). One could say that the biological approach uses targeted baby steps, devised as a result of understanding the biology, to achieve the same result as the purely natural approach, and that the desired outcome is more easily achievable by a wider range of people. Finally – and here I am going into deep water and may regret it. But why can some people make the natural approach work and others not? Clearly, practice and discipline come into it. But as well as that, there may be some underlying biological variables that we do not know about. My ENT surgeon implied that there was not an issue – dealing with tinnitus came naturally to him. He is (or was then) a nice, calm, social, well adjusted person who could stand a lot of stress – just what is needed in a surgeon who has to perform very delicate and sometimes life-threatening operations for hours on end (life-threatening when they do intracranial surgery). Very different from a scientist like me who has chosen another path, because it suited my own very different basic temperament. Is this a factor? I don’t know. However we do tend to make moral judgements about peoples’ responses to these situations, when in fact it may be driven by basic differences in biology (types of neurotransmitter enzymes inherited for instance). As for a lit review on tinnitus, which Kit mentioned, a little book called "An Introduction to the Phyisology of Hearing" by one James O. Pickles has a few pages on it, though it is not at an introductory level (my little joke - when I was starting to study science, all the most advanced books seemed to be called "An Introduction to..." - implying now you're getting onto the REAL stuff). Jim. Kit: I would love to read your book; I just tried to order it from Amazon, but an error message was returned "we cannot ship to your nominated address". WTF? Jim: First, some background. It is now clear that the great majority of cases of tinnitus are due to denervation hypersensitivity – i.e., when deprived of its normal input, the central nervous system generates its own activity instead. Therefore although Kit has suggested the tinnitus made him deaf in the left ear, I suggest the causation was probably the other way round. There was probably some earlier hearing loss (maybe so little that it was not noticed), and the tinnitus developed as a result. The hearing loss then progressed further, so appeared to be the result, not the cause, of the tinnitus. Kit: This very likely is true and I was going to make exactly the same point about plantar fasciitis: removing what I consider to be the necessary stimulation from one's feet by insulating them from the environment (shoes) is the cause: the brain/neural system needs this information, and 'looks harder' for it by turning up the volume on the signal from the plantar fascia. Hypersensitivity of the plantar fascia is the result. I wonder how much of EDS might be explained by similar mechanisms, and whether the Mast cell activation syndrome difference is the result of this, rather than the cause? Yes please to starting a tinnitus thread, and cut and paste from the threads above. Re. my L ear: I think that both processes proceeded; in the sense that the loudness of the tinnitus increased as well as the deafness increased. One of the reasons I have not had my hearing tested for so many years is that I think the hearing aid technology that does allow one to hear better does not change the tinnitus. The retraining therapy you mention is of interest to me; perhaps we can talk about this some time. (End of extract) Jim.
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This little popular article has been doing the rounds.. very interesting. See HERE. Scholarly article HERE.
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- Plasticity
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