Today’s post had better be a quick one. The desk research in the background is getting complicated and I have just ordered a 900 page book on Human Physiology, so as not to spout complete nonsense. Worse still, a couple of days ago, I received in the mail, a big brown envelope from Tokyo with a juicy report on the use of Ceredist, a TRH analog. It is 20 pages long, and the bad news is that 18 pages are in Japanese. The good news is that I had expected all 20 pages to be in Japanese.
The star of course is “Monty”, aged 9.
His supposedly “typical” big brother,
aged 12, is going to be called “Ted”.
Head of Applied Research, part-time
biker and Speech Therapist will be called Dule (“Doolay”)
Last week I decided that it was time for some good
old fashioned primary research, to test a hypothesis that I had formulated. This is what we presented to the in-house ethics
committee, for approval:-
1. Many children with autism exhibit what appears as sensory overload. On hearing a moderately loud sound, they will
cover their ears, almost as if in pain.
Bright lights, darkness, certain smells, even touch can trigger similarly
strong reactions. Entire books have been
written documenting these odd behaviours, but I never read an explanation for
them.
2. In my trawl through the literature, I noted that a disorder with surprisingly similar symptoms has been documented -
Hypokalemic sensory overstimulation
This disorder manifests itself as an
overwhelming feeling of sensory stimulation.
But then disappears 20 minutes after a dose of oral potassium. A related, but much more severe,
disorder that causes temporary paralysis also exists - Hypokalemic periodic paralysis
3. The recommended daily amount of potassium for adults is 3,500mg. A typical banana contains 400 mg of
potassium. A dissolvable tablet of Potassium Citrate contains 500mg of
potassium. So 500mg is a safe dose to experiment with.
4.
A laboratory
experiment is proposed using an MP3 file of a baby crying. Dule will first establish a baseline volume (VB) at which Monty will cover his ears. Monty will
be sitting in a fixed position in the lab. This test will be repeated over a
few days to see if VB varies.
5.
Then the
subject will receive 500mg of oral potassium and wait for 20 minutes. The MP3
file will be played again while he is sitting in the identical test
position. Dule will crank up the volume and note the new threshold volume (VT).
6.
The same test
will be repeated with Ted and Dule as subjects.
Prior to providing Dule with the oral potassium solution, Peter suggested to Dule that he would perhaps prefer
if the test did not show up anything worthy of further investigation. Since that would again drive Peter crazy, that
no serious scientist had noticed this, done something about it and published their work.
Here is the raw data from the test:-
Volume * at which sound becomes disturbing
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7-Mar-13
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8-Mar-13
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11-Mar-13
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11-Mar-13
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after
K+
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Monty
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9
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9
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9
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16
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Ted
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23
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26
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Dule
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21
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23
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* sound level on digital display of Philips mini HiFi
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room is about 20 m2, subjects were 2.5 m from HiFi unit
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As you see, Monty is far more sensitive to sound than both Ted and Dule. Monty experiences a sharp increase in his capacity to cope with sound stimulation after drinking the potassium. Ted and Dule show a small increase in capacity, that may be just down to measurement tolerance/error. (Dule was testing himself, after all)
The cause is related to something called VDCC (voltage dependent calcium channels) these are like little valves that open to let Ca2+ ions in or out; they are misbehaving. Recall that Bumetanide works in a similar way by triggering NKCC1 and NKCC2 (Sodium, Potassium, Chloride Cotransporters) to let in/out Cl- ions. The subject of misbehaving ion channels has already been given a fancy name by scientists, its Channelopathy. Now I was wondering how I was going to explain my use of French in this post. It's all about the English Channel or should I say la Manche, and so we'll call it Manchopathy.