Yawn…..

•June 6, 2013 • Leave a Comment

I was laying in bed thinking, and had a bit of a mini-revelation about why it is that we yawn, and came up with this:

Yawning is the mechanism by which our bodies equalise the pressure of the the blood in the brain with the pressure of the blood in the rest of the body.

It makes sense to have separate independent control of the cerebral vascular system to prevent any surge overload of the delicate system of blood vessels there. Somewhere in the neck in the main blood supply to the brain there must be some kind of valve or thickening/strengthening point which mediates the blood pressure there and protects the brain from the fluctuations caused by our physical exertions.

When we are getting ready to sleep or are tired or inactive, the heart begins to slow and blood pressure falls. The brain recognises the slowdown, and additionally recognises that optimal alertness/consciousness is no longer required (perhaps steady, higher pressure in the brain facilitates consciousness, and less blood supply leads to sleep. I wrote an earlier entry about this some time ago). It makes sense to equalise the pressures between the two systems, so…. we yawn.

I suspect that the physical action of  yawning is allowing the valve/compression point area of the blood vessels in the neck to dilalte and allow the pressures to equalise (which is the kind of humming/tension sound we can hear near our ears when we yawn), with an immediate release in tension.

Perhaps, then, insomnia is the result of a malfunction of the “valve” which is meant to equalise the two systems, leading to unwanted higher pressure in the cerebral vascular system, thus promoting consciousness.

Anyway, I’m back off to bed….

 

 

 

 

Wake up!

•June 1, 2013 • Leave a Comment

A bit off topic, but I’ve been thinking of a better way to rouse people from comas.

There were a few news stories a year or so ago about Zolpidem (hypnotic) being used to wake people from comas, with some success. Apparently, the technique hasn’t filtered to grass roots level, since there were also stories featuring families who had read of these successes having to prompt doctors (who hadn’t heard of it) to try it on their loved ones, also with many successes.

I used Zolpidem (and its close relative Zopiclone) nightly for a few years, and it has a unique characteristic, which I’m convinced is what makes it useful in these coma cases. When it wears off, usually after 3-4 hours, there’s no gradual wakening; it’s like a switch being thrown to the on position, and you immediately open your eyes, fully aware and wide awake. Its mechanism is via GABA, but I’d be surprised if that we were able to look at the deeper mechanism it wasn’t somehow disrupting blood flow to part of the brain which deals with consciousness (when people stay awake after taking it, it can also lead to hallucinations, which lends weight to this argument).

It’s the sudden end to its action which interests me, the sudden switch-on of consciousness. I imagine a very sudden and dramatic return to normal blood flow, which kick-starts consciousness, as it has been doing for some of those in a coma.

Imagine a garden hose. If you bend it, the flow is restricted, but when you straighten the bend, there’s a sudden spurt as the pressure is released, before the flow quickly returns to normal. It is, perhaps, this sudden spurt which rouses someone from a coma.

I was thinking that if it were possible to coincide the moment at which the effects of the zopiclone wear off with the administration of a systemic short-acting vasodilator like amyl nitrate, the resultant increase in boost effect may rouse those in even the deepest comas.

 

 

 

 

Reality Synthesis….

•May 13, 2013 • Leave a Comment

synth

I’ve thought of a good analogy for the brain, and how drugs or illness can lead to altered perception.

To create a sound with a modular synth, a basic signal is fed in before being routed via cables thought a series of modular processing units. Each module is able to alter the sound, changing the frequency, volume, decay level etc, and by adding effects such as reverb, flanger, chorus etc.  Millions of permutations can be made by altering the positions of the cables, and each repositioning will create a unique sound (indeed, even the order in which the signal passes through the modules will change the effect), which leaves the synth at the other end and is routed to an amplifier, which enables us to hear the finished sound.

Now, think of our brains as a modular analogue synthesizer. An event, be it stimuli via our senses, or created within our minds as thought, is fed in from the left to be processed before going through a series of modular processing units, and out the other side as our perception of that event.

Imagine that each module is capable of being turned on or off by a switch. A sound (or thought) which usually passes through a particular switched-on module may be heard (or perceived) as a flute, but if that same module is switched off, the same sound is heard as a violin. Re-route the cables, and you can distort the violin. In fact, by tinkering with activation of the modules and re-routing the cables, that sound can become pretty much anything you want it to.

People sometimes think of illnesses or drugs as having some kind of magical, ethereal quality. I’d suggest that their effects on perception are merely the result of a similar mechanism to the one described above. The part of the brain concerned with perception is a series of modules, each capable of being activated or deactivated. I suggest that these processing modules are activated via blood flow, and the switch is the neurotransmitter serotonin. Compounds which alter perception have no intrinsic power or magic of their own – all they’re doing is tinkering with the electronics, as it were. For example, a drug may selectively bind to or activate a receptor, effectively activating or deactivating that particular module of perception. Depending on the particular compound, a different set of modules may be activated or deactivated, giving rise to the myriad of different effects experienced. Similarly, illnesses characterised by altered perception are probably the result of disrupted blood flow, although, again, the nature of the symptoms experienced can vary according to the specific modules affected.

synth1

Of course, some of these modules will serve purposes other than data processing. Some will be concerned, via the same mechanism, with switching on or off other “functions” within the body. For example, a message may be sent to the gut for the blood vessels lining it to dilate,  removing more water from the waste, or to the kidneys to process more of that waste water. The key to these functions, both locally and centrally, is the serotonin, which facilitates the opening and closing of blood vessels via its effects on blood vessel tone. That is perhaps why the relative sledgehammer approach of even selective reuptake inhibition comes with such disparate side effects.

Just to recap…

•May 13, 2013 • Leave a Comment

I’m not sure how much of this I’ve ever put on here, and how much is just floating around my head. Here’s a recap of some of the main concepts:

– Blood vessel tone, and indeed blood pressure is not uniform and systemic. Rather, it’s adjusted locally in order to turn on or off functions and processes within the brain and body by allowing or restricting blood flow.

– Blood flow is controlled by the neurotransmitter serotonin. That’s pretty much its sole role.

– Genetic or environmental factors may cause a disruption in normal blood flow regulation, or of the ability of the blood vessels to effectively dilate and contract. Endothelial health may be poor, and the elasticity or ability to react of the blood vessels reduced.

– Alterations in perception can be the result of abnormal blood flow within the brain. For example, states which involve depressive or hallucinatory symptoms may be the result of insufficient blood flow, whilst mania, delusion and insomnia may be the result of increased blood flow. The symptoms exhibited will vary according to the specific area of the brain affected by the alteration of normal blood supply.

– Instability of blood vessel tone leads to varying  levels of mental discomfort ranging from anxiety to psychosis depending on the level of instability. Agents which stabilise the blood vessel tone (for example nicotine, anti psychotics, amphetamine) bring relief, which may help us to understand the mechanism behind some addictions, or at least the mechanism behind cravings and withdrawal.

– Consciousness is dependant upon sufficient blood flow to (unknown) structures within the brain, and the level of consciousness can vary according to blood flow.

– Sleep is merely a mechanism to enable the cardiovascular system to rest, recover and repair. Some of the available serotonin is converted in the pineal to melatonin, leaving less to “keep open the gates” of consciousness. Breathing slows and the body cools. Blood vessels constrict, and the heart slows, needing less effort to maintain circulation at the minimum level required, reducing strain. The reduction in blood flow combined with the vasoconstriction disrupt blood flow to the structures within the brain sufficiently to cause loss of consciousness. Disruption of blood flow to other centres in the brain give rise to the hallucinations which we refer to as dreams (an experiment involving administering psilocybin to volunteers undergoing a brain scan last year found that the substance was reducing blood flow in areas of the brain whilst hallucinations were being experienced)

I’ll come back to this, need to write about something else I was just thinking about…

Vasostressor

•April 25, 2013 • Leave a Comment

I had to think of a new word to describe the action of environmental and other factors in their contribution to the state in which mental illness occurs due to an abnormality in cerebral blood vessel tone.

Vasostressor

Something which either causes excessive or prolonged dilation or constriction of blood vessels within the brain leading to a reduction in or change to their usual level of functioning or their ability to react.

 

 

Vascular Development in the Infant Brain

•February 19, 2013 • Leave a Comment

http://www.eurekalert.org/pub_releases/2013-02/cu-snl021413.php

 

Coffee, Green Tea & Hot Water

•February 12, 2013 • Leave a Comment

I’m just reading yet another article about the relative benefits of tea or coffee as a pick-me-up or to prevent cognitive decline in old age.

I’d suggest the reason that there are so many contradictory results from the large number of studies conducted annually is pretty simple:

The positive effects found are nothing to do with the tea or coffee.  They are the result of hot water hitting the roof of our mouths, prompting dilation of some of the blood vessels in the brain, most likely including those upon whose blood supply consciousness depends.

It’s why coffee wakes us up in the morning. The caffeine may have a mild stimulant effect later, but it’s the heat at work first thing.