Kinesthesia and Balance

[Foi4895]

I have recently read that we are all endowed with at least 7 senses. These are the five you learn in school, followed by two more obscure ones. Kinesthesia, the body's knowledge of it's position in space and balance.

 

Thinking of these two as senses is only hard for lack of practice. Stop and define the word sense. The body's mechanism for interpreting its environment. Thusly you could include the two I mentioned before. We cannot make out many sounds without visual input to accompany it. Understanding this it should be a simple step to see how Kinesethisia is a sense. Without it our sense of touch would be much less informative on it's own. If touch is the only sense being used we can make out a great number of things, it is what allows blind people to navigate via stick. But without the body's incredibly accurate self radar, the ability to know where in relation to other things, and other parts of the body that allows the blind to change their sense of touch into an accurate mental map of their surroundigs.

 

And balance allows us, using only that sense, to tell in what direction we are being pulled. If we were locked in a sensory deprivation chamber we would still know when we were turned upside down. Anything we use to make a mental picture of our environtment should truly be considered a sense. And we can use our sense of balance to determine pitch, and that is useful in making a mental map.

 

Do you think these are really senses, I have only heard this from a single source, and I don't want to believe it comletely without some outside input.

[Dak]

equilibrium (balance) is definately a sence. the inner ear is full of fluids and 'hairs', and the hairs detect where the fluid is. as the fluid will, by gravity, remain parralell to the ground, the inner ear gives a direct measure of your orientation with reguards to 'down'.

 

Umm... not one of my best explanations, but you can probably see it quite clearly by half-filling a tumbler and tilting it. The knowledge of where the water level is and a bit of extrapolation tells your body how perpendicular it is. that's why you fall over if you spin round (the water carries on spining after you stop and screws your sence of balance).

 

Not so sure that spatial awareness is a sence as such, more of a combination of different sensory imputs being stored in memory as a 3D knowledge of your surroundings, but thats on the assumption that sence = direct input from the outside, which may not actually be the case.

 

I seem to remember hearing about a human sence of direction, having a small cumpas-type-thing in our brains similar to, but less developed than, that found in homing pidgeons, but im not too sure about that tbh.

 

Also, 'touch', i believe, can be split into different sences -- temperature, pressure, and texture (?). but i suppose if your going to be pedantic you could split 'taste' into bitter, sour, sweet, salt, and umami... i guess it depends how you define 'sence'

[Glider]

The vestibular mechanism (semicircular canals) are, as Dak says, fluid filled chambers. However, there are no bubbles in them, so the fluid doesn't maintain a surface parallel to the ground. The semicircular canals (of which there are three) are structured in 3 planes; vertical, horizontal and diagonal. They are illed with fluid and are lined with hairs (villi). These hairs are covered by a layer of mucus which, in turn, contains small grains of calcium carbonate (called otoliths) which add mass.

 

When you turn your head, the fluid in the semicircular canals doesn't move immediately, just as when you spin a bucket of water, the bucket moves but the water doesn't immediately begin spinning too. This differential (i.e. the ralative movement of the fluid within the canals) drags on the villi, bending them and causing the receptor cells to which they are attatched to fire, which tell us that we are moving. Our perception of the direction of motion depends on which canal is sending the strongest sgnal (i.e. the highest frequency volley).

 

If we keep spinning, the fluid in the canals will eventually catch up and when we stop, it keeps moving. This causes the dizziness associated with spinning, which is a result of percieved motion due to the relative movement of the fluid within the canals.

 

The other mechanism is gravity. The mass of the otoliths will cause the villi to bend if we move our heads from the veticle, however slowly, signalling a change in orientation.

 

The other mechanism is proproception. This tells us the relative positions of all our lims and trunk to our head. Every joint contains sensory organs such as stretch receptors and deep tendon spindles. The activity of these receptors tels us the position of the limb relative to the body, and the psition of the body relative to the head. Information from these receptors is processed mainly in the cerebellum (responsible for posture and muscle tone).

 

The really amazing thing I think is the integration of these two sets of information in the vestubular nuclei and cerebellum. This integration means that we know the orientation of our heads in space and the position of any part of our body relative to the head. Regardless of our orientation and movement, we can always point 'up'. Watch a gymnast or a high diver and you'll get an idea of the amount of information being processed and the speed at which it's processed.

[YT2095]

I`de heard similar that our 6`th sense is that of orientation, however I soon dismised this idea when I heard accounts of people being caught in avalanches and buried under snow and having No Idea which was UP (to dig out) turns out the trick to working it out is to Spit into your hand.

 

just a thought

[sabbath]

umm how does that work out yt? how'd you know where up is if you spit into your hand..just wondering..not that i'll be in any avalanche soon though, unless it's a mudslide:D thanks in advance

[kenshin]

umm how does that work out yt? how'd you know where up is if you spit into your hand..just wondering..not that i'll be in any avalanche soon though, unless it's a mudslide:D thanks in advance

 

I think if it falls back on your face then you are facing up else down.Right YT2095?

[YT2095]

that`s more or less the general idea, yeah

[sunspot]

There is periphreal awareness. Any good athlete is aware of things around them, even behind them. This sense may depend on other senses at the unconscious level such as hearing and sight. But there is also a sense of touch without touch. A good good test to see if you have this is to move your hand slowly along the spinal column of another person, from the back of the head to the base of the spine, without touching them. This experiment is based on the seven major energy centers along the spine, some of which can be felt without touching the person. It may be due to magnetic induction within the nerves of the hand. Periphreal awareness may also be partially due to magnetic induction into the nerves of the skin.

[Sisyphus]

You're just making it up as you go, aren't you?

[sabbath]

that`s more or less the general idea, yeah

 

then on to the next question...(after thinking how stupid I was for not getting that at all) I can't picture out a guy stuck in heaps of freezing ice being able to raise his hand and spit into it. there isn't much room as far as I can imagine.

[YT2095]

as instinct most poeple make efforts to cover their face and heads during such an incident, anyway, that`s what you`re taught to do as a way to establish your direction, not All instances are where you`re packed in solid (there`s often small air gaps and pockets) but it IS pitch black! so something`s better than Nothing