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2023-11: Warosu is now out of extended maintenance.

/sci/ - Science & Math

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6267008 No.6267008 [Reply] [Original]

So, I honestly have no idea why this happens, and I tried to google this shit but I couldn't find an answer.

The question is: Why can't I move my fingers quickly in cold weather? I mean ... when it's cold outside, and I'm not wearing any gloves, I find it very hard to move my fingers as fast as if I was in room temperature. The movement of my hand becomes very sluggish and restricted.
Is this because the nerves are getting numb?

>> No.6267022

>>6267008

thats pretty fucking cool. you can even see his extensor digiti minimi :)

>> No.6267031

>>6267022
Any guess for why that shit happen though?

>> No.6267033

The cold constricts blood vessels. Anything more I would tell you would be speculation.

>> No.6267035

>>6267008

I'm going to attempt a guess.

>In the cold your body is sacrificing extremities to keep your vital organs running smoothly

I think it has something to do with less blood flowing in to the fingers or some such.
I'm a retard I know but I've yet to read anything about human anatomy.

>> No.6267040

>>6267022
dont cut yourself with that edge bro

>> No.6267050

>>6267008
Because magnets

>> No.6267056

>>6267031
motorcycle accident
aka road rash

>> No.6267054

>>6267040
It's not even that edgy.

I mean, it's gross as shit, yeah. Not claiming it isn't. I have to look away after a few seconds. But on the other hand, holy shit, it's so COOL! You can see all the little tendon-control cables moving, like some kind of machine with a maintenance panel off!

>> No.6267060

>>6267056
I was talking about OP's question .... the whole "can't move my fingers fast in cold weather".

>> No.6267066

>>6267035

something close to this.

>> No.6267073 [DELETED] 
File: 633 KB, 1357x948, 1388725123396.jpg [View same] [iqdb] [saucenao] [google]
6267073

>>6267035
>your body is sacrificing extremities
>pic related

>> No.6267071

>>6267056
No, too precise. His hand would be shredded. This was a single CUT.

https://www.youtube.com/watch?v=Ri_NYiTYCP8

>> No.6267077

>>6267060
capillary contraction in extremities to reduce heat flow out of the body
cells in extremities start shutting down including pain neurons...is is it much of a leap that motor neurons also shut down?

>> No.6267078

>>6267054
that is fucking awesome, almost makes me want to depigment the skin on my hands or get some cadaver hands like most robotics researchers nowadays
OP sounds like you have a serious medical condition buy some heated gloves

>> No.6267080

The chemical reactions needed take place faster in the optimum temperatures.

>> No.6267081

>>6267078
I do own gloves, but when I go out to smoke, I like to take them off so that I can hold my cigar better.
But I started to notice that when I am smoking outside on a cold night, my fingers start to get sluggish and numb from the cold air. So, I was really interested in knowing what were the mechanics behind this.

>> No.6267085

>>6267073
I found very offensive to post animal getting abuse.

>> No.6267086

>>6267080
>dasitmane.avi
But, how come that other body functions .... such as the heart, brain, and lungs aren't affected? Is it because like one anon mentioned that the body focuses the internal heat to the vital organs?

>> No.6267097

>>6267086
Yeah, basically. Your core's much warmer than your extremities.

But if your core temperature starts dropping (in REALLY awful weather), then those will start to slow down too.

However, by the time you get to that point, you're in serious danger and at major risk of dying of cold.

>> No.6267094
File: 133 KB, 500x500, 1388725654436.jpg [View same] [iqdb] [saucenao] [google]
6267094

>>6267073
How the fuck did that knife cut through the bone? It must have been horrible. God damn shitskin mudslims.

>> No.6267101

>>6267086
yes

>> No.6267103

>>6267078
Aye. I read something recently about "underactuated graspers" in robots, with the unusual characteristic that they don't have a motor for every joint, so they have a number of advantages.

But then I realized that that was how the human hand worked, and I wondered why we hadn't just started off with those designs instead of bothering with fully-actuated hands?

>> No.6267105

>>6267097

Why does your immune system weaken in the cold? Same reasons?

>> No.6267110

>>6267105
it does not
this is a common misconception

>> No.6267114

>>6267105
That's not actually true. In fact, some studies suggest that cold actually stimulates the immune system.

>> No.6267116

>>6267110
How can you explain getting the flu and other shit like runny nose and what not?
>inb4 viral virus infection between humans due to direct contact

So, if a person was on an isolated piece of land, wouldn't that person experience the symptoms of cold?

>> No.6267118

>>6267110

It makes sense that it would. For the same reasons neuron activity would be impaired. Weaker cell function, chemical activity, blood flow.

But then, at the same time, any pathogen inside of you should also be equally hindered shouldn't it?

>> No.6267125

>>6267116
>>6267118

you retards people get sick more often in the winter because everyone spends more time inside in crowded places exchanging germs.

cold does make you get the cold

>> No.6267124

>>6267116
It's because of a viral infection between humans.

Cold weather may be indirectly responsible for colds, however. Vasoconstriction — when blood vessels close to the outside of the body, such as those found in the nose, narrow (so that your precious warm blood doesn't have to waste heat on those less-essential extremities)— leads to dryness. This dryness compromises the nose's ability to filter infections. On returning to warm air, rebound vasodilation occurs, where your hands get pink and your nose starts running as blood returns to it. The cycle continues if the runny nose is severe enough to cause mouth breathing. Bypassing the nose's ability to filter inhaled air, combined with dry indoor air, allows the inhalation of virus-bearing mucus, which may trigger colds and lower respiratory infections.

>> No.6267128

>>6267116
What else happens in winter?

Bad weather, road rage, major shopping holidays, yearly reviews, etc. Lots of stress. And stress DOES weaken the immune system.

Also, building air is heated and recycled to keep people warm. If one guy has a cold, his virus is getting recirculated through the ventilation system and everyone gets exposed.

Finally, few people wash their hands properly, if at all. Wipe your runny nose with your hand, touch a doorknob. The next person to touch it will have your cold virus on you.

Basically, the winter months make transmitting diseases of any kind incredibly easy.

>> No.6267132

>>6267124
>>6267125
>>6267128

So, if a person was on an isolated piece of land, wouldn't that person experience the symptoms of cold?

>> No.6267138

>>6267128
> Also, building air is heated and recycled to keep people warm
ummm no it isn't.
air has to be brought in from the outside so you don't suffocate and stuff.
I'd put a heat exchanger between the inflow and outflow air, but it's a poor decision to just mix the two.

>> No.6267142

>>6267132
Depends. Do you mean cold as in "low temperature" or cold as in the disease, the common cold?

If you mean the first, yes.

If you mean the second, probably not.

>> No.6267143

>>6267132
no...because a cold is a virus infection.
no virus; no cold

>> No.6267146

>>6267132

If a person were isolated on an island, the virus would have to be there with him in order for him to catch a cold. He might show common symptoms such as a runny nose during the winter, because that's normal body response to temperature. But if there's no way for the virus to reach him then he wouldn't experience the complete symptoms.

>> No.6267152

>>6267142
I meant that if you had a small population on an isolated land who have never been in contact with any other humans through out history, would those people experience the "disease" of getting cold? Would they start coughing and have runny noses? Would they actually die if they were visited by say ... a bunch of americlap pilgrims?

>> No.6267156

>>6267152
>would they start coughing and have runny noses

Yeah, that's just an anatomical reaction, not a viral one.

>> No.6267160

>>6267152
> Would they actually die if they were visited by say ... a bunch of americlap pilgrims?
yes.
http://en.wikipedia.org/wiki/Columbian_Exchange
didn't end well for the Americans

>> No.6267165

>>6267156
If coughing and runny noses are not caused by the virus, then what exactly does the virus do? Does it just weaken the immune system in general? Like, does it just affect the immune system without any noticeable symptoms? In other words, can you be carrying the virus without showing any cold symptoms?

>> No.6267173

>>6267165
The disease, the "Common Cold", and the anatomical effects of getting cold have different causes.

Runny noses and coughing are ALSO common immune reactions. Runny noses to flush out infected mucus, coughing to dislodge it from the airways.

If you eat something you really hate, you might throw up. If you get the flu, you might throw up. That doesn't mean the vomit response is caused by a virus in all cases.

>> No.6267174

>>6267173
Basically, the virus tries to replicate itself using our body's cells. Our body doesn't like that very much, and triggers an immune response, and that immune response forms the bulk of the symptoms of the common cold.

>> No.6267178
File: 20 KB, 280x289, 1388727686502.jpg [View same] [iqdb] [saucenao] [google]
6267178

>> No.6267180

>>6267116
Runny nose is an adaptation to cold weather.

The flu virus can be thought of as having a buttery outer shell. When it's cold, this stays solid and can survive indefinitely. When it's hot, it quickly melts and dies in the environment. Also in cold weather people stay in close quarters which spread disease. Add in the stress / depression / lack of outdoor exercise weakening their immune systems.

>> No.6267179

>>6267174
b-but virus are not alive

>> No.6267200

ya'll niggas need some vitamin C.

>> No.6267208

>>6267200
Dat doubles

>> No.6267226

>>6267116
Furthermore, many sicknesses such as the flu are more active and thrive in colder temperatures.

>> No.6267229

>>6267226
refer to >>6267179

Viruses can't "thrive" without a host. So, I don't see how the cold weather help them thrive. Unless of course you were talking about secondary causes such as humans being in closed heated indoors.

>> No.6267258

>>6267086
internal body is always undergoing homeostasis, tweaking internal conditions in order stabilize health and function.

>> No.6267266

>>6267008
surprised nobody has mentioned edema.

>> No.6267299

>>6267266
Why do you think it's relevant?

>> No.6267322

>>6267116
>>6267114
>>6267124
>>6267105
>>6267125
>>6267143
>>6267142
>not just posting the asapscience vid
http://www.youtube.com/watch?v=RWiOhlqEDz4

>> No.6267341

>>6267299
because it's an extremely common symptom in cold digits and it slows movement and further restricts blood flow.

>> No.6267798

>>6267071
Maybe a cadaver for studying, or an operation of some sort on a live mate.

>> No.6267912
File: 98 KB, 300x300, 1388767132106.jpg [View same] [iqdb] [saucenao] [google]
6267912

>>6267178
Getting back to the original question
>Why can't I move my fingers quickly in cold weather?
I've learned that it has to do with homeoviscous adaptation of the membranes of nerve cells. The membrane of cells need to maintain a certain level of fluidity regardless of temperature and cells accomplish this by modulating the packing of lipids in the membrane. The colder it gets, the looser the packing, the warmer, the tighter.

This keeps the fluidity of the membrane static, but it has the side effect of modifying the permeability of cells. For nerve cells which rely on a constant electrochemical gradient to function, the increase in permeability the cold brings results in a loss of this gradient, and the nerve cells work less efficiently.

tl;dr cold causes nerve cell membranes to become loosely packed and more permeable, resulting in a loss of their electrochemical gradient and function.

>> No.6267923

I don't know how much this is proven, but I'm fairly certain that blood flow effects nerve sensitivity and feeling, and obviously the cold reduces blood flow to the hands.

I have been taking pills to increase my blood flow, and my penis is vastly more sensitive now. How is the blood affecting the nerves like that?

>> No.6267925
File: 51 KB, 450x450, 1388767658645.jpg [View same] [iqdb] [saucenao] [google]
6267925

>>6267912

>> No.6267949

>>6267923
Everything about nerves really comes down to their electrochemical gradient. Maintaining it is really hard, and costs a lot of energy, which is why the brain uses a significant portion of the bodies energy supply.

Lack of blood means lack of oxygen, which means less energy produced by the cell. Less energy produced ultimately results in the electrochemical gradient not being maintained. This is how strokes and heart attacks cause damage.

Unless you're really fucking cold though, there should still be enough blood supply to extremities to keep cells alive and nerves functioning.

tl;dr Nerves require lots of energy in order to maintain electrochemical gradient. Lack of blood means lack of energy means lack of gradient. Normally this results in cell damage however.

>> No.6267966

>>6267912
>>6267949

http://www.ncbi.nlm.nih.gov/pubmed/23933600

found this and apparently heat increases flexibility/ease of motion, cold does the opposite, the % of change is like 25%

>> No.6269293

Is this thread still alive?

>> No.6269314

The cold weakens and slows down our immune system.

I wouldn't be surprised if this applied to the nerves in your fingers. Just a quick and simple answer

>> No.6269321

>>6269314
But would this mean that after cooling and warming the fingers several times in a row ... would that actually damage the nerves in the long run?

>> No.6269725 [DELETED] 

As I understand it, temprature effects nerve function. I recently had and EMG test done and they heated my legs with warm blankets prior to measuring my nerve conductivity. The neurologist said that coldness would affect the motor and sensor nerves.

>> No.6269729

As I understand it, temprature effects nerve function. I recently had and EMG test done and they heated my legs with warm blankets prior to measuring my nerve conductivity. The neurologist said that coldness would effect the motor and sensor nerves.

>> No.6269730

>>6269314
> The cold weakens and slows down our immune system.
This is untrue

>> No.6270093

OP my brother!

You might have Raynaud's Syndrome

I have it too. I play guitar and if the temperature drops too much I can't play for shit

>> No.6270109

>>6270093
He didn't mention anything about hisfingers changing colors.

>> No.6270371

>>6270093
Yeah bro, just like this anon >>6270109 said, my fingers don't change colors.
I was just wondering about the mechanics of the whole thing, that's all.
I hope you feel better anon.

>> No.6270567

>>6267341
Is this what happens when joints hurt when you're cold?

>> No.6270571

>>6267966
>full article from medscimonitor
>199 for educational
>599 for commercial
>personal copy is free

I love this.