[MissMontana (OP)]

Can anyone explain why it is that you get butterflies in your tummy when you are nervous about something or for that matter if you unexpectantly see someone you find attractive?

Thanks []

[neilep]

Hi Toni...Oh...so you've finally glimpsed my pictures eh ? (oh gawwwd...someone get me a bucket !!)

Thats's a good question though.....I don't know a definitive answer but one could hazard a guess that the nervousnous created, causes a psychosomatic effect. Effectively your mental state causes a physical symptom in your tummy area....now why it's in your tummy area I have no idea............

I wouldn't be surprised if it's somehow related to people who are stress freaks (like me)....who later go on to develop ulcers or digestive disorders (also like me...I get bad indigestion)....hopefully Chris or some other nice medical orientated clever person will help here.

'Men are the same as women...just inside out !'  

[MissMontana (OP)]

LOL, it was the Striptease pic that did it, that far away look!!! []

[tweener]

I always thought it was a little rush of adrenalin that caused it. But, hey who am I to know?

----
John - The Eternal Pessimist.

[neilep]

Could not the adrenalin rush also be psychosomatic John ? though I'm sure there are natural rushes of adrenalin too err..I mean non psychosomatic induced .

'Men are the same as women...just inside out !'  

[chris]

"That sinking feeling" - sounds like a song - is the muscles of your stomach and guts relaxing (switching off) so that everything sags down inside and makes you feel strange.

Automatic (vegetative) processes like breathing, blood pressure control and digestion are handled by the autonomic nervous system (ANS) and are not under conscious control.

There are 2 arms to the ANS known respectively as the sympathetic and parasympathetic systems and together they help to co-ordinate the "fight or flight" or "rest and digest" responses.

Fight or flight reactions are the product of the sympathetic system, whilst rest and digest functions are initiated by the parasympathetic system.

Under stressful conditions the sympathetic system switches on; your heart rate increases, blood pressure rises, pupils become larger (for distance vision) breathing becomes more rapid and deeper, your mouth goes dry and you begin to sweat.

At the same time the parasympathetic system is switched off which causes the digestive system to slow to a standstill, and the bladder relaxes so you forget about needing a wee.

Inactivation of digestion is to allow blood to be shunted away from the intestines to other parts of the body - such as  the muscles - to help you run away or fight.

Chris

"I never forget a face, but in your case I'll make an exception"
 - Groucho Marx

[tweener]

quote:Originally posted by neilep

Could not the adrenalin rush also be psychosomatic John ? though I'm sure there are natural rushes of adrenalin too err..I mean non psychosomatic induced .

'Men are the same as women...just inside out !'  

I would assume it would always be phychosomatic in this case - you are psychologically reacting to something that is not obviously threatening, especially when you see someone you are attracted to.

----
John - The Eternal Pessimist.

[OldMan]

quote:Originally posted by chris
Under stressful conditions the sympathetic system switches on; your heart rate increases, blood pressure rises, pupils become larger (for distance vision) breathing becomes more rapid and deeper, your mouth goes dry and you begin to sweat.

The pupils become larger bit got me thinking...would this be why we squint when trying to see something in the distance? Perhpas we squint to reduce the amount of light coming into our eyes so our pupils enlarge?

quote:Originally posted by chris
Inactivation of digestion is to allow blood to be shunted away from the intestines to other parts of the body - such as  the muscles - to help you run away or fight.

OH that is what I was going to suggest in my very non-scientific type terms. Its nice to know your thinking in the right direction every so often! []

-----------------------------
A prism with an intellect, you throw your light selectively.

[tweener]

I think the reason most of us squint to see things in the distance is because we're nearsighted from spending too much time staring at the computer screen.

If the eye worked like a camera, enlarging the pupil would not help with acuity - it would hurt a little bit.  Lenses that open to wider apertures tend to be less sharp wide open than when they are closed a bit, because there is more lens to cause more refraction problems with the light.  But, past about f8, they start getting worse again because of refraction around the aperture blades.  

Of course I don't think any of this really applies to a persons eyes.  The work on the same principle, but the lens and iris are very poor imaging devices.  Most of the acuity is from processing in the retina and brain.

----
John - The Eternal Pessimist.

[chris]

The fight of flight reaction is triggered off by any stressful stimulus, whether that be taking an exam, a phobic response, or asking someone you really like out for dinner. It is the product of higher brain centres that gauge how scary something is, and then unleash these preparatory mechanisms to help you either stand your ground and defeat the problem, or run away.

One of the brain structures crucial to this process, nestling in the temporal lobe of each hemisphere, is called the amygdala. It is essentially the brain's 'fear centre'.

Individuals in which the amygdala has been damaged (by trauma or a stroke for instance), or removed surgically, display fearless behaviour. They have even been know to pour boiling water on themselves because they no longer have the ability to recognise the potential threat posed by dangerous objects.

Changing the subject completely to the issue of pupil size and vision, we squint in order to improve the acuity of our vision. There are several reasons for this. Firstly, many people are near-sighted. Squinting can press on the eyeball and subtly change its shape which can help to overcome some of the effects of an astigmatism. It might also help to flatten out the lens slightly, improving its capacity for long-distance vision. Secondly, and possibly more likely, is the 'pinhole effect'. Some early cameras lacked focusing lenses and used a tiny pinhole to focus light on the film. It works by forcing every point emitting light in the visual scene to form a small point on the film, so the image is crisp. Modern cameras use lenses meaning that they can have a much bigger aperture to admit more light and take a bigger, higher quality, photograph.

When you screw your up eyes in a tight squint you are essentially creating your own pinhole effect, which improves your vision.

Pupil diameter is important to clear vision, particularly close work. Find a willing volunteer, stand in front of them, and ask them to follow your finger in from a distance of about 50 cm from their face to the tip of their nose. Watch their pupils carefully. As you finger approaches, the pupil will shrink and they will also go cross eyed. This is called 'accommodation' and is the pinhole effect in action before your eyes !

"I never forget a face, but in your case I'll make an exception"
 - Groucho Marx

[MissMontana (OP)]

Thanks Chris.

So given the fight or flight reaction, what causes the body to shut in some fearful situations leaving you petrified?

[neilep]

Chris....can you explain what 20/20 vision is ?...is it perfect eyesight ?

'Men are the same as women...just inside out !'  

[chris]

20/20 vision literally means that you see at 20 metres what you should be able to see at 20 metres. Sounds obvious, but that's how visual deficits are expressed.

Many people have 6/5 vision meaning they see at 6 metres what most people can only see at 5 metres. But once your sight deteriorates you start to experience say 10/20 vision - you need to be 10 metres away from something to see what a normally sighted individual can resolve at 20 metres. Hopefully now you have the idea.

Chris

"I never forget a face, but in your case I'll make an exception"
 - Groucho Marx

[neilep]

Thanks Chris.....It's funny how obvious something becomes once it has been explained....cheers.

'Men are the same as women...just inside out !'  

[Broca]

Dora Diller
Jack Prelutsky

"My stomach's full of butterflies!"
lamented Dora Diller.
Her mother sighed. "That's no surprise,
you ate a caterpillar!"

[neilep]

Tee Hee...yummy !!!

'Men are the same as women...just inside out !'