why does our heart beat faster when we feel nervous?

Answer 1

When you feel nervous, it activates your body's flight or fight system. Epinephrine gets dumped into your bloodstream, causing pupil dilation, reduced blood to your GI tract, and an increased heart rate.

Answer 2

this is due to the activity of what is generally known as the 'fight or flight' response.

when a novel stimulus is perceived, it triggers an activation of brain regions including the thalamus which in turn triggers the activation of brain-stem regions, most importantly the Locus ceruleus.

this activation releases catecholamines, including (but not exclusively) adrenaline, which prepare us to deal with a novel situation with increased attention and readiness.

if the situation is perceived by us to be threatening, we would likely experience fear or anxiety and feel nervous. equally, if we found the novel situation to stimulating in a positive way, the same mechanism would be envoked but the response would be a pleasurable arousal- we would feel excited.

the reason this mechanism exists (and similar mechanisms reside in all vertebrates, not just humans) is that it is an evolutionary adaptation which prepares out bodies to deal with these situations in an appropriate manner.

the release of catecholamines restricts unnecessary organ function like digestion, while making our heart beat faster and releasing vital nutrients to power our muscles to either fight (attack) or flight (get the hell away, quickly).

the only problem is that this response has been hard-wired probably since humans evolved. obviously its more useful if a wild animal jumps out in front of you- less so in modern times when the most stress we tend to experience is having to do something that may be mildly embarrasing.

this is also the reason that its difficult to keep from feeling nervous, even if we don't want to- it happens unconsciously and automatically, we can only deal with what happens after that.

Answer 3

It is a reaction from the body when adrenaline is released. The heart beats faster in order to be ready to react to danger.

Answer 4

When we are nervous, for either a positive or negative reason (eg Passion or fear) we need to be able to anticipate and react to whatever causes the nervousness.

The fast beating heart pushes blood to the lungs and oxygenated blood to the muscles where it may be needed for any quick or powerful response. The muscles need a good supply of fresh blood to work efficiently.

Answer 5

It is called fight / flight reaction or arousal. Basically, when you feel threatened in any way the sub-conscious mind well trigger the body to prepare you to run away or fight to defend yourself. It makes several changes to your body including raped breathing; stomach switches off; heart beat increases. those three make sure blood is pumped to the musicals and organs to power them up with oxygen and glucose (from the liver).

Answer 6

your body tries to function faster and you need more aire to get in, and there your blood goes around quite faster and your heart tries to pump the heart and get the oxygen to your body cells and every part faster, that is why your heart starts beating faster....

Answer 7

Because the human body naturally releases more adrenaline when a person is nervous.

Answer 8

Any emotion you feel induces the brain to react and excrete some chemicals into the blood stream... it all depends which emotion your talking about... when you feel happy... you feel high... when depressed you feel sluggish... after an exercise... that too...

that's how it goes...;-)