[DoctorBeaver (OP)]

Could it be a promordial thing to alert others to potential danger?  []

[rosalind dna]

But then why do I scream when I am already scared which I do often
then I do worry loads

[Professor Gaarder]

My guess is that it is this:

Fear and anger both cause the release of adrenaline. Adrenaline adds temporary energy to your lung muscles and surrounding areas, making you want to exhale air as fast as possible to release the energy.

But that's just a guess.

[DoctorBeaver (OP)]

You don't need to scream to exhale quickly.

[Professor Gaarder]

I'm assuming the adrenaline would also affect other muscles.

And besides, if you want to scream, it sometimes feels better just to take a deep breath.

[DoctorBeaver (OP)]

I'm sure there's more to it.

[another_someone]

No, I don't see adrenaline as having a role.  Adrenaline is known as a 'fight or flight' response, but most people who scream tend to do neither.

As you say, it is probably an alarm call, either demanding assistance, or causing the flight of others.

[DoctorBeaver (OP)]

Adrenaline is known as a 'fight or flight' response, but most people who scream tend to do neither.

Good point.

[Make it Lady]

I think it is all of these. When people are extremely scared they quite often go into a shock stage which stops them from moving, hence the corruption of the word petrified which means turned to stone. If you are unable to fight or flight you have an excess of adrenaline which is then released as a scream. Knowing that you are a goner enables you to warn others so that they CAN run. I think the whole response to fear is a primitive thing.

[another_someone]

Another thing to think about - who is it who usually screams?  It is usually women and children (yes, I know it is stereotyping, so bear in mind the word 'usually', rather than assume I mean it indiscriminately).

Women and children were traditionally on their home range, and any danger that threatened them was probably also threatening their kith and kin.  If they shouted in response to danger, it would either bring the rest of their tribe to their assistance, or at least give their kith and kin time to flee.

Compare that with a male who might be on a hunting trip, or at war with a neighbouring tribe.  If he screams in response to danger, he would be giving the game away, and the people coming to see what all the noise was about would likely not be friendly to him.

[another_someone]

I think it is all of these. When people are extremely scared they quite often go into a shock stage which stops them from moving, hence the corruption of the word petrified which means turned to stone. If you are unable to fight or flight you have an excess of adrenaline which is then released as a scream. Knowing that you are a goner enables you to warn others so that they CAN run. I think the whole response to fear is a primitive thing.

I am not doubting that it is privative, but still not convinced that in this case it is adrenaline is the driving force (I could imagine that maybe cortisol might have an impact, but cannot say if this is or is not the case, but I know that cortisol is associated with stress, but not with 'fight or flight').

[Professor Gaarder]

No, I don't see adrenaline as having a role.  Adrenaline is known as a 'fight or flight' response, but most people who scream tend to do neither.

As you say, it is probably an alarm call, either demanding assistance, or causing the flight of others.

well then what's the emotion chemical that causes stress?

[DoctorBeaver (OP)]

Another thing to think about - who is it who usually screams?  It is usually women and children (yes, I know it is stereotyping, so bear in mind the word 'usually', rather than assume I mean it indiscriminately).

Women and children were traditionally on their home range, and any danger that threatened them was probably also threatening their kith and kin.  If they shouted in response to danger, it would either bring the rest of their tribe to their assistance, or at least give their kith and kin time to flee.

Compare that with a male who might be on a hunting trip, or at war with a neighbouring tribe.  If he screams in response to danger, he would be giving the game away, and the people coming to see what all the noise was about would likely not be friendly to him.

Very valid points and I think you may have hit the nail on the head.