Fear of public speaking is also known as "Glossophobia", which is Greek for 'fear of words'. Obviously, speech anxiety does not mean you are afraid of words! What it means is that you are suffering from performance anxiety, which is a form of social anxiety. Also known as stage fright, speaking fear happens when you find yourself in front of an audience giving a speech or presentation while in a fight or flight or freeze state of mind.
When you are in this state the amygdala, which is the alarm center of the brain, has flagged up your current situation as dangerous and as a result, the panic button has been triggered. If you stay in this mode for long enough, you may start hyperventilating and may end up having a full blown panic attack.
Whether you only panic before a presentation or a speech or you get nervous while it's happening or you beat yourself up for making mistakes afterward, public speaking anxiety can have a severe disruptive effect on your life.
Your mind's job is to keep you take your away from pain and drive you towards pleasure. If public speaking has been encoded as a danger by your amygdala, then you most likely will avoid it. Unfortunately, avoidance reinforces the problem so nervousness can quickly escalate into a full-blown phobia.
The consequences can be very distressing:
Whether you are an actor, a musician, a comedian or simply need to give a talk or a presentation at work, sometimes you may feel so nervous about performing or speaking in front of an audience that even the thought produces fear in you and you'd do anything to avoid it. Even the most seasoned performers can experience this, and it is due to the emergency part of our brains (the "amygdala") interpreting your circumstance as a threat and switching on the fight or flight response.