Anticipation of Public Speaking
Public speaking has always presented an important happening. Not only because of the things that are said during it, which are ususally of great significance or have some special meaning, but also because of the anxiety it causes in speakers.
Basics:
Public speaking is the process of speaking to a group of people in a structured, deliberate manner intended to inform, influence, or entertain the listeners. It is closely allied to “presenting”, although the latter has more of a commercial advertisement.
In public speaking, as in any form of communication, there are five basic elements, often expressed as “who is saying what to whom using what medium with what effects?” [1]
People who speak publicly in a professional capacity are paid a speaking fee. Professional public speakers may include ex-politicians, sports stars and other public figures. In the case of high profile personalities, the sum can be extraordinary. [2]
Anxiety is supposed to enhance the processing of threatening information. Here, we investigated the cortical processing of angry faces during anticipated public speaking. To elicit anxiety, a group of participants was told that they would have to perform a public speech. As a control condition, another group was told that they would have to write a short essay. During anticipation of these tasks, participants saw facial expressions (angry, happy, and neutral) while electroencephalogram was recorded. Event-related potential analysis revealed larger N170 amplitudes for angry compared to happy and neutral faces in the anxiety group. The early posterior negativity as an index of motivated attention was also enhanced for angry compared to happy and neutral faces in participants anticipating public speaking. These results indicate that fear of public speaking influences early perceptual processing of faces such that especially the processing of angry faces is facilitated.[3]
In previous research, a physiological pattern of speech anxiety has been established for the periods before, during, and after delivering a public speech. However, no corresponding psychological pattern has been reported. Although strong correlations between psychological and physiological measures have not been found, it seemed reasonable to expect public speakers to exhibit a psychological pattern of speech anxiety similar to the physiological pattern. The results of this study support that hypothesis. The observed pattern is a monotonic function decreasing from the beginning of the speech through the post speech period. [4]
An evaluation of a number of non-invasive physiological measures of stress was conducted, using bank employees attending a two-weak residential course. The stressor involved was the preparation and delivery of a 15-min public lecture. The physiological parameters measured were urinary excretion rates of noradrenaline (NA), adrenaline (A), dopamine and cortisol, the ratio of NA/A, salivary cortisol levels, heart rate and blood pressure. Measurements were taken at 08.30, 10.30, 12.30, 15.30 and 17.30 h on the day of the public lecture and on the following (control) day. The public lectures were given between 10.30 and 12.30 h. The urinary excretion rates of adrenaline and cortisol were significantly elevated immediately following, but not before, the public lectures. The ratio NA/A was significantly decreased and the salivary cortisol levels were significantly increased both immediately before and after the public lecture. Urinary excretion rates of noradrenaline and dopamine, blood pressure and heart rate were unchanged by the stressor. Measurement of salivary cortisol levels, as well as providing a simple, stress free, non-invasive collection procedure, more closely reflects in time the changes in plasma levels of the hormone, not suffering from the large lag-time involved with urinary hormone measurements. Salivary cortisol measurement would appear to be the measurement of choice in human stress studies where individual stress factors are to be identified and studied. The significance of the stress-induced elevation in cortisol and catecholamine levels in the link between illness and occupational stress is discussed.[5]
Background: Recent studies have highlighted the role of right-sided anterior temporal and prefrontal activation during anxiety, yet no study has been performed with social phobics that assesses regional brain and autonomic function. This study compared electroencephalograms (EEGs) and autonomic activity in social phobics and controls while they anticipated making a public speech.
Methods: Electroencephalograms from 14 scalp locations, heart rate, and blood pressure were recorded while 18 DSM-IV social phobics and 10 controls anticipated making a public speech, as well as immediately after the speech was made. Self-reports of anxiety and affect were also obtained.
Results: Phobics showed a significantly greater increase in anxiety and negative affect during the anticipation condition compared with controls. Heart rate was elevated in the phobics relative to the controls in most conditions. Phobics showed a marked increase in right-sided activation in the anterior temporal and lateral prefrontal scalp regions. These heart rate and EEG changes together accounted for > 48% of the variance in the increase in negative affect during the anticipation phase.
Conclusions: These findings support the hypothesis of right-sided anterior cortical activation during anxiety and indicate that the combination of EEG and heart rate changes during anticipation account for substantial variance in reported negative affect. [6]
Normal male volunteers took single acute doses of either diazepam or placebo under double-blind conditions in three simulated public speaking experiments. Measures of palmar sweating and subjective anxiety showed that anticipation of speaking in public increased anxiety relative to baseline and prestress conditions, and performance of public speaking further increased anxiety. A dose-related anxiolytic effect of diazepam on subjective anxiety supported the model’s clinical relevance. Moreover, the intensity of the subject’s public speaking phobia predicted both degree of prestress anxiety relief from 10 mg diazepam and overall anxiety level, regardless of medication, throughout the experimental session. A measure of traditionalism predicted placebo and 5 mg diazepam response during prestress: As in previous clinical trials, high traditionalism scorers reported more relief from placebo, whereas low scorers showed more relief from diazepam.[7]
Conclusion:
Public speaking can cause a great physical reaction in speaker. If a person does not have a high level of self confidence expecting a speach can lead to more sweating, a change in the heartbeat, faster breathing and many even more serious consequences. That is why a proper preparation of both a speach and psychologcal preparation of s speaker are very important.
References:
[1] http://en.wikipedia.org/wiki/Public_speaking
[2] http://www.gspeakers.com
[3] ”Don’t look at me in anger! Enhanced processing of angry faces in anticipation of public speaking” by: Matthias J. Wieser, Paul Pauli, Philipp Reicherts, Andreas Mühlberger
[4] ”A psychological pattern of anxiety in public speaking” by: Larry W. Carlilea, Ralph R. Behnkeb & James T. Kitchensa
[5] ”The physiological measurement of acute stress (publicspeaking) in bank employees”
J.R. Bassett, P.M. Marshall, R. Spillane
[6] ”While a phobic waits: regional brain electrical and autonomic activity in social phobics during anticipation of publicspeaking” by: Richard J Davidsona, , John R Marshallb, Andrew J Tomarkenc, Jeffrey B Henriques
[7] ”Simulated public speaking as a model of clinical anxiety” by: Douglas M. McNair, Laura M. Frankenthaler, Thomas Czerlinsky, Thomas W. White, Stephen Sasson and Seymour Fisher

My job is to make public speaking simpler. I help people who hate public speaking
A major part of the preparation for public speaking should be about understanding the faces of an audience
Often Speakers fail to understand what happening in the audience and why the audiences have blank faces.
As a speaker if we are not careful we carry on using NORMAL conversational skills when we are speaking to a group.
When you have a standard conversation – you normally get nods, smiles, agreements back from the listener however when we speak to a group ALL that changes. All you see is blank faces.
So we start speaking to blank faces and they don’t usually smile (at least not very often) or nod their heads (some people will but again not a lot) so we are left struggling with critical thoughts about our performance. But its a huge processing error – blank faces are normal in audience – they are just listening faces. They have changed from active listeners to passive listeners – its something that should be widely recognised but it isn’t. Notice when you are in audience what you do – do you keep nodding and smiling or do you just listen (and sometimes drift off and think about your forthcoming holidays)
So try not to read people’s faces when you speak publicly because your brain will interpret any sign as negative. There are exercises to help with this that i teach.
Of course there is more to getting your head around public speaking but when I teach public speaking this is the point that helps a lot of people.