Presentation generally doesn't differ from a regular speech, except the fact that the former might be full of scientific data. This means, in order to help the audience "digest" the information, it would be useful to have more than 2 minutes per slide in the time budget. When demonstrating the results, this quota can even be extended, as the viewers should take a close look at the statistical data.
The author should avoid reading the slides, as they are designed as brief reminders, so it is useful to memorize them, moreover - to be able to say more than the slide shows (otherwise the delivery of the presentation itself is needless). In addition it is impolite to look frequently at the screen, as the audience needs constant visual contact.
Concerning attention-gaining techniques, it is necessary to be aware of the attention span, common for any kind of audience. As a rule, the first 15 minutes of presentation are characterized by careful attention to the details, whereas the viewers' and listeners' attention to great extent switches off in the next 15 minutes. This means, it is reasonable to deliver the information either in 15 or in 45 minutes, as the third cycle of attention span is described as the growth of interest. As a rule, the time quota requires using no more than 20 minutes from the time budget, so the actor should have time to discus the results in the period of the "positive attention. It is also useful to memorize a magical phrase "Let's sum up what I have just said...", which literally boosts the viewers' attention.
In order to maintain the audience's attention, the actor should be able to develop a personal approach to the process (behave naturally and show their own unique traits) and work on its four aspects. First of all, it is reasonable to use gestures in order to place emphasis on a statement, but too vigorous body language is not acceptable when presenting a scientific article or research. The actor should also control their voice and be loud enough to be heard. In addition, in order to prevent the fall of attention, it is useful to change the levels of voice from time to time, as monotonous mumbling is not persuasive at all. Furthermore, maintaining eye contact is critical, but it is counterproductive to look at the same person from the audience all the time. Finally, breath should be controlled, and when there is a direct threat of throwing out, the actor can make a 2-3-second pause and let the audience steep the information into the mind.
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