Powerpoint can damage your health (seminar)

If you've ever been to a conference — and let's face it, the health sector thrives on them — you'll have seen a Powerpoint presentation. Chances are that your eyes have then slowly glazed over and you've started panicking about overwork and dosing yourself up with caffiene.

But fret no longer. Dozing off during PP presentations has a scientific explanation. Research from the University of New South Wales has shown that reading information on a screen at the same time as listening to a speaker saying much the same thing overloads the brain which simply switches itself off.

Professor John Sweller told the Daily Telegraph that simply talking could be more effective. 'The use of the PowerPoint presentation has been a disaster. It should be ditched. It is effective to speak to a diagram, because it presents information in a different form. But it is not effective to speak the same words that are written, because it is putting too much load on the mind and decreases your ability to understand what is being presented.'

Professor Sweller is the founding father of so-called cognitive load theory, the three principles of which are as follows:

• Working memory is limited when you're learning new information. Only once information is in long-term memory can it be brought back to working memory in very large amounts.
• In a classroom-type situation, only limited material is going to be retained, unless notes are taken or handed out.
• Power-point presentations can backfire if the information on the screen is the same as that which is verbalized, because the audience's attention will be split between the two.