I am returning to the topic of PowerPoint (Microsoft Corp., Redmond, WA) slide presentations because of accumulating experience in the year since a I made a previous commentary on this subject . I have just helped organize a scientific congress for 1170 participants with 150 scientific sessions , in which only one of the speakers took the option to use slides. That one talk was a retrospective using archival material from a slide tray. In the other sessions that I attended, I deliberately noted the consistency of formatting, the density of information, and the use of corporate styles. Presentations have become ever more sophisticated, and I am delighted to report that I did not see a single pre-packaged background from the repertoire of Microsoft templates for PowerPoint. Those that I judged as the best slides tended to come from dedicated research institutions—easily deduced from the omnipresent institutional logo, and indicating that a professional graphic artist was likely to be involved. The least professional came from young researchers in universities, but even so I did not see any that were as poor as many teaching slides that I encounter. An easy conclusion is that teaching with PowerPoint would be much better if we were prepared to perform the same sort of vetting that each of these conference talks had been subjected to, that is, professional input in preparation, with peer review and suggestions for improvement. Those conference papers were all from collaborations in research, but teaching is much more of a solo activity. Our egos tend to be rather fragile when it comes to accepting even the most constructive and well-intentioned criticism of our teaching from our peers. Perhaps the answer is for us to take control and simply ask a colleague to review our materials.
The chief faults of the conference presentations were overly dense information and not talking to the content of the slide. I developed a particular aversion for graphical data, particularly histograms with multiple, colored columns and no chance of sorting out the legends before the slide was whisked away. I had experienced much the same feeling at an undergraduate lecture a few weeks earlier, given by a medical colleague, but in this case each student had a handout of the lecture slides so that premature removal of slide data was not a perceived problem (I was trying to follow the lecture in real time). I have observed that possessing a copy of the slides causes a marked difference in audience reaction. Students are remarkably tolerant when they can be relieved of any immediate need to process information. However, it seems that most students still want to write down insightful comments, and I continue to receive salutary feedback from students who have difficulty jotting down information rapidly. I am still learning about the best pauses to moderate a PowerPoint presentation so that the slides become more than a succession of images with a constant sound track.
I was previously reluctant to use a laser pointer , but I have overcome this aversion, and I have found it much better to direct attention specifically to the region of a slide I am talking about. However, getting students to see what I am referring to often requires explicit instructions to look up because I am seeing less and less of my students as their heads disappear down to the photocopy of my slides. Sadly the copies are in information-poor black and white, although they can get the color version later from the Web. This perceived behavioral downside, I suspect, is more my problem than a student problem. In my previous commentary I noted that one of my best-received lectures, in a series otherwise using PowerPoint, was a lecture on nutrition delivered using overhead projection. I gave the equivalent lecture this year using PowerPoint, and it remained the best-received lecture. I have long liked the many freedoms of presenting using overheads, but the time for this technology has passed.