I think that I am most engaged when I have something like a PowerPoint to look at. Even if it doesn't include pictures or anything, I think seeing bullet points, or what is being said in writing, is beneficial for me when it comes to keeping my attention on the presentation. This is especially useful in a classroom context to take notes when I am often asked to recall information that is talked about.
I feel the same way about how presentations help people stay more engaged. Great job!
I definitely agree, slideshows keep me from falling asleep. Something to look at makes my ears open up a little wider, helping me store info better.