I got to discussing slide presentations with a group of friends on Facebook yesterday. Most of them are preachers, and we were commenting on an article about how the Google CEO does presentations (the link is in today’s Links to Go).

The discussion got me to reading again, reminding me of an idea that I sometimes forget when making presentations: redundancy hurts comprehension. I don’t mean the repeating of ideas; I mean the common practice of trying to present information via two channels at the same time. If the information is the same, the brain can’t deal well with the redundancy and copes by not processing the information as it would.

Where this affects churches is in this: if you read a passage of Scripture and project the text on the screen at the same time, people will understand less of what you read and not more.

Surprising, isn’t it? Yet studies have shown this to be fairly consistently true. You can read a fairly recent one here (https://www.researchgate.net/publication/223078244_The_effect_of_redundant_text_in_multimedia_instruction); here’s an excerpt from the abstract:

The results show that whatever the type of text presentation (sequential or static), the duplication of information in the written mode led to a substantial impairment in subsequent retention and transfer tests as well as in a task in which the memorization of diagrams was evaluated.

Logic tells us that projecting a Bible passage while it is being read will allow people to choose to either listen or read. But if we think about it, we know that’s not true. It’s next to impossible to see text on a screen and not try to read it, just as it’s almost certain that we will try to understand something that we are hearing. As our brain tries to do these two things at the same time, it fails miserably.

It’s funny though; when asked if visual/auditory redundancy help them learn, most people respond “yes.” (Note this study on the National Institute of Health website: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4088922/)

So if your church puts Bible texts on the screen while they’re being read, I’d suggest that you speak up and suggest a change. Blame me. Or blame science.