The Digital Signage Insider

Making great digital signage content: Get better recall with chunking and coding

Published on: 2008-03-25

Continuing our series on how to use mnemonic tricks to make your digital signage content more memorable, today I want to talk about chunking and coding. This is another simple effect that you can take advantage of to improve the recall rate for the messages on your screens.  Like the serial position effect that we covered last week, chunking and coding relies on specially ordering the items in a list to make them more memorable. It also leverages some innate features of human memory to reduce the amount of "effort" a viewer must expend in order to understand, and later remember, your message.  Properly chunked and coded messages can be recalled at 2-3 times the rate of similar but unoptimized messages, so this approach is especially handy if your screens are placed in locations where they compete for attention with other stimuli (which, unless you're putting them into sensory deprivation tanks, is basically everywhere). So if it's your job to put text on a screen and get people to remember what it said, chunking and coding is definitely something you'll want to know about and use to your advantage.

Way back in 1956, Harvard professor George Miller published "The Magical Number Seven, Plus or Minus Two: Some Limits on our Capacity for Processing Information," a rather bland-sounding psychology paper that would go on to become one of the field's true classics.  Miller noted that virtually everyone has an upper limit on the number of items that they can commit to memory in a short amount of time.  That upper limit is five to nine items (or 7 +/- 2, if you like), and it seems to transcend gender, age, culture and race, thus making it a particularly good target to optimize for. Go much past this number, and the accuracy of recall goes down dramatically. In other words, if you ask the average individual to recall 15 things, you might as well be asking them to recall 50 items.

What does this have to do with making great content, you ask?  Well, as I mentioned last week, great content starts with great copy, and the arrangement of that copy can dramatically impact how much or how little your viewer will remember. Your content may relay several messages in a list, or you might ask viewers to remember a coupon code, phone number or SMS code. In each of these cases, even a simple modification to how the information is presented can have a significant impact on how much the viewer will remember later.

To begin with, let's talk about data chunking. Quite simply, chunking is a way of arranging information so that your memory has to recall fewer items later.  The most famous example is a plain old US telephone number (indeed, some have speculated that Bell Telephone originally standardized around the seven-digit phone number because of Miller's research).  Here's a little experiment: try and remember the following ten item list:

9 5 4 5 4 8 3 3 0 0

Can you do it? If so, did you find yourself naturally breaking the number down into three pieces like this?

954   548   3300

That's chunking. Instead of memorizing ten distinct items, you automatically grouped the numbers into chunks so that you'd only have to remember three.  Yes, those three items are more complex than the original ten (since you basically have the ten items plus an organizational layer on top of that), but your brain has ways of handling the storage of complex items. The upshot is that we can get around the 7 +/- 2 memory limit by artfully arranging information so that it "appears" to be less than it actually is.  Chunking works best with short lists and relatively simple items, and the effect diminishes rapidly when the viewer is presented with more than five or so items at once.

Chunking is the most effective when all of the items in the list are roughly the same "type" and "size" (e.g. numbers versus words versus phrases). That's where coding comes in.  Simply put, coding is how our brains make things easier to remember by arranging them into groups of like items.  By "like items," I mean practically any grouping that makes the list's elements seem more similar to each other. Groups can be based on virtually any obvious criteria -- for example, something phonetic ("items that start with the letter A" or "words that rhyme") or conceptual ("things that float" or "famous landmarks").  However, the key is that the criteria must be obvious: your viewers most likely won't take the time to guess why you've listed five seemingly-random items in a list, so in general, coding works best with items that are easily and naturally grouped together.

Our brains do chunking and coding automatically as we make our way through the world. However, given how much competition and visual clutter your screen content may face, you might want to take a few steps to make sure the process is as easy as possible. After all, viewers may only be gracing you with a few seconds of their attention, so you need to make that exposure count. Here's how to put chunking and coding into practice:
  • Pre-order items in your list (which should be short and to-the-point!), and group key phrases or concepts into distinct areas on the screen (or specific times in the segment).

  • Repeat key words, phrases or ideas 2-3 times in a row for reinforcement. This not only gives viewers' brains more time to get the idea into short-term memory, but it also primes the viewer to use it as one of the items to encode against.

  • Use oldies-but-goodies like alliteration (words starting with the same letter or sound), rhyme, meter and the "Rule of 3" (building sentences/phrases as a progression of three clauses). Since most viewers have been exposed to these types of codings before, they'll naturally identify the pattern quickly and use it to code against. Remember, time to recognition and comprehension is one of the most critical aspects of any glance medium.

  • Simple is better! No matter how good you get at optimizing your messages to be easily memorable, the simple ones will always be recalled the best. Don't make a five-item list when you only really need to expound on the two or three most important things. As Jason Goldberg noted in a comment on last week's article, a one-item list is hard to beat.
Armed with your newfound knowledge of how to order the messages in your clips, the next step is to think about the context in which your messages are displayed.  That's what we'll talk about next week, along with ways to avoid some common distractions that can draw attention away from your key messages.  If you're tired of all this psychology-oriented stuff, don't worry: we'll be moving along into copy, graphic design and motion before you know it.

Subscribe to the Digital Signage Insider RSS feed


Looking for more articles and research? Our newest articles can always be found at Digital Signage Insider, but there are hundreds of additional research articles in our historical articles archive.


You may also be interested in M2M Insider: our blog about M2M and the Internet of Things.