So last week, I linked back to an article I’d written some time ago about cognitive load — basically, the idea that ‘making the end user work for it’ was a bad idea. You want your website to be as easy to understand as possible, which in general means you want to make it as simple as it can be while still accomplishing its goal. One of my employees came up with a question that stumped me: “Jared,” he said, “If cognitive load is bad, why does everyone seem to learn better through videos with moving pictures and sound more than static pictures or text alone?”
I’ve been dwelling on that for a bit, and decided to do a little research — and what I came with, amazingly, fed right back into the basic precepts of web design. There are a lot of theories about cognitive load and its effects on communication (including the ‘communication’ that takes place between a computer and a user that is surfing) — a deeeep rabbit hole awaits anyone who gets into this. So I’m very much skimming and summarizing here, but it’s nonetheless an important lesson for web developers.
Sometimes, More is More
The first thing to understand about the relationship between web design and cognitive load is that the human brain has serious problems doing several things at once. For a brief time around the turn of the century, ‘multitasking’ was the buzzword, and everyone wanted employees who could do more in the same limited timespan because they were ‘effective multitaskers.’
Then, a series of damning studies came out that showed that humans absolutely suck at multitasking. Having an electronic device that was capable of delivering messages, playing games, or providing other distractions merely in sight while you were working caused an effective IQ decrease equivalent to being drunk. You didn’t even have to actually multitask to suffer — the fact that you thought about multitasking was enough.
That led web designers circa late 2010 to suddenly try to reduce the number of things they were demanding of their visitors, because the sight of that link to the FAQ might be distracting them from the introductory video!
Other Times, More Is Less
What many laypeople missed out on, however, is the subtle difference between definitions of ‘multitasking.’ Because humans virtually never actually do multiple things at once in purely manual terms, unless one or both of them are purely automatic (like clicking a mouse while taking a bite of a banana — that bite requires absolutely zero attention, so it doesn’t count.) Instead, what we do is rapidly switch back and forth between tasks. You’re coding, and your phone rings, so you stop and talk, and then go back to coding, and then an email arrives, so you stop and answer it, and then go back to coding…and that effect is what the anti-multitasking studies of the past five years have been on about.
But what we humans to exceedingly well is one thing at a time — even if that one thing could reasonably be broken down into tasks that, out of context, seem several times as difficult as, say, typing with one hand and eating a banana with the other.
Consider, for example, the number of different actions needed to play a standard electric guitar. You’ve got one hand working the frets, one hand contorting itself to pluck some strings but not others (and occasionally whipping out to slap the whammy bar), your foot on the wah pedal, and quite possibly a microphone to keep in front of because you’re quite possibly singing at the same time. Taken individually, these tasks aren’t hugely difficult, but compared to clicking and nomming a mouth-hole-shaped fruit, they sure are. But the human brain treats it all as one task — ‘playing the guitar’ — and stores all of it as a unit.
But there’s more! In many instances, the human brain not only doesn’t suck at multitasking, it actually performs significantly better at some tasks when there are more facets involved in the processing and execution. For example, if you’re an avid player of the game League of Legends and you regularly play with the sounds on, turning them off will be an exceedingly different and altogether more challenging experience. When you can’t hear the special abilities of other players go off, you lose an incredible amount of information about which of your options are appropriate.
Because the ‘multitasking’ you’re doing is happening in different areas of your brain (visual processing, audio processing, strategic planning, reflexive responses, muscle memory), the cognitive load is actually reduced by the increased level of input. Essentially, you’re roping in more of your brain to help on the task, so the load-per-neuron is reduced.
How All This Affects Web Design
Wow, that was a long road to travel to bring this back to web design — but hopefully, worthwhile. This gets back to web design in the form of several key lessons:
- Overloading a user with options increases cognitive load, because they have to decide which option is relevant and effective.
- Overloading a user with unusual stimulus increases cognitive load, because the brain has to essentially ‘translate’ from the unusual to the usual in order to grasp information. This is why most blog posts are a thousand times easier to read than most formal scientific studies or Master’s thesis.
- Overloading a user with stimulus in any one area (a lot of disparate visual elements, multiple levels and kinds of audio, a chaotic jumble of text) increases cognitive load, because the user has to sort through the stimulus and decide which of each type is worth paying attention to and which can be ignored.
- Overloading a user with interruptions increases cognitive load most of all, because it turns using your website into the wrong kind of multitasking — the IQ-reducing kind. (This is why we don’t use popups, content-blocking overlays, and other similar disruptive elements, mmkay?)
- When you use different kinds of stimulus (i.e. text, graphical, audial, etc.) to provide the user with information about what they’re doing (mouseovers causing an icon to shade, small but relevant noises when the user clicks, hovers over, or otherwise interacts with an important element, and so on), you enhance their ability to comprehend their own actions, which reduces the cognitive load.
- When you use stimulus to identify a task, any user who has previous experience with that task will immediately engage that task’s ‘rules’ and ‘procedures,’ and their cognitive load drops because they know already what to do under what circumstances. This is often seen when a user hits a ‘username/password’ box, for example. It can also be engaged deliberately by using similar stimuli to surround similar tasks across your site, so that a user who has used your FAQ will have an instinctive understanding of how to use your e-commerce checkout interface.
- When you use stimulus that works together to form a single message — say, a multimedia presentation with a talking head, incoming audio, and pop-up captions — you have to expect that a user won’t do anything else while that message is on the screen, because all of their processing centers are busy. But you can be much more assured that the message will sink in and get properly sorted into long-term memory. This is precisely why instructional/introductory videos are so effective.
In those last three points, you’re quite effectively increasing the total stimulus of the user, but you’re decreasing their cognitive load at the same time — so we’re back to the promise of the title: done properly, more really can be less when it comes to multimedia and web design. Whew!