Why you should design user experiences with the human brain in mind

I find it fascinating when designers discuss how a certain solution could be more “intuitive” for the user. I have heard arguments of all kinds supporting the idea of a user flow becoming “easier” or “more difficult”.

As much as we designers would like to believe we know what “easy” or “difficult” means to our users, the truth is, most of the time, we’re not the user we’re designing around.

Luckily for us, the users we design for have something in common, a brain. Also, fortunately, our users operate their brain while using the products we design.

But we try to bring some truth into our process, so we use tools, such as personas. Personas are fictitious representations of the target user that summarises its most relevant attributes.

Nancy (one of my favourites), is one of our personas here. So now we can discuss what Nancy likes, what she understands, and what frustrates her. But, let’s be honest, most of the time Nancy’s attributes are not specified through any structured user research. Yes, it would be ideal to conduct user-research, but many times we do not have the time or resources to do it.

The processes we follow (and we can be as agile as we want) in our projects aren’t flexible enough to re-evaluate and assess Nancy’s preferences as much as we should.

Therefore, continue using personas, and continue using the good practices that the big technology companies define (because they are the ones with the time and resources to do so). However, there is something else we can do… Use the brain!

I know, right? If we all have a brain, and we all use it when interacting, we could just identify it’s patterns and exploit them through design… Eureka!

Well, fortunately quite some smart people focused their lives on studying the human brain, and they drew some conclusions that we, UX designers, can use when designing interactions.

Note: Just in case you did not know, the human brain is an extremely complex piece of meat. Actually, we are still scratching the surface and we are far from understanding all its complexity.

In order to start applying these principles, it is important to get familiar with one term: cognitive load.

Cognitive load for people that did not study psychology and are not planning to

In simple words, cognitive load is the total amount of mental effort that is required to complete a task (considering also the processing of information).

Let’s try to get through this principle without overloading our cognitive capabilities:

Nancy uses a web product for work on a daily basis. This product provides information to her in various manners: sometimes through written text, sometimes audio, and sometimes a video that combines audio, motion, and subtitles (yes, Nancy has quite an amazing job).

Nancy’s sensory memory filters out most of these inputs, but keeps an impression of the most important items long enough for them to pass into working memory.

Well, at this point it is important to highlight that we, humans, suck when it comes to working memory . Our working memory can generally hold between five and nine items of information at any one time. Therefore it is really important for us, designers to be really careful when we are defining the Information Architecture (IA) of our products.

Apart of being quite limited, Nancy’s working memory processes the information inputs separately. Visual and auditory information are processed separately by two different channels. Therefore, be meticulous when defining the format in which the information will be provided, since you can overload the cognitive capabilities of your user.

Luckily for Nancy, her long-term memory rocks and compensates the deficiencies of her working memory. When Nancy’s brain processes information, it is categorised and moved to the long term memory, where it is stored in knowledge structures. These structures are called schemas. And basically, schemas are amazing because they organise the information according to how Nancy is going to use it.

Well, I think we got enough for one session. The next time you are designing just remember, your user has a brain that works in a certain manner, try to use this in your advantage:

• Choose wisely the format you use to provide information. Consider that visual and sound inputs are processed by different layers.
• Make sure you do not overload Nancy’s working memory with too much stuff (let’s try to limit it to seven items).
• Make sure that your design makes use of Nancy’s schemas in order to reduce the amount of rehearsing to encode information.
• Consider predictability in your design. If Nancy expects to find something somewhere, it might be wise to actually place it there. Otherwise you would require her to re-organise information and consequently use more working memory and increase the chances to overload her.