The average person can only keep 7 (plus or minus 2) items in their working memory.
<aside> ℹ️ Miller’s Law is an excellent example of a psychological concept applied to UX. According to this rule, we should organize information in categories no larger than 9, preferably 7. We can apply the Law to any aspect of life involving a relatively complex task.
</aside>
In 1956, George Miller asserted that the span of immediate memory and absolute judgment were both limited to around 7 pieces of information. The main unit of information is the bit, the amount of data necessary to make a choice between two equally likely alternatives. Likewise, 4 bits of information is a decision between 16 binary alternatives (4 successive binary decisions). The point where confusion creates an incorrect judgment is the channel capacity. In other words, the quantity of bits which can be transmitted reliably through a channel, within a certain amount of time.
Dynamic menus, image carousels, and virtual carts all call on the brain’s ability to learn, navigate, and stay on task to achieve an end goal.
Each needless click, clunky moment of navigation or confusing command adds to the cognitive load. The working memory, where our seven (plus or minus two) items are stored and processed, becomes increasingly crowded.
As the brain receives more information than it can handle, its function begins to slow, decision-making is compromised, and at worst tasks may be abandoned.
<aside> 📌 Some level of cognitive load is inevitable for the brain when tackling such tasks. The designer’s job is to predict and accommodate the mind’s working limitations in order to serve the user.
</aside>
Working memory overload can be avoided by steering clear of these main pitfalls:
Common errors include adding huge menus, long lists of items, too many design elements, and large chunks of written content to your site, all of which cause information overload and may increase your bounce rate.
Instead, remove unnecessary elements and tasks, prioritize readability, minimize choices, and avoid confusing icons. This will relieve the cognitive load on users.