In discussing how magicians manipulate attention (looking at the way Apollo Robbins the Gentleman Thief picks pockets) they described a technique called time misdirection. This is when your attention is misdirected in the time dimension. Magicians may introduce delays between the method behind a trick and the effect itself, which makes it difficult to link the two (see pg. 69).
Here's an example from the book:
Imagine that a magician fakes a coin transfer from his left to his right hand, and then opens his right hand to reveal that it is empty. Because there is no separation between the sleight (the fake transfer) and the magical effect (the vanished coin), you may easily conclude that the coin was never actually transferred but remained concealed in the magician's left hand. A more accomplished magician will introduce a separation -- a parenthesis of forgetfulness -- between the method and the effect. For example, after the fake coin transfer, and before revealing his empty right hand, he may reach into his pocket for the overt purpose of retrieving a magic wand, but in fact he is also dropping the palmed coin inside his pocket. Then, touching the magic wand in his left hand to his right hand, he shows that the coin has disappeared.You can also see the master of sleight, Slydini, using time misdirection over & over in this routine on the Dick Cavett show:
Parenthesis of ForgetfulnessA primary skill of magic is to learn how to hide information. In this case, magicians use the delay of time to take advantage of the way our brains work and misdirect you from the method to the effect. However, when we are designing interfaces this parenthesis of forgetfulness can work against us (often the things that magicians employ, designers have to avoid).
When designing an experience we need to keep the result as close to the action as possible. In other words we have to shorten the parenthesis of forgetfulness.
Performance delays can create this parenthesis. Let's say you want to withdraw or send funds on your bank's web site. If you withdraw funds but it takes a while to show your balance updated in context on the page then your brain will have to work harder to causally tie the action and the result together. One solution is to keep refreshing the user's memory of the relationship by such methods as progress indicators while the user is waiting for the result.
Taking the user out of context through a page refresh to show the result of an action will also create this parenthesis. The time it takes to get to the result (the new page) as well as the change blindness that results from the refresh zaps the brain and takes it to the zone of forgetfulness. A solution to this is to draw the user's attention to what just happened. For example, highlighting the change will work as it refreshes the user's memory and ties the action and result together. But the best solution is to not have action & result span a page refresh. This will remove the parenthesis altogether. Elsewhere I have written about this disconnect before, especially as it relates to change blindness.
What examples of the parenthesis of forgetfulness have you seen in web & mobile experiences? What solutions have you found for these situations?