In the year 2000, two American researchers (Kathleen D. Vohs and Todd F. Heatherton), performed a Consumer Behavior “torturous study;” they asked a group of participants to watch a boring movie for about an hour. To add onto the torture, they placed a table with snacks in the room – different kinds of chocolate, chocolate cake, chips and more.
The participants were divided into two groups in two separate rooms. One group had the snacks on the table beside them. The other group had the snacks on a table on the other side of the room, so those who wished to have a snack would actually have to get up.

• Before the study, the participants were asked to answer a general questionnaire. One of the questions was whether the participants were watching their weight/dieting.
• The participants probably assumed that they were going to be asked some question about the boring movie later, not suspecting that a key part of the study has to do with the snacks!

After they were done watching the movie, “the torture” continued – the participants were asked to individually solve a geometric puzzle that in fact was not solvable. The researchers monitored the amount of time it took each one of the participants to give up and stop trying to solve the puzzle.
The results were stunning – among the dieters, the group of participants that sat near the snacks gave up on solving the puzzle much faster than the group that was in the room in which they had to get up and walk to the snacks on the other side of the room.

Why did that happen?

The dieters who sat right by the snacks had to employ large amounts of mental power to avoid munching on the snacks. The dieters who sat far away from the snacks, were not in constant eye contact with them, so it was easier for them to resist the temptation and they didn’t have to employ as much “self-regulation.” Among the participants who were not dieting, no difference was found between the groups who sat near the snacks and those who sat far away, apparently since non-dieters did not put significant thought and effort into the snacks.

So, as the theory suggests, when the participants reached the second stage, in which they had to solve the unsolvable puzzle, the dieters from the first group – those who were sitting near the snacks – were mentally exhausted from their efforts to not eat the snacks, and they gave up faster on the puzzle.

Additional studies support the theory that we have a ‘mental power bank’ – our self-control and self-discipline are resources that can get temporarily depleted. On a few additional studies by the same researchers and others, other elements that cause “mental depletion” were tested. Among the things that were found to temporarily deplete our mental resources were: keeping up with hard endurance training, staying alert at a lecture, trying to navigate to an unfamiliar address, and making choices.

For many of us, some of these activities seem obvious – we can feel that decision-making is very mentally consuming – can you recall a time in which you went shopping and felt completely exhausted afterwards? You have to constantly browse and make small decisions between different products, so it is natural to feel depleted afterwards.
While most people can easily see how some activities can be “mentally tiring,” many are not aware of the fact that we have “one mental bank”. What I mean to say is, if you’re going shopping and have to make a handful of minor decisions, it might affect your ability to write a paper for school or prepare a report right after.

Is this knowledge actionable?

On an individual level, it sure is, and once you start thinking of your mental energy as a resource you can engage in better resource management. For example, if you’re going for a job interview or a meeting somewhere you have not been to before, trying to find your way there for the first time right before the meeting may not be the wisest thing to do. If it is very important that you be at your best, you might consider finding the place a day earlier.

On a B2C marketing level, it is important to take into account the implication of mental depletion on your customers. For example, the presence of many options (say the same sofa in many colors) can be overwhelming. The effect of that can cause the customer to give up altogether; or, on other occasions, be less resistant to a salesperson’s pitch. So, like most research findings, the results can go more than one way – analyze the characteristics of your business and your sales funnel to see how you should adjust to the issue of mental depletion.