As you probably have noticed, it is never easy to do several things at the same time. The best explanation is that human attentional ability is limited. So doing two tasks or more at the same time necessarily lower the amount of attention one can devote to each individual tasks. This leads to slow processing and errors. Since as we age it becomes increasingly difficult to focus attention on a task, it also becomes more difficult to multitask. Brain training has been shown to improve many abilities: Does it work for multitasking too?
A recent study involving 105 healthy older adults aged 59 to 70 years tested whether it was possible to train the brain to perform a dual task, that is to perform two tasks at the same time.
First, all the participants received one of two versions of a dual task as well as a battery of cognitive tests to assess processing speed, working memory, inhibition, and task switching, which are all necessary to perform two tasks at once. Then the participants attended 1-hour sessions for 5 consecutive days. At the end of the study, both the cognitive battery and the second version of the dual task were administered.
During the 1h sessions, people in the training group practiced performing the dual task task. People in the control group received either a semi-structured internet training or no training at all.
The dual task that was trained included one task presented in the center of the screen and one task presented peripherally. In one version of the dual task, the central task showed numbers appearing one after the other in the center of the screen. The sum of the numbers was then shown and the participants judged whether it was correct or not. In the peripheral task the image of a flower was shown at random locations on the screen and participants “cut” it with the scissor cursor.
In the other version of the dual task, the central task involved letters: Participants judged distances between letters in the alphabet (e.g., H is 3 units away from K). In the peripheral task, the scissors were replaced with a leg and the flower with a soccer ball. Participants “kicked” the soccer ball through a goal.
Why two version of the dual task? When assessing the effect of training one is usually interested in a) whether people get better at the trained task, and b) whether the benefits of the training transfer to a closely related but untrained task. Here the two versions of the dual task allow to assess b), by testing whether being trained with one version of the task improves the performance in the other version of the task.
Results showed that participants did much better at multitasking after training. Interestingly the benefits transferred to the untrained dual task. Brain training can thus be used to get better at multitasking!
The ability to multitask was associated with measures of speed of processing (how fast the brain can process information in general) and to a lesser extend with measures of working memory (the ability to hold information in mind and use it for the task at hand). However, the participants’ general speed of processing and working memory abilities did not improve with training, even though participants got better at performing two tasks at once. This is not a surprising result. Most studies show that brain training is specific. It improves the trained ability as involved in a specific task, but training benefits rarely extend to situations far from the one trained, even though these situations may involve similar skills.
MacKay-Brandt, A. (2011). Training attentional control in older adults. Aging,
Neuropsychology, and Cognition, 18:4, 432-451.