You may be reading this while on a conference call, pushing your child on a swing – or both. But is multitasking really a good idea, or does it make us do everything more slowly and less well than if we were concentrating on one task at a time?

The solution

Psychologists cite robust research that paying more attention to a task improves performance. Humans, they argue, are good at doing rapidly sequential tasks, rather than simultaneous ones. My teenagers insist it is fine to revise while texting and watching YouTube – but they are wrong. In 2009, a research team from Stanford, led by Clifford Nass, compared heavy versus light media multitaskers in a series of tests. Nass thought the heavier multitaskers would be better at organising and storing information and have superior memories, but it turned out that the opposite was true. When the groups were shown configurations of coloured shapes and asked to remember their positions and ignore others, the multitaskers couldn’t do it. They were constantly distracted and their ability to switch between tasks, filter irrelevant information and remember what they had seen was worse than the lighter multitaskers.

A team led by David Strayer at the University of Utah looked at people who drive while using the phone and found that they were more than twice as likely to miss stop signs. In a later study, Strayer found that people who are most likely to multitask are those who think they are great at it. Seventy per cent of the 310 students in his study thought they were above average at multitasking. People who multitasked the most had high levels of impulsive behaviour and were generally the most ill-suited to attempt more than one job at a time.

Using a mobile, even hands-free, while driving delays the amount of time needed to brake in an emergency and halves the information that drivers are aware of. But Strayer found that people consistently overestimated how good they were at driving while on the phone.

Nass’s research led him to suggest that we should spend 20 minutes on one task and then switch to another, rather than flitting any faster between the two. Tests that measure the ability to remember shapes are less compelling than real-life multitasking research, but the evidence suggests that we delude ourselves if we think we can do more than one thing well at the same time. Limited research suggests that women may be a teeny bit better at it, but few of us are naturals. Strayer’s research suggests that around 3% of the population are “supertaskers” who do better the more they do. The rest of us, however, should stick to one thing at a time.