The Myth of Multitasking

Many job advertisements ask for candidates who can "multitask," as though doing several things at once were a valuable skill. Research in cognitive psychology suggests otherwise. When people believe they are attending to two demanding tasks simultaneously, they are usually switching rapidly between them, and every switch carries a cost. The mind must drop the rules of one task and reload those of the other, and in that brief interval attention lapses and errors creep in. Studies have found that frequent switchers often take longer to finish a set of tasks than people who complete them one at a time, and they tend to make more mistakes, even though they frequently rate their own performance highly. There are exceptions. A task that has become automatic through long practice, such as walking or folding laundry, can be paired with a conversation with little loss. The trouble arises when both tasks require deliberate thought, like drafting a report while answering a stream of messages. For offices, the implication is not that employees should never be interrupted, but that work requiring concentration deserves protected blocks of time. A worker who appears constantly busy may simply be constantly restarting.