By now you must have heard/read numerous people explain the pitfalls of multi-tasking and why its evil.
- Jeff Atwood’s blog on “The Multi-Tasking Myth“
- John Naish’s article on “Is multi-tasking bad for your brain? Experts reveal the hidden perils of juggling too many jobs“
- Clarke Ching’s blog on “Multitasking MAKES YOU STUPID“
- Joel Spolsky’s blog on “Human Task Switches Considered Harmful“
- Gina Trapani’s article on “Work Smart: Stop Multitasking and Start Doing One Thing Really Well“
Some people offer some decent advice on how to avoid Multi-tasking:
- Don’t Multi-task When You Can Use Chunking by F. John Reh
- The Pomodoro Technique forces you to focus on 1 task for 25 mins & then take a short break of 5 mins after every 25 mins (and a long break after 4 Pomodoros).
- The Dangers of Multitasking And How To Stop by Laura Earnest
- How NOT to Multitask – Work Simpler and Saner by Leo Babauta
- How to Avoid Multi Tasking on WikiHow
While I agree with everyone here. There are things in my daily life that contradicts (to some extent) what they are claiming to be universally true for all humans. For Ex:
- I listen to the news on the radio every morning while I brush my teeth
- I have interesting, deep conversations with friends/family while driving on Indian roads (driving itself involves multiple tasks. Driving on Indian roads adds a whole new dimension to it)
- The Indian Gods had attainted a whole new level of multi-tasking
What I’m trying to highlight here is not all multi-tasking is bad/inefficient. If I take the driving example, I can do other tasks while I’m driving. My efficiency starts to go down if I’m driving to new destinations. It further goes down if I’m driving in a different lane-system and a different car.
Its important to note that multi-tasking does not hurt you much if the activities you’re performing are routine activities (embedded in your long-term memory and is referred to as muscle memory.) Multi-tasking becoming significantly exhausting, error-prone and inefficient if the tasks you are performing requires conscious processing/thought (.i.e. uses your prefrontal cortex intensively.) Five brain functions, understanding, deciding, recalling, memorizing and inhibiting thoughts, make up majority of conscious thought. Activities like planning, problem solving, communication, etc use these functions heavily. Hence multi-tasking on such activities is a bad idea.
Harold Pashler come up with a phenomenon called Dual-Task Interference. Via various experiments he showed that performing 2 cognitive tasks at once can reduce the cognitive capacity drastically. But if an individual performed 2 tasks, out of which only one task required conscious processing, then the cognitive capacity did not see the same drop.
There are simple activities which illustrates that one cannot normally carry out two tasks completely independently when each of them requires a choice of response. When we try to do so, substantial delays occur in one or both tasks. This is true even when neither task is anything that would be described as mentally challenging. Much research in this area argues that one particular mental operation is almost invariably carried out sequentially in tasks like this: the planning of responses. The same is true of certain types of decision operations and memory retrievals. On the other hand, the brain seems capable of perceiving stimuli while it is choosing a response, and actually producing motor responses in one task can overlap with the choice of a response in another.
Again, not all tasks requiring a choice of responses are subjected to this sort of processing bottleneck. Tasks that involve extremely “natural” mappings between stimuli and responses appear not to be. For example, repeating words aloud as you hear them is a task most people can carry out in parallel with other tasks (McLeod & Posner, 1984). The same is true of moving your eye to look at a spot (Pashler, Carrier & Hoffman, 1993).
Are humans capable of only uni-tasking? Not at all. If one of the tasks does not involve a choice of responses (e.g., if it merely involves repetitive rhythmic tapping, or requires perceiving and identifying stimuli without the need to decide on responses), interference is often reduced or even absent (subsequent demos on this site will illustrate this point). Laboratory experiments in which response times are analyzed in detail have lent considerable support to the idea of a “central bottleneck” in response planning and indicated that other operations are often processed in parallel between the two tasks (for recent reviews, see H. Pashler, The Psychology of Attention, 1998, MIT Press; P. Jolicoeur, Journal of Experimental Psychology: Human perception and Performance, 1999, 25, 596-616).
Summary: Multi-tasking activities which require conscious processing is exhausting, error-prone and inefficient, hence a bad idea.