Month: October 2016

Multitasking Is Inefficient, Ineffective and Bad For Your Brain!


Many people boast about their ability to multitask, but it’s really nothing to brag about.  The simple truth is that it’s inefficient, ineffective and the human brain is not built for it.  If you’re multitasking you’re not going to be able to produce your best work.  This is why many states have implemented laws such as not allowing drivers to text.

Studies show that you’re not doing your brain any favors either.  The brain produces dopamine when we successfully complete a task.  Our brain loves these quick little dopamine hits when answering an email or text and crave even more, resulting in even more multitasking.  Another down side is that multitasking also increases the production of a stress hormone called cortisol and this tires us.  Beyond the chemical implications, our brains were designed to focus on one thing at a time and when we barrage them with information it only slows them down and produces less than quality results.

A University of London study showed that people experienced a significant drop in IQ level when multitasking.  Even context switching, which is a less rapid switching of focus, costs us in efficiency and effectiveness.  In fact, interrupting your focus to read an email has been shown to reduce your effective IQ by 10 points.

Gerald Weinberg, computer scientist and psychologist, has assessed that context switching between projects costs you 20% of your time per project.  This means if you are switching back and forth between two projects for the week then you will effectively have only 40% of your overall time to devote to each project due to the cost related to switching context (see the graph below from Gerald Weinberg).


With all the distractions technology has introduced in society and the workplace, it’s a wonder that we can get very much done at all.  We have emails, texts, tweets, alerts and social media to name a few. To address the situation, try to commit to specific blocks of time to address these and minimize interruptions.  Work emergencies will occur and interrupt our work efforts also.  It will help to derive a criterion with your customers for the definition of an emergency and effectively triage incidents.  Whenever possible we want to have people assigned to one project/task at a time, let them get it done and then move onto the next one.

The bottom line is that multitasking is not something to add to your list of skills, but instead something you want to minimize.

Try the exercise below to illustrate the loss of time due to context switching.


Label three columns on a sheet of paper as follows (“1-10”, “A-J”, “I-X” [the roman numerals]).  Now time yourself on how long it takes you to first write the numbers 1-10 individually under the column labelled “1-10” then writing the individual letters A through J under the “A-J” column and then writing the Roman numerals I through X under the “I-X” column.

Now time yourself for this second way of writing down the letters and numbers.  Get a fresh piece of paper and put the same three columns on the top again.  Now, first write “1” in the “1-10” column and then go to the next column and write “A” and then the next column and write “I” and then return to first column and write “2” and so on, writing each next number or letter in the next column until all of them are written down.

Your time in writing them the second time is substantially longer than it took the first time.  Why is this?  Because switching focus costs you time.