why multitasking doesn't work

 Jennifer Morris, MD MBA

ABPN, ABOM, ABPM-add, ABSSP

Multi-tasking...heralded as an efficiency  moniker for high functioning individuals. but is it? 

Multi-tasking is defined as tackling more than one task at a time...it sounds efficient, and a great use of time. In fact, 75% of employees feel the pressure to multitask;  multi-tasking in meetings is common, as is checking email while on the phone.  Multi-tasking has been amplified by remote work.  However, in reality, your brain is not tackling two tasks at the same time. The human brain just doesn't work that way. 

 The cognitive and neural constructs of the human brain preclude multi-tasking. This has been demonstrated in functional neuroimaging studies on the brain regions/systems involved in executive control and sustained attention, including the frontoparietal control network, the dorsal attention network, and the ventral attention network (Madore.) Instead, what occurs is rapid task-switching...back and forth between two or more competing items. 

 Constant switching taxes the brain- it derails efficiency and tires the mind out. Focus is especially impacted, even after the multi-tasking is concluded.  In addition,  task-switching requires additional "brain resources" to accomplish the switch (Madore.)  The brain requires supplemental neural recruiting to process bringing to mind the new task and to reallocate attention and focus to the "new" information. Automaticity and efficiency are lost. Neuroimaging also notes that aging does not develop the skillset of multi-tasking; rather, the opposite is true. Older adults have diminished multitasking abilities due to reduced connectivity between brain networks of attention, control and memory. 

Multi-tasking decreases productivity by as much as 40 percent. Mental overload can result in catastrophe, with fatigue and burnout risks. There is a mental cost to adjust mental control to the new task, and to competition of carry-over of the previous task. It also takes time to recall where you are on a previous task, and when/how to switch tasks. This was demonstrated in "switch" experiments, where individuals performed a series of tasks with and without switching while performance time was measured;  the time to complete these tasks telescoped with switching. (apa)  

In summary, multi-tasking is a misnomer. Those who attempt to multi-task are actually engaged in rapid task switching. This rapid task-switching has a cognitive cost, and may ultimately lead to fatigue and burnout. A better strategy is to allocate time to each individual task, slating other tasks for other times. Strategies to avoid distraction or subconscious multi-tasking include making a list of pending items, prioritizing those things that need to be completed first (not simultaneously) and removing distractions (phones, email) when working on critical tasks. 

1. Miller Earl. Picower Professor of Neuroscience, MIT. 

2. Madore, Kevin, Anthony Wagner. Multicosts of Multitasking. Cerebrum, 2019, march-april. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7075496/. Accessed 9/24/24. 

3. Multitasking: switching costs. American Psychological Association; March 20, 2006.  https://www.apa.org/topics/research/multitasking. Accessed 9/24/24.