New research shows that individuals who frequently use more than one screen, have less grey matter in area of the brain, the ACC or anter cingulate cortex (ACC). This ACC is an area of the brain associated with cognition and emotional control.
Researchers from the University of Sussex found that simultaneously using mobile phones, laptops and other media devices could be changing the structure of our brains. And the part of the brain that becomes smaller is involved in processing emotion.
According to the Daily Mail, researchers also found that those who multi-tasked have shortened attention span, were prone to depression and anxiety. People who multi-tasked were not only less efficient but have difficulty paying attention, recalling information and kept changing jobs.
Clifford Nass from Stanford University on multi-tasking
Dr. Earl Miller, Picower Professor of Neurology at MIT on the limits of your brain
The scary prospect is that the findings held, even when differences in personality were taken into account.
The study, published in the journal PLOS ONE, notes that there is a direct link between the size of the ACC and multi tasking. It also note a study done earlier that found multi taskers had less ability to stay focused on activities that needed focus, but another study (Alzahabi, Becker) had contradictory findings: it found that heavier multi taskers were not worse at dual-task performance and were better at task-switching.
According to the Daily Mail, as well as damaging our brains, research by business planning group, Realisation, has found that trying to do too many things at once costs the global economy USD$450 billion annually.