On the Myth of Multitasking - Source

My claim that multitasking (as I defined it) is a myth is based on a popular work by a brain scientist. Brain Rules, by John Medina, is a great little book (it now has a companion book about baby brains).

Read all of Medina's chapter 4 (rule number 4: We don't pay attention to boring things) for yourself. But to sum up, let me give a brief quotation from Medina's Brain Rules website page about the rule:

The brain is not capable of multi-tasking. We can talk and breathe, but when it comes to higher level tasks, we just can’t do it.