When you need to think critically, which requires concentration and analysis, multitasking may not be beneficial because it is difficult to give your full attention to more than one task at a time. Critical thinking requires you to think on a number of levels. This is hard to achieve when you are multitasking. For example, if you are taking an exam that is very important you shouldn't be multitasking if you want good results. Critical thinking entails comprehensive, precise and scrupulous thinking that is hard to achieve when you are doing five things at once.
According to William Stixrud, PhD, neuropsychologist, the brain is very much like a computer. You may have several screens open on your desktop but you are only able to think about one at a time. The downside of multitasking is constant distraction and the potential of creating people who do not think clearly or well.
According to Feelgoodzone.com and a book called "The Shallows: How the Internet is Changing the Way We Think, Read and Remember" by Nicholas Carr, the Internet is altering the way that our brains work and may lessen our ability to think critically and focus on certain tasks for sustained periods of time. The Internet may be causing us to think superficially and use a skimming process rather than an in-depth approach to interpret information. Carr notes that certain brain cells are neglected if we don't use focused thinking, and ultimately the pathways will fall apart. When you are subjected to interruptions this reduces your short-term memory and increases your stress level.
Young people are more capable of combining multitasking and critical thinking than older people. The older you get the harder it is to switch back and forth from the original task to another task and then back again. This is due to the natural aging of the brain, according to CNN Health. Both old and young people may give the same amount of attention to a disruptive task during critical thinking, but an older person will have more difficulty reestablishing the neural brain network associated with the critical thinking. Work performance suffers in both young and old people when they are interrupted by another task, but the effects are worse for the older person.
An attorney is a good example of someone who has to think critically and multitask, which can be challenging and demanding. According to Ohiobar.org this is called "continuous partial attention," which takes its toll on critical thinking because the thinking becomes superficial. Attorneys must figure out a way to stay focused while managing to multitask.