Those who multitask a lot were compared to those who multitask much less.

Here is a link to a longer article that I summarize below:
"Multi-tasking adversely affects brain's learning, UCLA psychologists report"



  In their                                                    multitaskers are

ability to ignore irrelevant information         much worse

ability to organize information                       worse

memory                                                           equal

ability to switch tasks rapidly                         worse        [A surprise! That's what they do a lot and they were worse at it!]

ability to focus on a task                                 worse
                                        

    The research did not find anything multitaskers are better at.

AP. Wednesday, August 26, 2009. Research conducted at Stanford University.
Published in the prestigious Proceedings of the National Academy of Science, August 25, 2009.

What does this mean to you?  It means that if you also do other things while you study, you will not learn as well. Pay full attention to what you are doing (and don't do e-mail or phone or change music every few minutes).