Studies have found that multitasking uses up oxygenated glucose in the brain, taking up whatever energy is reserved and needed to focus on a task.
Explaining how the brain works, Clinical Psychologist Dr. David Rosenstein says we process information in a sort of linear fashion.
He says if you are found switching between tasks your brain is going to sacrifice some of its storage for extra information and will quickly chuck out whatever it has been storing.
Multiple breaks are good. Studying for about 25 minutes,sometimes up to 40 minutes and then taking a break, staying with that topic, coming back to it and continuing is definitely better than just pushing yourself for five hours straight. You are not going to be as efficient. After a couple of hours your capacity for taking information will decrease substantially.— Clinical Psychologist Dr. David Rosenstein