Research published in Proceedings of the National Academy of Sciences shows the brains of older people when interrupted tend to have greater difficulty switching back to their original task than younger people.
Participants were given a memory task which was interrupted with another task. They were then asked to return to the original activity.
Both older and younger people directed about the same amount of attention to the interrupting task. However, MRI scans show that older adults ran into more trouble when they needed to let go of the interruption and re-establish the neural network associated with the original memory.
Researchers also found that brain changes involved in multitasking may begin as early as the 20s and 30s.