The people who multitask the most are the ones who are worst at it. That's the surprising conclusion of researchers at Stanford University, who found multitaskers are more easily distracted and less able to ignore irrelevant information than people who do less multitasking.

    "The huge finding is, the more media people use the worse they are at using any media. We were totally shocked," Clifford Nass, a professor at Stanford's communications department, said in a telephone interview.

    The researchers studied 262 college undergraduates, dividing them into high and low multitasking groups and comparing such things as memory, ability to switch from one task to another and being able to focus on a task. Their findings are reported in Tuesday's edition of Proceedings of the National Academy of Sciences.

    When it came to such essential abilities, people who did a lot of multitasking didn't score as well as others, Nass said.

    Still to be answered is why the folks who are worst at multitasking are the ones doing it the most.

    It's sort of a chicken-or-egg question.

    "Is multitasking causing them to be lousy at multitasking, or is their lousiness at multitasking causing them to be multitaskers?" Nass wondered. "Is it born or learned?"

    In a society that seems to encourage more and more multitasking, the findings have social implications, Nass observed. Multitasking is already blamed for car crashes as several states restrict the use of cell phones while driving. Lawyers or advertisers can try to use irrelevant information to distract and refocus people to influence their decisions.

    In the study, the researchers first had to figure out who are the heavy and light multitaskers. They gave the students a form listing a variety of media such as print, television, computer-based video, music, computer games, telephone voice or text, and so forth.

    斯坦福大學研究者得出一個令人吃驚的結(jié)論：那些負有多重任務的人往往干不好工作，因為他們更容易分心，和擔負工作少的人相比，更不易識別被不相關(guān)的信息。

    斯坦福大學交流與傳播系的教授，克利福德·納斯在一次電話訪談中說，"研究發(fā)現(xiàn)，人們用的媒介越多，就越不容易用好。這使我們非常震驚。"

    研究者調(diào)查了262位大學生，把他們分為高、低多任務小組，在記憶力、從一個任務到另外一個任務的切換能力和對任務的關(guān)注力上進行比較。其研究結(jié)果發(fā)表在本周二出版的美國國家科學院學報上。

    當涉及到這些關(guān)鍵能力時，擔任多重任務的人得分沒有其他人高，納斯如是說。

    仍待解決的問題是，為什么那些干多重任務差的人是干得任務最多的？

    這似乎是"先有雞還是先有蛋"的問題。

    "是多重任務導致他們表現(xiàn)糟糕，還是他們的糟糕表現(xiàn)使他們成為多重任務者？"納斯考慮道，"這是先天的還是后天的？"

    納斯注意到，在這個似乎鼓勵做多重任務的社會環(huán)境下，此項發(fā)現(xiàn)具有社會影響。車禍已歸咎于多重任務，好幾個州限制開車時使用手機。律師或廣告商可以使用無關(guān)信息來分散注意力，并重新關(guān)注人們影響他們的決定。

    在這項研究中，研究者首先要弄清楚多重任務的輕重之分。他們提交給大學生一個表格，列有一連串的媒介，如印刷、電視、電腦各種媒體的視頻，音樂，電腦游戲、電話語音或文字，等等。