那群吃饭的人中有个年轻的心理学学生，她是俄国人，名叫布卢玛·泽伊加尔尼克（Bluma Zeigarnik），她的导师就是很有影响力的思想家库尔特·勒温（Kurt Lewin）。勒温听说了这个事情后，就思考背后是不是有个更—般的原则。人类记忆是否严格区分已完成的任务和未完成的任务？他们开始观察那些做拼图游戏时被打断的人。他们的研究，以及接下来几十年的很多研究，证实了著名的“蔡氏效应”，（Zegarnik effect）：任务未完成、目标未实现，脑子里就会有个声音不断提醒你去完成任务、实现目标。然而，一旦任务完成了、目标实现了，脑子里的那个声音就会消失。
有个简单办法可以帮助你理解蔡氏效应。随便选一首歌曲播放给自己听，中途关掉，那么这首歌曲就很有可能不时地在你脑中自动播放。如果你把歌曲播放完了，那么大脑就将之“结项”（打个比方啊）。然而，如果你中途关掉，那么大脑就把歌曲看做未完成事务，就像提醒你还有工作要做—样，大脑会不断在你的思维流里插人歌曲片段。就是因为这个原因，演员比尔·默里（Bill Murray）在电影《士拨鼠日》（Groundhog Day）中不断关掉收音机闹钟的铃声—《你是我的，宝贝》，这首歌曲不断在他脑中播放（不断把他逼疯）。就是因为这个原因,这种“耳朵虫”往往令人讨厌而非愉悦。我们更可能在中途关掉讨厌的歌曲，所以萦绕在我们脑中的多是讨厌的歌曲。
Bluma Zeigarnik with her husband Albert Zeigarnik before arriving in Berlin.
The picture was taken in Kovno (now Kaunas), Lithuania, in 1919-1920.
The Zeigarnik Effect
The discovery began, according to the legend among psychologists, with a lunch in the mid-1920s near the University of Berlin. A large group from the university went to a restaurant and placed their orders with a single waiter, who didn’t bother writing anything down. He simply nodded. Yet he served everyone’s food correctly, a feat of memory that impressed the group. They finished eating and left the restaurant, whereupon one person (the legend is unclear on exactly who) returned to retrieve an item that had been left behind. The person spotted the waiter and asked for help, hoping to benefit from his obviously excellent memory.
But the waiter looked back blankly. He had no idea who the patron was, much less where the person had sat. When asked how he could have forgotten everything so quickly, the water explained that he remembered each order only until it was served.
One of the scholars, a young Russian psychology student named Bluma Zeigarnik, and her mentor, the influential thinker Kurt Lewin, pondered this experience and wondered if it pointed to a more general principle. Did the human memory make a strong distinction between finished and unfinished tasks? They began observing people who were interrupted while doing jigsaw puzzles. This research, and many studies in the following decades, confirmed what became known as the Zeigarnik effect: Uncompleted tasks and unmet goals tend to pop into one’s mind. Once the task is completed and the goal reached, however, this stream of reminders comes to a stop.
A good way to appreciate the Zeigarnik effect is to listen to a randomly chosen song and shut it off halfway through. The song is then likely to run through your mind on its own, at odd intervals. If you get to the end of the song, the mind checks it off, so to speak. If you stop it in the middle, however, the mind treats the song as unfinished business. As if to keep reminding you that there is a job to be done, the mind keeps inserting bits of the song into your stream of thought. That’s why when Bill Murray in Groundhog Day keeps shutting off “I Got You Babe” on his clock radio, the tune keeps going through our minds (and keeps driving him crazy). And that’s why this kind of ear worm is so often an awful tune rather than a pleasant one. We’re more likely to turn off the bad one in midsong, so it’s the one that returns to haunt us.
Why would the mind inflict “I Got You Babe” on itself? Psychologists have generally assumed that earworms are an unfortunate byproduct of an otherwise useful function: the completion of tasks. How the Zeigarnik effect works has been explained by various theories over the years, including two rival hypotheses that dominated the debate. One hypothesis was that the unconscious mind is keeping track of your goals and working to make sure they’re accomplished, so these stray conscious thoughts are actually a reassuring sign that your unconscious will stay on the case until the job is done. The rival hypothesis was that the unconscious mind is seeking help from the conscious mind: Like a small child tugging at the sleeve of an adult to get attention and help, the unconscious mind is telling the conscious mind to finish the task.
But now there’s a newer and better explanation for the Zeigarnik effect, thanks to some recent experiments conducted by E. J. Masicampo, a graduate student at Florida State working with Baumeister. In one study, he assigned some students to think about their most important final examination. Others, in a control condition, thought about the most important party pending on their social calendar. Among the ones who thought about the exam, half were also told to make specific plans of what, where, and when they would study. But nobody did any actual studying during the experiment.
Then everyone performed a task that contained a subtle measure of the Zeigarnik effect. They were given word fragments and instructed to complete them. The fragments were artfully constructed so that they could be completed with words relevant to studying—but also with alternative, irrelevant words. For instance, the item re_ _ could be completed as read but also be made into real, rest, reap, and reek. Likewise, ex_ _ could be completed as exam but also as exit. If thoughts of the unfulfilled task of studying for the exam were on the person’s mind, he or she would be expected to generate more exam-related words due to the Zeigarnik effect. And indeed, Masicampo found that these words popped more often into the minds of some people: the ones who had been reminded of the exam but hadn’t made plans to study for it. But no such effect was observed among the students who’d made a study plan. Even though they, too, had been reminded of the exam, their minds had apparently been cleared by the act of writing down a plan.
In another experiment, participants were asked to reflect on important projects in their lives. Some were told to write about some tasks they had recently completed. Others were told to write about tasks that were unfulfilled and needed to be done soon. A third group was also told to write about unfulfilled tasks, but also to make specific plans for how they would get these done. Then everyone went on to what they were told was a separate and unrelated experiment. They were assigned to read the first ten pages of a novel. As they read, they were checked periodically to ascertain whether their minds were wandering from the novel. Afterward, they were asked how well they had focused and where, if anywhere, their minds had wandered. They also were tested on how well they understood what they’d read.
Once again, making a plan made a difference. Those who’d written about unfulfilled tasks had more trouble keeping their minds focused on the novel—unless they’d made a specific plan to complete the task, in which case they reported relatively little mind wandering and scored quite well on the reading comprehension test. Even though they hadn’t finished the task or made any palpable progress, the simple act of making a plan had cleared their minds and eliminated the Zeigarnik effect. But the Zeigarnik effect remained for the students without a plan. Their thoughts wandered from the novel to their undone tasks, and afterward they scored worse on the comprehension test.
So it turns out that the Zeigarnik effect is not, as was assumed for decades, a reminder that continues unabated until the task gets done. The persistence of distracting thoughts is not an indication that the unconscious is working to finish the task. Nor is it the unconscious nagging the conscious mind to finish the task right away. Instead, the unconscious is asking the conscious mind to make a plan. The unconscious mind apparently can’t do this on its own, so it nags the conscious mind to make a plan with specifics like time, place, and opportunity. Once the plan is formed, the unconscious can stop nagging the conscious mind with reminders.
That’s how Allen’s system deals with the problem that he calls monkey mind. If, like his typical client, you’ve got at least 150 items on your to-do list, the Zeigarnik effect could leave you leaping from task to task, and it won’t be sedated by vague good intentions. If you’ve got a memo that has to be read before a meeting Thursday morning, the unconscious wants to know exactly what needs to be done next, and under what circumstances. But once you make that plan—once you put the meeting memo in the tickler file for Wednesday, once you specify the very next action to be taken on the project—you can relax. You don’t have to finish the job right away. You’ve still got 150 things on the to-do list, but for the moment the monkey is still, and the water is calm.www.psychspace.com心理学空间网