直覺或能反映可靠記憶

美研究發現：直覺或能反映可靠記憶

曾翌　科技日報 發布時間：2009-2-23 14:42:19
來源：http://www.sciencenet.cn/htmlnews/2009/2/216517.html

直覺也許反映了可靠記憶（圖片來自網絡）

曾幾何時，人們一直把直覺，也就是所謂“第六感”帶來的成功視為“僥幸”，但是人們也許不知道：直覺也許反映了可靠記憶。

“埃文斯頓，病了”——這是你能感覺到的，你確定你能下結論，但這僅僅是一種“僥幸猜中”。但是來自美國西北大學的一項新研究提供了準確的電生理學證據，證明以上結論有時並不隻是猜測。

這項研究利用最新的“讀腦”技術研究那些不能有意識獲取的記憶的驚人準確性。在一項特殊的識別測試中，猜測跟調查參加者有意識記住的一樣或者更準確。“即使在日常情況下，我們也可能知曉的比我們想象得多。”西北大學心理學教授肯·帕勒說，潛意識記憶發揮著作用，例如，識記罪犯和考試正確答案，或者在一大堆消費品中選擇是由在潛意識層麵非常活躍的記憶決定的。

這項研究把“僥幸猜中”同可靠記憶聯係起來，建議人們要接受多種類型的知識。

在記憶測試的第一階段，參與者們會在電腦屏幕上看到許多繽紛變幻的圖案。參與者們嚐試著全神貫注記住一半圖案。他們在看圖片的時候，會聽到一些號碼，例如3、8、4，他們必須記住這些號碼並且判斷其奇偶，然後回答下一題。每一題都會聽到一個新數字，他們需要按鍵完成奇偶判斷任務。也就是說，他們在試圖記住一半圖案的同時，被另外的任務極大地分心。

一會兒之後，他們觀看一組組相似的圖案來進行識記測試。“很明顯的，參與者們能更準確的挑選出老圖案，但觀看這些老圖案時是分心的而非全神貫注的。”帕勒說。“同樣的，如果叫他們猜，他們會更準確。”

在記憶力測試中，分散注意力通常使記憶不佳。“但是我們研究結果顯示，即使注意力被分散，視覺係統仍能很好的儲存信息。”帕勒說。

當隱性識記發生時，腦波明顯不同於有意識識記時的腦波。當參與者看到一幅老圖片時，一種獨特的隱性識記信號就被觀測到。

這項發現包括記憶效應和腦波效應。“這種獨特的結果表明，當人們記憶時，他們能比他們以為的知道更多。”帕勒說。

這項研究基於一項認為健忘症患者擁有強大的隱性記憶的研究。

研究人員建議不應該隻依賴於有意識的記憶，帕勒總結說：“我們也必須培養自己的直覺天性和創造性。直覺也許一直對於解決生活中各種問題扮演著至關重要的角色，甚至包括一些大問題，如經濟危機的解決方案。”

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That Gut Feeling May Actually Reflect a Reliable Memory

February 10, 2009 
來源：http://www.northwestern.edu/newscenter/stories/2009/02/paller.html


EVANSTON, Ill. --- You know the feeling. You make a decision you’re certain is merely a “lucky guess.”

A new study from Northwestern University offers precise electrophysiological evidence that such decisions may sometimes not be guesswork after all.

The research utilizes the latest brain-reading technology to point to the surprising accuracy of memories that can’t be consciously accessed.

During a special recognition test, guesses turned out to be as accurate or more accurate than when study participants thought they consciously remembered.

“We may actually know more than we think we know in everyday situations, too,” said Ken Paller, professor of psychology at Northwestern in the Weinberg College of Arts and Sciences. “Unconscious memory may come into play, for example, in recognizing the face of a perpetrator of a crime or the correct answer on a test. Or the choice from a horde of consumer products may be driven by memories that are quite alive on an unconscious level.”

The study links lucky guesses to valid memories and suggests that people need to be more receptive to multiple types of knowledge, Paller said.

Paller and Joel L. Voss, who received his Ph.D. at Northwestern and is now at the Beckman Institute, are co-investigators of the study. “An Electrophysiological Signature of Unconscious Recognition Memory” will be published online Feb. 8 by the journal Nature Neuroscience.

During the first part of the memory test, study participants were shown a series of colorful kaleidoscope images that flashed on a computer screen. Half of the images were viewed with full attention as participants tried to memorize them.

While viewing each of the other images, they heard a spoken number, such as 3, 8 or 4, which they had to keep in mind until the next trial, when they indicated whether it was odd or even. On every trial they had to listen to a new number and press a button to complete the number task.

In other words, they could focus on memorizing half of the images but were greatly distracted from memorizing the others.

A short time later, they viewed pairs of similar kaleidoscope images in a recognition test.

“Remarkably, people were more accurate in selecting the old image when they had been distracted than when they had paid full attention,” Paller said. “They also were more accurate when they claimed to be guessing than when they registered some familiarity for the image.”

Splitting attention during a memory test usually makes memory worse. “But our research showed that even when people weren’t paying as much attention, their visual system was storing information quite well,” Paller said.

When implicit recognition took place, EEG signals were recorded from a set of electrodes placed on each person’s head. The brain waves were distinct from those associated with conscious memory experiences. A unique signal of implicit recognition was seen a quarter of a second after study participants saw each old image.

“The novel results show that when people try to remember, they can know more than they think they know,” Paller said.

The study builds upon a body of research that shows that amnesia victims with severe memory problems often have strong implicit memories.

The study suggests that we shouldn’t rely only on conscious memory, Paller concludes. “It suggests that we also need to develop our intuitive nature and creativity." Intuition may have an important role in finding answers to all sorts of problems in everyday life.