美國(guó)《科學(xué)新聞》周刊報(bào)道，容易分心的人可以不必再將注意力的缺乏歸咎于王室婚禮和“臉譜”網(wǎng)了。根據(jù)5月4日出版的一期《神經(jīng)科學(xué)期刊》 The Journal of Neuroscience ，研究人員認(rèn)為真正的罪魁禍?zhǔn)滓苍S是大腦左后方的一些腦細(xì)胞。
文章說(shuō)：“了解腦部如何關(guān)注重要的事情（同時(shí)濾除干擾）也許有助于科學(xué)家找到對(duì)付注意力欠缺的方法。”
英國(guó)伯明翰大學(xué)的認(rèn)知神經(jīng)科學(xué)家卡梅爾·梅沃拉克沒(méi)有參與這項(xiàng)研究，他說(shuō)：“注意力對(duì)我們的生活有著巨大的影響。實(shí)際上，我們所做的每一件事都受到注意力的影響。”
報(bào)告的撰寫(xiě)人之一、倫敦大學(xué)學(xué)院的金井良太說(shuō)，在當(dāng)前這個(gè)信息超負(fù)荷的年代，集中注意力并非易事，有些人尤其容易分神。金井和同事想知道腦部結(jié)構(gòu)的不同能否解釋為什么有的人容易分心，而另外一些人則可以全神貫注。
研究人員請(qǐng)145名志愿者填寫(xiě)一張認(rèn)知失誤調(diào)查表，讓填寫(xiě)者評(píng)估自己出現(xiàn)腦力差錯(cuò)的頻率，比如忘了要去商店買什么東西，或者撞上了別人。通過(guò)志愿者的回答可以評(píng)估他們?cè)谌粘Ｉ钪惺欠袢菀壮霈F(xiàn)注意力不集中的問(wèn)題。
腦部掃描結(jié)果發(fā)現(xiàn)，愛(ài)分心與不愛(ài)分心的人確實(shí)存在著差異，前者左側(cè)頭部頂葉皮層區(qū)域的組織密度更大，表明有更多的神經(jīng)細(xì)胞。
很難集中注意力的人其實(shí)擁有更多的腦組織，這樣的研究結(jié)果有點(diǎn)出人意料，不過(guò)腦組織并非多多益善。金井說(shuō)，隨著腦部逐漸成熟，一些不相干的神經(jīng)細(xì)胞連接點(diǎn)會(huì)被去除，而容易分心的人可能缺失了對(duì)于控制注意力來(lái)說(shuō)非常重要的腦部精簡(jiǎn)過(guò)程。
原文出處：
The Journal of Neuroscience, 4 May 2011, 31（18）: 6620-6626; doi: 10.1523/?JNEUROSCI.5864-10.2011
Distractibility in Daily Life Is Reflected in the Structure and Function of Human Parietal Cortex
Ryota Kanai1, Mia Yuan Dong2, Bahador Bahrami1,3,4,5, and Geraint Rees1,3
Abstract
We all appreciate that some of our friends and colleagues are more distractible than others. This variability can be captured by pencil and paper questionnaires in which individuals report such cognitive failures in their everyday life. Surprisingly, these self-report measures have high heritability, leading to the hypothesis that distractibility might have a basis in brain structure. In a large sample of healthy adults, we demonstrated that a simple self-report measure of everyday distractibility accuray predicted gray matter volume in a remarkably focal region of left superior parietal cortex. This region must play a causal role in reducing distractibility, because we found that disrupting its function with transcranial magnetic stimulation increased susceptibility to distraction. Finally, we showed that the self-report measure of distractibility reliably predicted our laboratory-based measure of attentional capture. Our findings distinguish a critical mechanism in the human brain causally involved in avoiding distractibility, which, importantly, bridges self-report judgments of cognitive failures in everyday life and a commonly used laboratory measure of distractibility to the structure of the human brain.
