學(xué)習(xí)困難與大腦的連接方式有關(guān)，而不是與特定的大腦區(qū)域有關(guān)

學(xué)習(xí)困難與大腦的連接方式有關(guān)，而不是與特定的大腦區(qū)域有關(guān)

Millions of children around the world suffer from learning difficulties, which include dyslexia and language processing disorder, and are linked to conditions like dyspraxia, ADHD, and autism spectrum disorder (ASD). It’s long been thought that specific learning difficulties can be traced to specific regions of the brain, but now, a study published in Current Biology has thrown doubt on this assumption, suggesting that learning difficulties are instead the result of how the brain is wired.

全世界有數(shù)百萬兒童患有學(xué)習(xí)困難，其中包括誦讀困難和語言處理障礙，并與運(yùn)動(dòng)障礙、多動(dòng)癥和自閉癥譜系障礙(ASD)等病癥有關(guān)。長期以來，人們一直認(rèn)為特定的學(xué)習(xí)困難可以追溯到大腦的特定區(qū)域，但現(xiàn)在，發(fā)表在《當(dāng)代生物學(xué)》上的一項(xiàng)研究對這一假設(shè)提出了質(zhì)疑，認(rèn)為學(xué)習(xí)困難是大腦如何連接的結(jié)果。

Rachel Baxter

It’s estimated that between 14 and 30 percent of children and adolescents worldwide have learning difficulties severe enough to require additional support. But the root of these difficulties and their associated conditions have long been hazy, and studies have generally focused on one specific diagnosis, like autism or ADHD (attention deficit hyperactivity disorder).

據(jù)估計(jì)，全世界有14%到30%的兒童和青少年有嚴(yán)重的學(xué)習(xí)困難，需要額外的支持。但是這些困難的根源和它們的相關(guān)情況長期以來一直是模糊不清的，研究通常集中在一種特定的診斷上，比如自閉癥或多動(dòng)癥(注意缺陷多動(dòng)障礙)。

To find out more, a team from the University of Cambridge collected data from hundreds of children with learning difficulties. They then fed the data from nearly 500 kids into an artificial neural network, which worked out that different children had different cognitive profiles. The team then used a method called “cross-profiling” to determine that these profiles were connected to learning difficulties. In addition to cognitive information, the neural network examined images of the children’s brains.

為了了解更多，劍橋大學(xué)的一個(gè)研究小組收集了數(shù)百名有學(xué)習(xí)困難的兒童的數(shù)據(jù)。然后，他們將近500名兒童的數(shù)據(jù)輸入人工神經(jīng)網(wǎng)絡(luò)，計(jì)算出不同的兒童有不同的認(rèn)知特征。然后，研究小組使用了一種叫做“交叉剖析”的方法來確定這些剖析是否與學(xué)習(xí)困難有關(guān)。除了認(rèn)知信息，神經(jīng)網(wǎng)絡(luò)還檢測了兒童大腦的圖像。

The researchers only found a weak relationship between cognitive and brain profiles, suggesting that children with one specific cognitive difficulty don’t necessarily have similar brains. And those kids that have similar brains don’t all suffer from the same learning issues. Essentially, brain structure doesn’t seem to be able to explain learning difficulties.

研究人員只發(fā)現(xiàn)了認(rèn)知能力和大腦特征之間的微弱關(guān)系，這表明有特定認(rèn)知困難的兒童不一定有相似的大腦。那些大腦相似的孩子并不都有相同的學(xué)習(xí)問題。從本質(zhì)上講，大腦結(jié)構(gòu)似乎無法解釋學(xué)習(xí)困難。

However, the researchers then turned to the brain’s wiring. They mapped the connections within each child’s brain to see how strong they were. Some children’s brains were wired strongly around specific “hubs” in the brain, while others weren’t. The team found that the “hubbiness” of a child’s brain was strongly connected to their cognitive profile. Children with poorly connected brain hubs were more likely to have learning difficulties. So, it seems that learning difficulties aren’t so much to do with specific regions of the brain, but rather how the brain is wired up.

然而，研究人員隨后轉(zhuǎn)向大腦的線路。他們繪制了每個(gè)孩子大腦內(nèi)部的連接圖，看看他們有多強(qiáng)。一些兒童的大腦強(qiáng)烈地圍繞著大腦中的特定“中樞”，而另一些則不是。研究小組發(fā)現(xiàn)，兒童大腦的“活力”與他們的認(rèn)知能力密切相關(guān)。大腦中樞連接不良的兒童更有可能出現(xiàn)學(xué)習(xí)困難。因此，學(xué)習(xí)困難似乎與大腦的特定區(qū)域并沒有太大關(guān)系，而是與大腦的連接方式有關(guān)。

However, it’s still unclear whether differences in brain connection are actually a cause of learning difficulties, and more research is needed to find out.

然而，大腦連接的差異是否真的是學(xué)習(xí)困難的原因還不清楚，需要更多的研究來發(fā)現(xiàn)。

"We know that the building blocks of brain ‘hubs’ are in place early in life, potentially even before birth," study author Dr Duncan Astle told IFLScience. "But we know little about the factors that shape their emergence over childhood. That’s what we want to learn about next. My hunch is that the brain wiring differences might be both cause and consequence of the learning difficulty. That is, some initial differences in organisation become reinforced over childhood, partly as a consequence of the child’s experience. Small initial differences in brain organisation snowball. But we need a lot more research before we know for sure."

研究作者鄧肯·阿斯特爾博士在接受《IFLScience》采訪時(shí)表示:“我們知道，構(gòu)成大腦‘中樞’的積木在生命早期就已經(jīng)存在，甚至可能在出生之前就存在了。但我們對影響他們童年成長的因素知之甚少。這就是我們接下來要學(xué)習(xí)的內(nèi)容。我的直覺是，大腦線路的差異可能既是學(xué)習(xí)困難的原因，也是學(xué)習(xí)困難的后果。也就是說，一些最初的組織差異在兒童時(shí)期得到加強(qiáng)，部分是由于兒童的經(jīng)歷。大腦組織的微小初始差異就像滾雪球一樣。但在我們確定之前，我們需要更多的研究。”

The findings suggest we need a rethink when it comes to how we look at the link between the brain’s structure and learning difficulties, and how we view specific diagnoses.

這些發(fā)現(xiàn)表明，我們需要重新思考如何看待大腦結(jié)構(gòu)與學(xué)習(xí)困難之間的聯(lián)系，以及如何看待具體的診斷。

“One of the key findings from the paper is that a child’s diagnostic ‘label’ does not correspond well to their cognitive difficulties," said Dr Astle. "So whilst diagnosis is an important milestone for children and families, the ‘label’ itself shouldn’t dictate the kind of support they receive. That is important, because at the moment support is mainly linked to diagnosis.”

阿斯特爾博士說:“這篇論文的一個(gè)重要發(fā)現(xiàn)是，兒童的診斷‘標(biāo)簽’與他們的認(rèn)知困難并不相符。因此，雖然診斷對兒童和家庭來說是一個(gè)重要的里程碑，但‘標(biāo)簽’本身不應(yīng)該規(guī)定他們得到的支持類型。這很重要，因?yàn)槟壳暗闹С种饕c診斷有關(guān)。”