For middle-aged and older adults, searching the Internet could be a boost to the brain, a new study suggests. 
    In recent years, several studies have showed a link between pursuing activities that keep the mind engaged, such as crossword puzzles and memory games, and a lowered risk of cognitive decline later in life.

    As the brain ages, a number of structural and functional changes occur, including atrophy, reductions in cell activity, and increases in deposits of amyloid plaques and tau tangles (both associated with Alzheimer's disease ), all of which can affect cognitive function. 

    Keeping your brain active could drive some of these brain chemistry signals in the opposite direction compared to where they go as dementia sets in, and now it looks like surfing the Web could be another way to do that. The new study, to be detailed in an upcoming issue of the journal American Journal of Geriatric Psychiatry, looked at the brain activity of 24 neurologically normal volunteers between the ages of 55 and 76 as they searched the Internet. Half of the participants had experience surfing the Web, while the others did not. 

    The researchers used functional magnetic resonance imaging scans to record subtle brain-circuitry changes in the patients as they performed Web searches and read book passages. fMRI scans track the intensity of cell responses in the brain by measuring the level of blood flow through the brain.

    All the study participants showed significant brain activity during the book-reading task, specifically in the temporal, parietal and occipital lobes of the brain, which are involved in controlling language, reading, memory and visual abilities .

    But Internet searches revealed differences between the two groups. While all the participants showed the same activity as during the book-reading, the Web-savvy group also registered activity in the frontal, temporal and cingulate areas of the brain, whereas those new to the net did not. (These areas of the brain control decision-making and complex reasoning.)

    "Our most striking finding was that Internet searching appears to engage a greater extent of neural circuitry that is not activated during reading — but only in those with prior Internet experience," said study leader Gary Small of the Semel Institute for Neuroscience and Human Behavior at UCLA. 

    Compared with reading, the wealth of choices on the Internet requires that people make decisions about what to click on, which engages important cognitive circuits in the brain.

    "A simple, everyday task like searching the Web appears to enhance brain circuitry in older adults, demonstrating that our brains are sensitive and can continue to learn as we grow older," Small said. The work was funded by the Parvin Foundation.

    With more time and experience, the group that was new to the Web could eventually show the same brain activation patterns as their more Internet-savvy peers.

    The researchers noted that more research must be done to address both the positive and negative ways that new technologies might influence the aging brain. 

    一份最新的研究提出,對于中年人和老年人來說,上網(wǎng)瀏覽可以促進(jìn)大腦活動.
近些年來,好幾份研究都顯示,如果多從事一些類似于縱橫拼字游戲和記憶類游戲的活動來保持大腦活力,可以幫助老年人提高抵抗認(rèn)知能力降低之類

    疾病的能力。
    由于大腦老化,許多的結(jié)構(gòu)性和功能性的病變出現(xiàn),包括細(xì)胞活力的萎縮,降低,還有類淀粉斑的沉積和tau糾結(jié)(同時(shí)也可以引起老年癡呆證)增加,所有

    這些都可以影響認(rèn)知功能.
    大腦保持活動就可以在反方向推進(jìn)出許多大腦的化學(xué)信號,做個(gè)比喻就像是癡呆病癥在哪里,這些信號就去哪里,現(xiàn)在看來似乎上網(wǎng)沖浪可以以另一種

    方式來實(shí)現(xiàn)這個(gè)目的.這份研究報(bào)告詳細(xì)發(fā)表在即將發(fā)行的<<美國老年精神病雜志>>上,該研究基于從網(wǎng)上征集的24名年齡在55-76歲之間的精神

    正常的志愿者.其中一半的志愿者有上網(wǎng)瀏覽的經(jīng)歷,而剩下的則沒有。
    研究者讓志愿者上網(wǎng)瀏覽或者看書,同時(shí)使用功能磁共振成像掃描并記錄他們的大腦環(huán)的細(xì)微變化.功能磁共振成像通過測量大腦中血液流動的級別

    來追蹤掃描大腦細(xì)胞反映的強(qiáng)度.
所有參與實(shí)驗(yàn)的志愿者在讀書實(shí)驗(yàn)期間都顯示出顯著的大腦活動跡象,其中非常明確的顯示在大腦的顳葉,頂葉,以及枕葉部位,這些部位都與控制語言

    ,讀,記憶和視覺能力有關(guān).
但是當(dāng)進(jìn)行網(wǎng)絡(luò)實(shí)驗(yàn)的時(shí)候卻在兩組之間顯示出不同.所有的參與者除了顯示出與讀書調(diào)查期間相同的大腦活動跡象外,有網(wǎng)絡(luò)使用歷史的一組還在

    大腦的額,顳,扣帶回等部也展現(xiàn)出活動跡象,反之,第一次接觸網(wǎng)絡(luò)的人卻沒有這些跡象.(大腦的這些地區(qū)是來控制決定和復(fù)雜原因的.)
"我們最驚人的發(fā)現(xiàn)是網(wǎng)絡(luò)實(shí)驗(yàn)顯示上網(wǎng)能使神經(jīng)網(wǎng)絡(luò)環(huán)更寬廣,而這些活動在閱讀實(shí)驗(yàn)中是沒有的----但也是僅僅針對那些先前有過上網(wǎng)經(jīng)歷的人來

    說,"來自UCLA塞默勒神經(jīng)系統(tǒng)與人類行為科學(xué)學(xué)院,同時(shí)也是這次研究負(fù)責(zé)人的Gary Small如是說.
"舉個(gè)簡單的例子,在年長些的人中,每天進(jìn)行上網(wǎng)之類的活動能夠增強(qiáng)大腦環(huán),這說明我們的大腦是敏感的并且即使我們慢慢變老也能持續(xù)學(xué)

    習(xí),"Small說.這項(xiàng)工作的資助來自與Parvin基金會.
    只要有更多的時(shí)間和經(jīng)驗(yàn),這些第一次接觸網(wǎng)絡(luò)的人們最終也能夠像那些有較長上網(wǎng)經(jīng)驗(yàn)的人一樣展現(xiàn)出相同的大腦活動模式.
    研究者提醒人們,應(yīng)該做更多的研究來揭示那些可能會影響老化大腦的新技術(shù)的積極和消極的一面.