Scientists know that our brains shrink with aging, but does less gray matter really matter? Apparently not, according to a new study of 446 people in Australia.
"We found that, on average, men aged 64 years have smaller brains than men aged 60," said Helen Christensen of the Australian National University. "However, despite this shrinkage, cognitive functions -- like memory, attention and speed of processing -- are unaffected."
The conclusion was based on questionnaires and brain scans.
The study, announced Friday, yielded another surprise. Previous studies had indicated that higher levels of education or continuing intellectual activity could serve as a sort of Pilates for the brain, keeping an aging mind fit.
"Our findings do not support these beliefs," Christensen said. "In the present study, we found no relationship between brain shrinkage and education level."
Older minds do sometimes fail, of course, owing to conditions such as Alzheimer’s that scientists are only beginning to understand. Little is known about brain shrinkage, too.
"It is known that the brain shrinks over the course of a person’s life, although the exact trajectory is not well understood, and there are huge individual differences," Christensen said.
科學(xué)家們已經(jīng)得知,隨著年齡的逐漸增長(zhǎng),人們的大腦也會(huì)相應(yīng)地老化,發(fā)生萎縮。而澳大利亞6月10日公布的一項(xiàng)最新研究結(jié)果卻顯示,大腦的萎縮并不會(huì)影響人們的腦部功能。
據(jù)美國“生活科學(xué)”6月10日?qǐng)?bào)道,澳大利亞國立大學(xué)的研究人員通過分析446人的腦部掃描圖以及研究了這些人的問卷調(diào)查結(jié)果后,得出了上述結(jié)論。研究者之一的海倫·克里斯坦森表示:“我們發(fā)現(xiàn),平均起來,64歲的男性其大腦要比60歲的男性的大腦小一些,然而,大腦的一些認(rèn)知功能,如記憶、注意力以及處理問題的速度等,卻都沒有因此而受到影響。”
以前曾有研究顯示,接受高水平教育或是持續(xù)進(jìn)行腦力活動(dòng)可以被認(rèn)為是一種腦部鍛煉,能使逐漸老化的大腦保持健康?死锼固股f:“我們的研究結(jié)果并不支持以前的這些觀點(diǎn),我們?cè)谘芯恐邪l(fā)現(xiàn)大腦的萎縮與受教育水平兩者之間沒有聯(lián)系。”
報(bào)道說,由于老年癡呆癥等一些情況的存在,逐漸老化的大腦有時(shí)確實(shí)會(huì)出現(xiàn)一些問題。但是目前,人們對(duì)老年癡呆癥的了解也是剛剛才開始;而人們對(duì)于腦部萎縮也是知之甚少。對(duì)此,克里斯坦森也表示,雖然人們對(duì)腦部萎縮發(fā)生的準(zhǔn)確軌跡并不十分了解,而且個(gè)體之間也存在著很大的差異,但目前據(jù)人們所知腦部萎縮的過程會(huì)貫穿一個(gè)人的一生。