近日,，一項(xiàng)刊登在Physiology & Behavior雜志上的研究證實(shí)：與那些不怎么喜歡運(yùn)動(dòng)的老年人相比,，經(jīng)常進(jìn)行體力活動(dòng)的老年人的大腦認(rèn)知功能減不易隨著年齡的增長(zhǎng)而退化。
雖然研究前期研究表明了體力活動(dòng)的增加能提高人包括動(dòng)物體內(nèi)的有氧代謝能力以及學(xué)習(xí)能力,，但還不知道是體內(nèi)有氧代謝水平的提高還是參與體力活動(dòng)時(shí)的娛樂(lè)心情增高了我們大腦的認(rèn)知能力,。該項(xiàng)研究揭示了有氧代謝能力的上升而不是體力活動(dòng)本身在提高我們認(rèn)知功能方面發(fā)揮關(guān)鍵作用。
在這項(xiàng)研究中,，研究人員將試驗(yàn)用老鼠選擇性地共繁殖了23代,，以提高老鼠的耐長(zhǎng)跑能力。在這些繁殖了23代的老鼠中,，有些長(zhǎng)跑能力很強(qiáng),，有些老鼠長(zhǎng)跑能力較差。
研究者對(duì)這些老鼠進(jìn)行辨別學(xué)習(xí)測(cè)試的訓(xùn)練,，這一測(cè)試主要用來(lái)計(jì)算老鼠的認(rèn)知能力,。注意的是在老鼠接受訓(xùn)練之前，試驗(yàn)老鼠不能有任何過(guò)多體力運(yùn)動(dòng),。實(shí)驗(yàn)開(kāi)始時(shí),，工作者訓(xùn)練老鼠完成某種動(dòng)作后，給予老鼠食物作為獎(jiǎng)賞,。在這些接受這一訓(xùn)練后,，老鼠基本已熟悉這一規(guī)則，這個(gè)時(shí)候研究人員會(huì)將這一規(guī)則顛倒,，要求老鼠們舍棄舊的規(guī)則,，訓(xùn)練老鼠繼續(xù)學(xué)習(xí)新的規(guī)則。
結(jié)果發(fā)現(xiàn)體內(nèi)有氧代謝能力高的老鼠在學(xué)習(xí)新的規(guī)則方面優(yōu)于有氧代謝能力低的老鼠,，這一結(jié)果暗示有氧代謝能力的大小是影響認(rèn)知能力高低的主要因素,。
研究人員表示：將來(lái)，我們還要重點(diǎn)研究是不是在人身上也會(huì)出現(xiàn)類似結(jié)果,。假如是,，我們希望呼吁老年人多參加體育活動(dòng)來(lái)預(yù)防因大腦老化所帶來(lái)的認(rèn)知功能退化。(生物谷 Bioon.com)
doi:10.1016/j.physbeh.2012.01.011
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PMID:
Selective breeding for endurance running capacity affects cognitive but not motor learning in rats
Jan Wikgrena,Georgios G. Mertikasb, Pekka Raussia, Riina Tirkkonena, Laurayrv inena, Markku Pelto-Huikkoc, Lauren G. Kochd, Steven L. Brittond, Heikki Kainulainenb,et al.
The ability to utilize oxygen has been shown to affect a wide variety of physiological factors often considered beneficial for survival. As the ability to learn can be seen as one of the core factors of survival in mammals, we studied whether selective breeding for endurance running, an indication of aerobic capacity, also has an effect on learning. Rats selectively bred over 23 generations for their ability to perform forced treadmill running were trained in an appetitively motivated discrimination-reversal classical conditioning task, an alternating T-maze task followed by a rule change (from a shift-win to stay-win rule) and motor learning task. In the discrimination-reversal and T-maze tasks, the high-capacity runner (HCR) rats outperformed the low-capacity runner (LCR) rats, most notably in the phases requiring flexible cognition. In the Rotarod (motor-learning) task, the HCR animals were overall more agile but learned at a similar rate with the LCR group as a function of training. We conclude that the intrinsic ability to utilize oxygen is associated especially with tasks requiring plasticity of the brain structures implicated in flexible cognition.
