研究：老年人買便宜貨可增強記憶力

Shopping can boost the brainpower of the elderly, researchers have found.

研究人員發現，購物能提高老年人的智力。

Duke University scientists found older adults seem to need extra brainpower to make shopping decisions - especially ones that rely on memory.

美國杜克大學（Duke University）的科學家們觀察到，老年人在作出購物決定（尤其是那些要依靠記憶力的決定）時，似乎需要動用額外的腦力。

To do this, they discovered they use an additional brain area to remember competing consumer products and choose the better one - meaning they don't miss a bargain. Older shoppers use an additional brain area to remember competing consumer products and choose the better one - meaning they don't miss a bargain.

為了作出購物決定，老年人會用一個額外的大腦區域去記住各類產品，然后從中挑選出最優的——這意味著他們不會錯過任何一件便宜貨。

'The study gives a bright picture, actually,' Nichole Lighthall, who led the research, appearing Nov. 19 in the Journal of Neuroscience.

這項研究發表于11月19日的《神經科學雜志》（Journal of Neuroscience）。項目負責人尼科爾·萊特霍爾（Nichole Lighthall）認為：“事實上，此研究能為醫學界帶來一個明朗的未來。”

'It suggests that for healthy older adults, even though their memory might not be as good, they can naturally recruit other brain regions that are not typically involved in the task.

'It seems that it allows them to perform at a higher level.'

他說：“這項研究表明，對于健康的老年人來說，即使他們的記憶力略有減退，他們也能輕易調動平時很少刺激到的大腦區域。這似乎能讓他們的表現更佳。”

The study used functional magnetic resonance imaging (fMRI) -- a noninvasive technique that indirectly measures changes in brain activity -- to scan the brains of 20 younger adults (25 years old, on average), and 22 older adults (around 70 years old) while the participants viewed pictures of consumer products with star ratings indicating their value, similar to online shopping sites like Amazon.com.

有20位年輕人（平均年齡25歲）和22位老年人（70歲左右）參與了該研究。他們需要瀏覽一些標有價格星級的商品圖片——類似于瀏覽亞馬遜（Amazon.com）等購物網站，與此同時，研究者用功能性磁共振成像技術(fMRI)掃描他們的大腦。

Participants were asked to 'keep shopping' by navigating from one screen to the next while trying to remember the value for each consumer product they encountered.

參與者的任務是在一張張圖片被展示時“不停地購買”，同時還要記住每件商品的價格。

They then had to select the better of two competing products, such as two different sweaters, based on which was a better value.

之后，參與者要在兩個競爭商品中選出較好的一個，比如在兩件毛衣中選出較有價格優勢的那件。

Some versions of the task were easy.

For example, participants saw the first product, then the second product, and were asked to select the better one.

In the more challenging trials, participants were shown the first product, and then had to learn about or 'buy' several unrelated items before being shown the second, competing product and making a decision.

當兩張競爭產品的圖片依次展示時，這樣的測試難度不大；但當兩張圖片之間插入其他干擾項后，測試會更富挑戰性。

Young and old adults made decisions with similar speed and accuracy.

研究發現，老年人作決定的速度和準確度與年輕人不相上下。

In addition to the normal patterns of brain activity, however, older adults used a part of their brain called the ventromedial prefrontal cortex (vmPFC) as memory demand increased.

掃描結果還顯示，除了大腦活動的正常模式外，老年人在需要記憶力時，會動用他們大腦的另一個區域——腹內側前額皮質(the ventromedial prefrontal cortex，簡稱vmPFC)。

The vmPFC is known to be involved in processing risk calculations and it has been shown help people assign values to rewards and emotions.

In this study, the more active the vmPFC was, the better participants performed at the task.

vmPFC在大腦處理風險評估時具有重要作用，并且能幫助人們感知獎勵和情緒。研究表明，該區域越活躍，參與者在任務中的表現越好。

The study could point to potential strategies to rehabilitate decision-making deficits in older adults, said Roberto Cabeza, a professor of psychology and neuroscience at Duke, and a member of the Duke Institute for Brain Sciences.

杜克大學腦心理學和神經學教授羅伯托·卡貝扎（Roberto Cabeza）認為：研究表明，人們可通過一些潛在的方法，去治療有決策障礙的老年人。

'For example, future studies could identify the conditions that lead to vmPFC recruitment during decision-making and explore ways of promoting these conditions when older adults make decisions in real life,' Cabeza said.

他說：“比如，未來研究中可能會發現讓vmPFC活躍的條件，并找出方法去改善老年人的這種條件。”