研究：老年人买便宜货可增强记忆力

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

研究人员发现，购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.

美国杜克大学（Duke University）的科学家们观察到，老年人在作出购物决定（尤其是那些要依靠记忆力的决定）时，似乎需要动用额外的脑力。

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.

为了作出购物决定，老年人会用一个额外的大脑区域去记住各类产品，然后从中挑选出最优的——这意味着他们不会错过任何一件便宜货。

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

这项研究发表于11月19日的《神经科学杂志》（Journal of Neuroscience）。项目负责人尼科尔·莱特霍尔（Nichole Lighthall）认为：“事实上，此研究能为医学界带来一个明朗的未来。”

'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.'

他说：“这项研究表明，对于健康的老年人来说，即使他们的记忆力略有减退，他们也能轻易调动平时很少刺激到的大脑区域。这似乎能让他们的表现更佳。”

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位年轻人（平均年龄25岁）和22位老年人（70岁左右）参与了该研究。他们需要浏览一些标有价格星级的商品图片——类似于浏览亚马逊（Amazon.com）等购物网站，与此同时，研究者用功能性磁共振成像技术(fMRI)扫描他们的大脑。

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.

参与者的任务是在一张张图片被展示时“不停地购买”，同时还要记住每件商品的价格。

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，参与者要在两个竞争商品中选出较好的一个，比如在两件毛衣中选出较有价格优势的那件。

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.

当两张竞争产品的图片依次展示时，这样的测试难度不大；但当两张图片之间插入其他干扰项后，测试会更富挑战性。

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

研究发现，老年人作决定的速度和准确度与年轻人不相上下。

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.

扫描结果还显示，除了大脑活动的正常模式外，老年人在需要记忆力时，会动用他们大脑的另一个区域——腹内侧前额皮质(the ventromedial prefrontal cortex，简称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在大脑处理风险评估时具有重要作用，并且能帮助人们感知奖励和情绪。研究表明，该区域越活跃，参与者在任务中的表现越好。

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.

杜克大学脑心理学和神经学教授罗伯托·卡贝扎（Roberto Cabeza）认为：研究表明，人们可通过一些潜在的方法，去治疗有决策障碍的老年人。

'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.

他说：“比如，未来研究中可能会发现让vmPFC活跃的条件，并找出方法去改善老年人的这种条件。”