Passage4

Questions 16 to 20 are based on the following passage.

But I can't save any money. It's an excuse I hear a lot from which I detect a note of defiance. In the past few years, it has become increasingly frequent, as more and more Americans make less than we spend, eating up the savings in our homes. The national savings rate is declining. And the situation seems to be getting worse.

We certainly know that saving money is good for us. Yet saving for tomorrow is sill a largely ignored and unappreciated skill. The question that naturally follows is: Why? Why don't Americans make saving a priority?

To start with, saving today is much harder. The typical household income has held largely steady for a good half decade, while prices have continued to rise. If

you're having to spend a disproportionate amount of income on food and gas, it's hard to save. Besides, credit became too accessible. For years it was simply too easy to get your hands on money to spend. While banks at one time would not let you spend more than 36 percent of your total income on debt, they stretched that

number to 55 percent during the housing boom. Why save when you could get that big flat-screen TV today and pay for it with mortgage debt that was both cheap and deductible? Last but not least, saving is, was, and always will be no fun. Think about it this way: Choosing to save almost always means opting for delayed gratification instead of immediate gratification. The pleasure of getting something good today is much greater than that in the future even if the reward in the

future is bigger.

Recently, neuroeconomists, a relatively new breed of experts in economics and neuroscience, have started using MRIs (核磁共振成像） to view the brain as it is making money choices. When something we want to buy comes into view, they see the pleasure center firing up. Similarly, getting a few dollars today is more trilling than getting a slightly larger profit tomorrow. And if you have to wait a few months for that gain, it will have to be much bigger in order to arouse the same interest in your brain. Things way off in the future like retirement don't

jostle the pleasure center much at all.

 In the author"s eyes, Americans say they can't save any money because they______