We often just use our sense of sight, touch, smell, and taste to eat food. But what about our sense of hearing? Does sound also affect our dining experience?

A new report answers, “yes, it does.”

That answer comes from researchers at Brigham Young University and Colorado State University in the United States. They found that hearing is important in the eating experience.

Hearing is often called “the forgotten food sense”, says Ryan Elder. Elder is an assistant professor of marketing at Brigham Young University’s Marriott School of Management. He says that if people notice the sound the food makes as they eat it, they might eat less. On the other hand, watching loud television or listening to loud music while eating can hide such noises. And this could lead to overeating.

For the study, the researchers wanted to test whether the sounds of eating—chewing, chomping and crunching(松脆的)—had any effect on how much a person ate. During the experiments, the test subjects wore headphones and listened to noise at either a high or low audio level. Then researchers gave them a crunchy snack: pretzels. The study found that subjects who listened to the higher volume noise ate more pretzels than those with the low audio levels.

Elder says that when hiding I heard sounds of eating, like when you watch television or listen to loud music while eating, we take away the sense of hearing. And this may cause you to eat more than you would normally. The researchers are calling this, the “crunch effect”.

The researchers admit that the effects may not seem like much at one meal. But over a week, a month or a year, all that food can really add up.

Pets are like our family members and their good health is very important to all pet owners. Just as the pollutants in the air affect our health, they can affect our pets too.

【小题1】 57% of dogs exposed to higher pollution levels developed brain diseases and showed signs of neuro(神经)problems. While a more recent study found that cats with breathing problems were more likely to live in households with higher indoor air pollution.

Air purifiers (净化器) have been brought into use in recent years. They work to remove harmful chemicals from the air. 【小题2】 But are they safe for pets? How can we ensure that they aren’t harming our furry friends?

【小题3】 The physical safety of using a mechanical device around pets is what we have to pay attention to. There is an existing risk of our pet becoming trapped in the electrical wire of our air purifier. Air purifiers are designed to be used in the home around children and their internal mechanisms should also be safe from small tails of our pets and other parts of their bodies.【小题4】

Whether the air purifier improves or damages the health of our animals is also something we have to consider. The air purifiers are safe for pets, but only if they do not produce any ozone byproduct (臭氧副产品) . 【小题5】 We should always stay away from the ones that produce even minimal quantities.

Picking the wrong air purifier type can quickly make things worse for our pets. On the other hand, picking the correct air purifier can lead to a big increase in the quality of life for them.

The Vienna-based researchers showed that dogs will stop doing a simple task when not rewarded if another dog, which continues to be rewarded is present.

The experiment consisted of taking pairs of dogs and getting them to present a paw for a reward. On giving this “handshake” the dogs received a piece of food. One of the dogs was then asked to shake hands, but received no food. The other dog continued to get the food when it was asked to perform the task.

The dog without the reward quickly stopped doing the task, and showed signs of anger or stress when its partner was rewarded.

To make sure that the experiment was really showing the interaction between the dogs rather than just the frustration of not being rewarded, a similar experiment was conducted where the dogs performed the task without the partner. Here they continued to present the paw for much longer.

Dr. Frederike Range from the University of Vienna says this shows that it was the presence of the rewarded partner that was the greater influence on their behavior.

“The only difference is that one gets food and the other doesn’t. They are responding to being unequally rewarded.” she says.

The researchers say this kind of behavior, where one animal gets frustrated with what is happening with another, has only been observed in primates (灵长类) before.

Studies with various types of monkeys and chimpanzees show they react’ not only to seeing their partners receiving rewards when they are not, but also to the type of reward.

The dog study also looked at whether the type of reward made a difference. Dogs were given either bread or sausage, but seemed to react equally to either. Dr. Range says this may be because they have been trained.