In a series of studies, researchers found highly trained dogs may be more successful than untrained pets in independently solving newly-presented problems.

Researchers have discovered that one of the factors underlying this process may be persistence (坚持). It involves reinforcement, the principle that behaviors that are rewarded become stronger and more frequent. The other side of this is extinction, which refers to the fact that behaviors that are not rewarded grow weaker and become less likely to appear. When extinction sets in, the animal will simply quit before the problem is solved. It is possible that highly trained dogs have learned to persist and thus have developed resistance to extinction, which would make them better problem solvers.

In this recent study, the researchers looked at 26 adult dogs divided into two groups, “trained dogs” and “pet dogs”. There were two tasks that the dogs were tested on. One was a social learning task where the dog had to learn to look directly into the experimenter’s eyes. Every time the dog stared at the experimenter’s face, they received a treat (reinforcement). Once the dogs were performing this task, the extinction stage began, and the staring behavior was no longer rewarded in order to see how persistent the newly learned behavior was.

The second task focused on problem-solving. It involved a flat disk that had bone-shaped plastic bones. The dogs had to learn to remove the plastic bones to obtain the treat hiding under each one. After the series of rewarded trials, the extinction stage began, and no more reinforcements were provided for removing the bones.

In the social learning task, the trained dogs gazed at the experimenters more than the pet dogs during extinction. While in the problem-solving task, the trained dogs picked up a larger number of bones during extinction. In other words, for dogs who had been trained, their newly learned behaviors persisted longer and were stronger than the behaviors of the pet dogs who received no training in any area.

With the growing trend of listening to stories on meditation apps(冥想应用), travel tales—sometimes featuring surrounding sounds of places such as rainforests in Borneo—are helping people get restful sleep. Imagine a voice softly telling as listeners close their eyes and snuggle down in their beds. Are you paying attention? Actually, it doesn’t matter.

According to the CDC, some 70 million Americans struggle with chronic sleep problems. To help with this, many adults are bringing back bedtime stories through meditation apps. Nearly a third of the Calm app’s 300 bedtime stories, which have been listened to more than 450 million times, are about travel. Some 45% of the bedtime stories on the app Breethe are travel-related. Earlier this year, half of the top 10 bedtime stories were travel-themed.

Travel bedtime stories are typically an audio retelling of a trip and rely heavily on descriptions, with occasional surrounding noises like ocean waves, train tracks, or soft music. Train stories are particularly popular at bedtime. “You need movement in a bedtime story—if things are static(静止的), it’s too dull and the listener will get restless,” says Martha Bayless, a professor at the University of Oregon’s Folklore and Public Culture Program. “But the movement has to be non-threatening and soothing. The train is the perfect vehicle for sleep, engaging the senses in a gentle way.”

One possible reason why travel bedtime stories calm our brains is “mirror neurons(镜像神经元),” says Rachel Salas, a neurologist at Johns Hopkins Center for Sleep and Wellness. “These brain cells might combine our own experiences with someone else’s. For example, a tale of train travel could bring a sense of nostalgia(怀旧)for our own past journeys. The comforting sense of something familiar can help with relaxation and sleep. Additionally, the sound of a train chugging along the tracks serves as a type of white noise that lulls people to sleep,” Salas adds.

“In most travel bedtime stories, nothing much happens,” says Bayless. “The bedtime stories are about the quiet period between adventures, which is what sleep is also about.”