New research suggests that teenagers who spend more time toggling among a growing number of digital media platforms exhibit a mounting array of attention difficulties and impulse-control problems.

In a group of more than 2,500 Los Angeles-area high school students who showed no evidence of attention challenges at the outset, investigators from the University of Southern California, University of California at Los Angeles and UC San Diego found that those who engaged in more digital media activities over a two-year period reported a rising number of symptoms linked to attention deficit hyperactivity disorder. On average, with each notch a teenager climbed up the scale of digital engagement, his or her average level of reported ADHD symptoms rose by about 10 percent.

In an accompanying editorial, pediatrician Dr. Jenny Radesky wrote that the “always on” quality of digital media may rob the adolescent brain of the ability to rest and refresh in what scientists call the “default mode.” But she also said another explanation could be that digital engagement is displacing sleep and exercise.

Liver cancer death rates in U.S. make sharp climb

Liver cancer death rates jumped 43 percent, the Centers for Disease Control and Prevention said.

The research collected data from U.S. adults 25 and older from 2000 to 2016. Liver cancer rose from the ninth leading cause of cancer death in 2000 to the sixth leading cause of death by 2016. The death rate for men was 2 to 2.5 times the rate for women, the CDC said. Cancer rates increased the most in adults 55 to 64; this rate increased 109 percent from 2000 to 2013, but then remained stable.

News services