Apparently, time spent viewing screens can stunt development of white matter in the brains of 3- to 5-year-olds, according to recent research by John Hutton, a pediatrician at Cincinnati Children’s Hospital, the study leader.

On the other hand, the article points out that:

Daniel Anderson, a professor emeritus in psychological and brain sciences at the University of Massachusetts Amherst, who was not involved in the study, says that while it’s easy to jump to the conclusion that screen time is bad for kids, there are alternative explanations for the result. “We know that real-time interactions with adult caretakers are really important for language development in young children, and we know that screens can’t fill that gap,” he says. “What they may have found simply is that screens are a proxy for minimal parent-child interactions.”

The article goes on to say that Hutton agrees with Anderson’s interpretation. Here is the link to the piece from Elemental Medium:

https://elemental.medium.com/do-screens-really-stunt-kids-brains-b491d62e9ed3