Dr. Fancourt told Healthline that it has to do with the rapid changes in images, sounds, and actions that your brain processes while you’re passively receiving information.You aren’t interacting with what you’re seeing in the way you would when playing a video game or researching something online.“Watching television has been shown in laboratory studies to lead to a more alert but less-focused brain. Some television viewing is stressful, and stress is also associated with impairments in cognition,” she said.“Watching television for more than 3.5 hours per day may also take up time that could be spent on other cognitively beneficial activities, such as playing board games and reading.”
Tina Hoang, MPH, a research associate at University of California, San Francisco, said that a lot remains unknown about the long-term effects that binge-watching can have on the brain, and more studies are needed to determine the mechanisms in which it could increase the risk of cognitive decline.“With binge-watching, as the authors note, it could be that TV watching is mostly a passive activity, but also that there’s extended time spent sitting and being physically inactive,” said Hoang, who was also the lead author on a 2015 JAMA Psychiatry study of how TV viewing impacts cognition in young adults.
“Understanding what about binge-watching affects brain health could help figure out how these behaviors need to be modified,” she added.Research like this can be worrying for people, especially as the passive activity of watching TV becomes more a part of daily life.Television viewing is no longer something done solely on TV sets in living rooms. It’s moved to computers, tablets, and the phones people carry with them all day long.
Hoang said this is a big shift in society that could have lasting effects.“Given the rapid changes in screen-based behaviors over the last few decades, this is a really important issue,” she said.She also pointed out that “we use screen-based tools like phones, tablets, and laptops for many different things, and there have been very few studies of cognitive decline that can really distinguish between the use of these tools and the types of activity people are engaging in.”