When phone notifications interrupt our train of thought it's called the 'switch cost' - here's what it means

When phone notifications interrupt our train of thought it's called the 'switch cost' - here's what it means



  • It's easy to get addicted to your smartphone.
  • According to a recent study, notifications could also be messing with your brain chemistry.
  • When a message or alert comes in, we have to divert our attention away from what we were doing.
  • This is called "switch cost," and it's a highly inefficient way of working.
  • Smartphones aren't necessarily evil, but it might be a good idea to come up with a way to limit your use if you're constantly on edge.

Scientists are pretty confident smartphone use can be addictive. When your screen blinks, it's hard to not immediately check out who's contacting you, or which media organisation sent you some alarming news.

We are constantly inundated with such messages, so it's hard to imagine a life without them. But an ever increasing body of scientific evidence suggests it's doing us harm.

For instance, constant awareness of being notified may put us on high alert, and when we receive messages we actually ignite our fight or flight response. Your body releases stress hormones, so you are ready for action to run away from a predator or fight for your life, when in reality, all you do is pick up your phone.

According to a study, presented at the annual meeting of the Radiological Society of North America last November, the interruptions from alerts to your smartphone could be altering your brain chemistry.


Your phone sitting there, constantly lighting up throughout the day creates this pattern in the brain scientists call "switch cost."

It essentially means when there is an interruption, such as a notification, we switch our attention away from the task, then have to return afterwards - which is costly in terms of brain power, as well as time.

"We think it interrupts our efficiency with our brains, by about 40%," Scott Bea, a psychologist at Cleveland Clinic told CBS. "Our nose is always getting off the grindstone, then we have to reorient ourselves."

The team recruited 19 young people, with a mean age of 15 and a half, who were diagnosed with a smartphone addiction, and also a control group containing people of the same age and gender. The addicted group were given nine weeks of cognitive behavioural therapy, modified from a treatment program for gaming addiction.

They were also asked questions about the severity of their addiction, and how it affected their daily routines, social life, productivity, sleep, and feelings.


"The higher the score, the more severe the addiction," said Hyung Suk Seo, a professor of neuroradiology at Korea University in Seoul, and lead author of the study.

Addicted teenagers also had significantly higher scores in depression, anxiety, insomnia, and impulsivity, he added.

Constantly waiting for the next notification can put you on edge, meaning when it comes, your body releases cortisol, causing you heart rate to jump. Being away from your phone can also cause some people to have feelings of panic, known as phone separation anxiety.

It's difficult to get away from your phone, but it can be done with a little patience. After a while your brain will stop trying to convince you you're missing out on something, and you'll be better able to get through the day without constantly checking if someone wants to know what's up.

Staring at a screen at all hours also messes with our biology and makes it harder for us to sleep as it inhibits the release of melatonin - the sleepy hormone. So reducing that time, especially in the evening, will probably help you drift off to sleep a lot easier.


All this being said, it's not that phone use is necessarily the root of all evil. In fact, one study found how too much screen time is problematic, but just less than an hour a day can be beneficial.

Nonetheless, most of us could probably do with putting our phones a way a little more often. If you find you get stressed out easily about who is or isn't texting you back, or you can't help but instantly check when a message comes in, you might want to try giving yourself periodic times during the day to look at your phone. And if that doesn't work, there's always Arianna Huffington's phone bed.