American smartphone users check their smartphones 150 times per day, according to one U.S. study. As of August 2014, the average American spent 7 hours more per day on their smartphones than they did in 2013. What does this intense smartphone use do to our bodies?
A group of neuroscientists from the University of Zurich, led by Arko Ghosh, set out to answer this question in a study published recently in Current Biology. The researchers sought to measure the effect of smartphone use on the brain’s elasticity. That is, does smartphone use impact the way our brains work? Will there be a portion of college biology textbooks that someday refer to the adoption of smartphones as the iBrain or the Steve Jobs Effect?
When Ghosh and colleagues began to look for possible changes in the brain-thumb relationship from smartphone use, they reviewed previous neuroscience research conducted on musicians.
Music is a hobby of mine, and I play several instruments. At the very peak of my training, I might have practiced for two hours a day. But those occasions were incredibly rare. I practiced enough, however, to read music fluently and my fingers respond at lightening speed to the notes, as they do to my Qwerty keyboard.
But my instrumental practice and the eight hours per day I spend at a keyboard pale in comparison to the potentially brain-altering time I spend with my smartphone.
International Smartphone Usage Trends
Mobile penetration is 70% in the U.S., according to Nielson. Smartphone penetration is similar among other developed nations. Penetration is 71% in the UK, 72-80% in Canada (depending on province), 73% in Saudi Arabia and 74% in the UAE. In Australia, penetration is high at 83%.
Smartphone usage is growing in the developing world as well, though smartphone users remain somewhat rare according to the Pew Research Global Attitudes Project.
Among the developing countries included in Pew’s project, Lebanon has the highest smartphone penetration at 45%. Penetration for the next three closest countries is Chile at 39%, Jordan at 38%, and China at 37%.
This Is Your Brain on a Smart Phone
Ghosh and his team examined self-reported age at onset of smartphone use; built-in battery logs to determine how much time users spent on their smartphones; and the time elapsed from the most recent period of use. They then measured, using electroencephalography (EEG), the strength of brain waves in response to mechanical touch on the thumb, index, and middle fingers.
The thumb-brain connection was different for those using smartphones. The amount of activity in the cortex of the brain associated with the thumb and index fingertips was directly proportional to the intensity of phone use.
The thumb tip was even sensitive to day-to-day fluctuations: the shorter the time elapsed from an episode of intense phone use, the researchers report, the larger was the cortical potential associated with it.
Smartphones: A Game Changer for Brains
These findings suggest to the researchers that repetitive movements over the smooth touchscreen surface reshape sensory processing from the hand, with daily updates in the brain's representation of the fingertips.
Smartphones are a great way to gather data about our daily activities without an observer effect, according to Ghosh.
“We must appreciate how common personal digital devices are and how densely people use them… The digital history we carry in our pockets has an enormous amount of information on how we use our fingertips (and more).”
While more research is needed, Ghosh’s work may raise some concern for heavy smartphone users. Researchers have only begun to dig into what these changes may mean for our future lives.
Jenn Lonzer has a B.A. in English from Cleveland State University and an M.A. in Health Communication from Johns Hopkins University. Passionate about access to care and social justice issues, Jenn writes on global digital health developments, research, and trends. Follow Jenn on Twitter @jnnprater3.