Your smartphone addiction is doing more than giving your thumbs a workout, it is also changing your brain.
A new study suggests that using a smartphone -- touching the fingertips against the smooth surface of a screen -- can make the brain more sensitive to the thumb, index and middle finger tips being touched.
The study, which was published in the journal Current Biology this week, found that the differences between people when it comes to how the brain responds to thumb stimulation is partly explained by how often they use their smartphones.
"I was really surprised by the scale of the changes introduced by the use of smartphones," said Arko Ghosh, of the Institute of Neuroinformatics of the University of Zurich and one of the study's authors, in a news release.
Other research has shown that musicians and expert video gamers show the same type of brain adaptations.
Smartphone use isn't something most people would consider an "expertise," but frequent use of the devices might similarly lead to brain adaptations.
Researchers used an electroencephalography (EEG) device to record the activity that occurred in the brain when people touched their thumbs, index and middle fingers to a mechanical object. They compared the brain recordings of smartphone users and regular cellphone users.
Smartphone users showed enhanced brain activity when their thumbs, index and middle fingers were touched. And the more people used their smartphones, the more brain activity researchers observed when the thumb and index fingers were touched. Thumb use in particular resulted in increased or decreased brain activity if there was more or less cellphone use in a single day.
According to the study's author, it suggests that the brain plasticity that is observed among people with "expert" skills, such musicians, can also be observed in people as a result of our day-to-day interactions with technology.
"I think first we must appreciate how common personal digital devices are and how densely people use them," Ghosh added. "What this means for us neuroscientists is that the digital history we carry in our pockets has an enormous amount of information on how we use our fingertips -- and more."