The smartphone does a good job at making people appear smarter. The device, for instance, helps users easily look up for new information that they need so they do not look slow-witted, but while the gadget does not actually make us smarter, researchers have found evidence that the gadget indeed has an influence on how the brain works.

For a new study, Arko Ghosh, a neuroscientist from the University of Zurich, and colleagues involved 37 participants, 26 of whom used touchscreen smartphones and 11 were users of so-called old fashioned mobile phones.

The researchers used electroencephalography (EEG), which measures voltages changes in the brain activities of the volunteers, to track the electrical messages that were transmitted to and from the brain and the hands of the volunteers in response to mechanical touch on their fingertips primarily on the thumb, forefinger and middle finger.

Based on the EEG readings, Ghosh and colleagues found distinct differences between the two groups. Compared with conventional phone users, those who used smartphones had fingers and thumbs that were more attuned to touch. The researchers, in particular, observed enhanced electrical activity in the brains of the smartphone users when their thumb, index, and middle fingertips were touched.

The researchers likewise observed that the activity in the brain's somatosensory cortex, which plays a key role in the body's sense of touch, is directly proportional to the frequency of phone use. It also depended on how recently a user had been typing and swiping on the smartphone.

The tip of the thumb was especially sensitive to the daily fluctuations in phone usage. The researchers observed more activity in the brain with shorter period of time that had elapsed since the last intense use of the smartphone's touchscreen.

This suggests that repetitive interaction of the fingers with the surface of the smartphone is training the brain's sensory processing capabilities and that this can be adjusted on demand with phone usage, a phenomenon that researchers claim is an evidence of personal digital technology continuously shaping the brain.

 "Our results suggest that repetitive movements on the smooth touchscreen reshaped sensory processing from the hand and that the thumb representation was updated daily depending on its use," the researchers wrote.

Ghosh and colleagues said that their findings, published in Current Biology on Dec. 23, make sense because of the plasticity of the brain that can be molded by experience.