Reading on a smartphone promotes overactivity in the prefrontal cortex and lowers reading comprehension, study finds

A new study published in the journal Scientific Reports lends support to a body of research suggesting that reading on electronic devices reduces comprehension. The study found that reading on a smartphone promotes overactivity in the prefrontal cortex, less frequent sighing, and lower reading comprehension.

More than ever, people are reading via electronic devices — for example, consuming news, reading books, and studying for exams on smartphones and tablets. But on top of causing eye strain and headaches, research suggests that using these devices leads to poorer reading comprehension — although it is unclear why.

A sample of 34 university students took part in the experimental study. Each student participated in two reading trials, where they either read a text on a smartphone or read a text on paper. The two texts were passages taken from two novels by the same author, and the conditions were counterbalanced so no student read the same text twice.

While the students read, they wore functional near-infrared spectroscopy (NIRS) headbands that measured activity in the prefrontal cortex and masks around the mouth and nose to measure respiration patterns. After reading, the participants completed a reading comprehension test that included 10 questions related to the content of the passages.

First, the findings revealed that the students performed better on the reading test if they had read the passage on paper versus a smartphone — regardless of which novel they read. This result is consistent with the literature suggesting that reading on electronic devices interferes with comprehension.

Next, the researchers found differences in students’ respiratory activity depending on the reading medium. When reading on paper, the students elicited a greater number of ‘sighs’ compared to reading on a smartphone. A sigh was defined as a breath that was twice the depth of an average breath during a session.

The findings further revealed that the students’ prefrontal brain activity increased during reading, in either condition. But interestingly, this brain activity was higher when reading on a smartphone compared to reading on paper. Moreover, increased activity in the prefrontal cortex was associated with a decrease in sighing and lower reading comprehension.

“There is previous research that shows that even conscious deep breathing has a positive effect on cognitive function, so I propose that those who use electronic devices for long periods of time should include deep breathing in places,” a researcher said.