Many studies have been performed to determine how effectively we read from paper versus an electronic medium such as a computer or smartphone, and the vast majority have concluded we retain more from reading on paper than from an electronic device. Researchers have posited several different theories for the disparity, including multitasking in the electronic environment, the lack of spatial references on screens, and “self-delusion” in screen readers who don’t put in as much effort since they believe their comprehension is good. While all of these are intriguing, no solid consensus has emerged.
Now, however, new research has added to the possibilities. A recent study at Showa University School of Medicine in Tokyo, published in the scientific journal Nature, found a possible answer in a totally unexpected area — sighing.
Citing previous studies that linked visual environment and cognitive performance, the team suspected that visual input might affect brain state and physiological condition, which, in turn, “likely exist as mediating variables in the relationship between the visual environment and cognitive performance.” The physiological condition they chose to measure along with brain activity was respiration. They recruited 34 college students for a study that examined the effects of reading on comprehension by simultaneously measuring brain and respiratory activity before, during, and after reading a select passage.
The 34 participants were given either a smartphone or a paper book that were exactly the same size and weight from which to read novel excerpts. Each person was connected to monitors that measured prefrontal brain activity and respiration (respiratory pattern, metabolic pattern, and number of sighs), and they took part in two randomly conducted trials for each of four conditions (smartphone/paper, novel A/novel B). Each trial consisted of four sessions: resting state before reading, during reading, resting state after reading, and a 10-question reading test.
Once again, those who read from a smartphone scored lower on comprehension than those who read from a paper book. The researchers found that some aspects of breathing and brain activity were similar in both media: the amount of air inhaled and exhaled decreased during reading, breathing grew fast and shallow, and prefrontal brain activity increased.
The big distinction that emerged was in the number of times participants sighed. When reading from paper, the number of sighs increased; when reading from a smartphone, the number of sighs decreased. That led the researchers to conclude that something about reading from an electronic medium appeared to suppress sigh production.
In addition to the difference in sighing, the team also noticed a difference in brain activity. While prefrontal activity increased while reading from both the electronic and paper media, those who read from a smartphone showed overactivity in the prefrontal cortex. Along with other reported associations between prefrontal overactivity and “poor narrative content comprehension,” the researchers suggested an “interactive relationship between sigh inhibition and overactivity in the prefrontal cortex” that could be responsible for the decline in comprehension associated with reading from an electronic device.
Additionally, previous studies have indicated that sighing increases with increased cognitive load. The researchers therefore hypothesized that reading on paper creates a “moderate cognitive load” that may generate sighing, which “appears to restore respiratory variability and control of prefrontal brain activity.” On the other hand, the increased prefrontal activity noted in smartphone reading suggests an “acute cognitive load,” which may inhibit the sigh generation and prevent the restoration of prefrontal activity control.
As a takeaway, the researchers suggest that, if you choose to read from an electronic device, you may want to pause from time to time while reading to take a deep breath, “since sighs, whether voluntary or involuntary, regulate disordered breathing” and lead to more beneficial brain activity. Clearly, more research needs to be done, but the study does posit an interesting possibility for improving digital comprehension.
 n/a. (March 14, 2022). “Why We Remember More When We Read on Paper: The surprising influence of sighing on reading comprehension.” PsychologyToday.com. Retrieved from https://www.psychologytoday.com/us/blog/time-travelling-apollo/202203/why-we-remember-more-when-we-read-paper.
Barshay, Jill. (April 8, 2021). “Evidence Increases for Reading on Paper Instead of Screens.” The Hechinger Report. https://hechingerreport.org/evidence-increases-for-reading-on-paper-ins….
Honma, Motoyasu, et al. (2022). “Reading on a Smartphone Affects Sigh Generation, Brain Activity, and Comprehension.” Scientific Reports, vol. 12, no. 1, https://doi.org/10.1038/s41598-022-05605-0.