Several observational studies have indicated a potential correlation between the children’s “screen time” in front of electronic devices and the probability of attention-deficit issues occurring later in life. Unfortunately, there are practical and ethical challenges in evaluating this connection in a closely controlled experiment with humans. A new mouse study, reported on 17 February in Scientific Journals, now offers new evidence that early stimuli similar to that generated by television and smartphones could contribute to adult “distractibility.” The research team behind the Nature study was led by Abraham Zangen of the Ben-Gurion University of the Negev and included David Feifel, M.D., Ph.D., UC San Diego.
In their experiments, researchers subjected a group of juvenile rats to interesting, shifting odors every hour (thought to be similar to complex visual stimuli encountered by young children using electronic media), while other young rats were exposed to the same odor-free mixture. This daily dose was given for five weeks- a mouse-time equivalent to pre-puberty and adolescence in humans.
Scientists then studied rats as adults to see how well they handled a typical attention challenge. Adult rats were exposed to volatile odor as juveniles performed significantly worse on the test when disruptive noise was applied to the task compared to animals exposed to stable odors. Dynamic-stimulated juvenile rats also had elevated levels of BDNF protein growth factor in the dorsal striatum, indicating that there were neural changes in that part of the brain. Problems with memory associated with attention deficits, specifically attention deficit hyperactivity disorder, or ADHD) have been linked to that portion of the brain in humans, researchers claim.
Dr. Feifel and his colleagues note that other studies of multisensory stimulation in young rodents appear to improve rather than undermine brain growth. They say more research is required to figure out what kind of stimulus could be beneficial to the brain at an early age, the knowledge that could help direct the creation of electronic media for children.