Early Television Exposure and Subsequent Attention Problems in Children

Abstract

The study by Christakis et al,1 relating the amount of children’s television exposure at ages 1 and 3 years to later attention problems, is important and long overdue. Their systematic approach, their inclusion of a wide variety of variables, and the size of the group all lend credibility to their findings, which create a new imperative for follow-up investigations. Additional studies should, among other things, quantify more specifically the diagnosis of “attentional problem,” investigate the potential mechanisms underlying this relationship, parcel out the effects of various types of content, and ultimately seek specific causal variables, if any exist.Neuroscience increasingly confirms the power of environmental experiences in shaping the developing brain because of the plasticity of its neuronal connectivity. Thus, repeated exposure to any stimulus in a child’s environment may forcibly impact mental and emotional growth by either setting up particular circuitry (“habits of mind”) or depriving the brain of other experiences. This shaping process, which affects brain structure and function, seems to influence both cellular development and neurotransmitter regulation. Although little research has targeted specifically the developmental trajectory of the brain’s attention systems, which include interlocking feed-forward and feedback loops and associated catecholamine neurotransmitters in prefrontal and subcortical areas,2 there is every reason to believe that their gradual maturation implies a degree of malleability to environmental influences. One of the most interesting questions yet to be addressed is: To what degree can catecholamine mechanisms, which have been implicated in stimulus-seeking and addictive behaviors as well as in attention disorders, be “set” by childhood experiences such as exposure to arousing types of electronic media (eg, television and video games)? Also in question is whether the insistent noise of television in the home may interfere with the development of “inner speech,” by which a child learns to think through problems and plans and restrain impulsive responding.Research has clearly demonstrated a genetic component in attention-deficit/hyperactivity disorder (ADHD),3 and current treatment methods emphasize well-advertised drugs that purport to normalize catecholamine (dopamine, norepinephrine) function.4 Often, dramatic improvement is seen on a drug regimen, and writing a prescription (after the attention problem manifests itself) is an obvious choice for overscheduled physicians. Yet the contribution of environmental factors to the manifestation and severity of attention disorder has barely been touched by systematic research. This study’s preliminary indication that an omnipresent environmental agent is associated with manifestation of ADHD symptomatology suggests that early preventive efforts should also be part of the doctor’s armamentarium.Guidelines from the American Academy of Pediatrics recommend no “screen time” for children <2 years old, no more than 1 to 2 hours a day of quality television and video for older children, and no electronic media in young children’s rooms. Yet a recent survey found that 43% of children ≤2 years old watch television every day, and 26% have a television in their bedrooms. The study also showed that 68% of children <2 years old spend slightly >2 hours a day using screen media.5 Somehow, the considered message of the American Academy of Pediatrics is not hitting the target.Approximately 3 decades ago, teachers of young children at all socioeconomic levels began to report troubling changes in their students, mainly centering on decreasing abilities to listen, pay attention, and engage in independent problem solving.6,7 Frequently, the teachers blamed the advent of fast-paced, attention-getting children’s programming for this trend. Now that the trend is viewed nationally as an “epidemic” of ADHD, perhaps it is indeed time to ask the research questions so ably initiated by Christakis et al and to consider that pediatricians may have yet one more job to do in early parent education about placing limits on screen time.