Does TV viewing harm kids' brain development?
The conference was sponsored by the Division of Children and Families of the U.S. Department of Health and Human Services.Jane Holmes Bernstein, a researcher at Bostons Childrens Hospital, added that 20 percent of the nations students have disorders of learning and thinking . . . but consume more than 20 percent of school budgets in remedial training.The neuropsychology specialist noted the difficulty of studying how TV affects a complex system such as the rapidly developing brain interacting with the environment. TV is imbedded in a socio-cultural matrix. It may simply be filling a gap. Other cultural factors may be limiting conversation, therefore leading to diminished linguistic skills, Bernstein said.The most dramatic research presented was a se t of experiments on the developing brains of young rats by noted UC-Berkeley brain scientist Marian Cleeves Diamond. She and her colleagues compared the growth of brain tissue in rat pups in enriched environments with those in impoverished environments. Rat pups in enriched environments large, multi-family cages with a variety of toys experienced significantly more brain growth than rat pups in smaller, single-family cages with fewer stimuli.
The growth in brain tissue included blood vessels, nerve cells, dendritic branching, synaptic junctions and cerebral cortex thickness.Diamond found that allowing the deprived rat pups to observe passively the activity in the more stimulating cages yiel ded no measurable benefit in their brain development. Mere observation is not enough to bring about changes in brain growth. The animals must have physical interaction with their environment, she said.Psychologist Daniel Anderson cautioned against concl uding from research on rat pups that heavy TV viewing retards brain development in children. The University of Massachusetts researcher suggested that TV viewing may actually be more interactive than passive.He even suggested that the ability to attend other tasks such as homework while watching TV or listening to the radio may improve a childs ability to concentrate, since the extra stimulus produces a state of increased arousal.Though most conference participants seemed to view TVs harmful influence on children as self-evident, Anderson was one of a handful of contrarians seeking to provide arguments for televisions benificence. Another contrarian, Jennings Bryant of the University of Alabama, attacked criticsof Sesame Street who claimthe programs relatively fast pace clashes with the developmental needs of young children.
He said a recent study comparing editing pace and/or length of shots in TV programs found that prime-time shows such as Coach averaged between 6 and 7 seconds per shot, while Sesame Street shots averaged about 10 seconds.MTV, by contrast, averaged le ss than 3 seconds per shot.Though Bryant was able to demonstrate the more moderate pace of Sesame Street compared to prime-time programs, some participants felt the comparison missed the point. Its quite a commentary on child-rens TV when 10-second shots are considered long, said Jane Healy, following Bryants remarks. Bryant is a former consultant to the Childrens Television Workshop, producer of Sesame Street. Yale University psychologist Jerome Singer called heavy TV viewing a clear hazard to children. He and his wife and fellow researcher, Dorothy, have correlated amounts of TV viewing among children with reading comprehension scores.They found that children who watched the most TV with the least parental supervision had the lowest read ing scores. By contrast, children with low TV-viewing and high parental involvement had the highest scores.How parents mediate their childrens TV viewing is the critical factor, Singer said. Parents who mediated via discussion rather than prescription ( Thats not nice) were more effective, he said. He advised limited doses of TV with very careful parental monitoring. Psychologist Sidney Segalowitz of Canadas Brock University said the growing visual and aural power of television threatens a childs abilit y to control his or her own attentional processes.
An age-old, self-defense brain function called the orienting reflex ensures that we are genetically drawn to novelty. Segalowitz called for research to determine how pervasive is the failure to realize that ones attention has been captured?He also sp eculated that heavy TV viewing among children inhibits self-monitoring, a psychological response that helps the developing child learn how to behave in various social settings. Self-monitoring is not required when watching TV, Segalowitz said. Will television soon become invisible? Its already happening, says Stanford University researcher Byron Reeves.With high-definition pictures and much larger screens, TV is moving toward virtual reality, said Reeves, a communications researcher speaking Oct. 2 at the TV and Preparation of the Mind for Learningconference in Washington, D.C.The heightened sense of being there produced by the new TV technology is more similar to natural experience. Its not that its like the real world. It is the real world, he said.Most Americans no longer watch TV on 19-inch screens, said Reeves, noting that one-third of all TVs sold in the U.S. in 1990 were at least 27-inch models. Meanwhile, sales of TVs with 35-inch screens or larger are growing 100 percent annually.
New TV offers a 16 x 9 ratio of horizontal to vertical, compared to a 4 x 3 aspect ratio for old TV. New TV increases the amount of peripheral vision information while creating a more literal sense of motion. And the bigger more realistic images will require more viewer effort to process and may prove confusing, Reeves said.Our approach-avoidance reactions and other brain functions are not designed for new TV, said Reeves, citing TV experiments he has conducted on college students. The students repo rted higher states of arousal, more intense feeling, but decreased recall of the experience.They liked the experience, but they couldn't remember much about it, Reeves said.