Ryuta Kawashima, a professor at the Division of Cognitive Neuroscience Institute of Development, Aging and Cancer at Tohoku University, and colleagues said the study involved some 270 children ages 5 to 18 who watched up to 4 hours of TV a day.
The brains of the children and teens were scanned using magnetic resonance imaging.
The researchers used longitudinal follow-up data on the study participants and found prolonged TV viewing was associated with a negative change in verbal abilities and brain anatomy over time.
The study, published in the journal Cerebral Cortex, found extended TV watching adversely affected neural mechanisms such as verbal abilities.
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