From Science:
Buyer beware: Videos aimed at improving infant and toddler language skills are not as beneficial for language learning as they claim to be, according to a new study. Rather than helping youngsters, such products may actually hurt their vocabularies.
Videos like Brainy Baby and Baby Einstein have been marketed to parents since 1997. The researchers interviewed the parents of more than 1000 U.S. children between the ages of 8 and 16 months, gathering information on the children’s vocabulary and how frequently they watched videos like Baby Einstein. When the team controlled for factors such as socioeconomic status, race, and parental education, it found that Baby Einstein and his ilk are not the geniuses they’re cracked up to be. For every hour per day spent watching the videos, children understood an average of six to eight fewer words than did those of the same age who did not watch them–a 17-percentile drop in vocabulary, the team reports online tomorrow in the Journal of Pediatrics. “There is no clear evidence of a benefit coming from these videos, and there is some suggestion of harm,” says Zimmerman.
More here.