Background noise from the radio or TV might be making it harder for your toddler to learn learn new words, a new study has found.
Scientists conducted experiments where children aged around two were taught new words while hearing soft or loud background speech.
Only toddlers exposed to the quieter sounds successfully learned the words.
Further tests showed they were better at grasping the meaning of words that had earlier been learned in a quieter environment.
Psychologist Brianna McMillan, from the University of Wisconsin-Madison, US, said: "Learning words is an important skill that provides a foundation for children's ability to achieve academically.
"Modern homes are filled with noisy distractions such as TV, radio, and people talking that could affect how children learn words at early ages.
"Our study suggests that adults should be aware of the amount of background speech in the environment when they're interacting with young children."
A total of 106 children, aged 22 to 30 months, took part in the study. They were taught names for unfamiliar objects and then tested on their ability to recognise the objects when they were labelled.
The research is reported in the journal Child Development.
The findings may be especially relevant to crowded low-income households that tend to have higher noise levels, the scientists said.