TORONTO -- A study says babies exposed to more than one language in the home are more attentive than infants who hear only a single language.

Researchers at Toronto's York University say this advantage in attention can start as early as six months of age and could set the stage for lifelong cognitive benefits.

The research involved measuring babies' eye movements to assess attention and learning. Half of the infants studied were being raised in monolingual environments, while the other half heard two languages in their homes.

The infants were shown images as they lay in a crib equipped with a camera and screen. Their eye movements were tracked as they watched pictures appear above them in varying areas of the screen.

Researchers found that infants in a bilingual home were better at anticipating where the target image would appear compared to those raised with a single language.

Co-author Ellen Bialystok says the difference between monolingual and bilingual individuals later in life is not in the languages learned, but in the attention system used to focus on language.

"This study tells us that from the very earliest stage of development, the (brain) networks that are the basis for developing attention are forming differently in infants who are being raised in a bilingual environment," said Bialystok, a distinguished research professor of psychology.

"Why is that important? It's because attention is the basis for all cognition."

The research was published Wednesday in the journal Developmental Science.