Dr. Tobias Grossmann and Professor Mark Johnson of Birkbeck, University of London, used a technique known as near infrared spectroscopy to examine which areas of an infant's brain are activated when paying joint attention to an object.
The researchers found that when the babies engaged in joint attention with the adult they used a specific region of their brain known as the left prefrontal cortex -- an area to the front of the brain involved in complex cognitive and social behaviours.
Two people sharing attention to the same object is known as joint attention and is a vital human social skill necessary for teaching, collaboration and language learning, Grossmann and Johnson say. Impairments in this skill are one of the earliest signs of autism.
The study, published in Biology Letters, said babies were shown computer-animated images of the face of an adult that would make eye contact with the baby and engage in joint attention. In the control conditions, the adult would not make eye contact with the baby.
A non-invasive technique known as near infrared spectroscopy was used to examine the areas being activated in the infant's brain.