And it could lead to them being less intelligent than kids who grow up in families less addicted to modern technology, warn scientists.
In first study of its kind they showed an infant’s concentration suffers when parents’ eyes wander during playtime.
Psychologist Professor Chen Yu, of the University of Indiana, said: “The ability of children to sustain attention is known as a strong indicator for later success in areas such as language acquisition, problem solving and other key cognitive development milestones.
“Caregivers who appear distracted or whose eyes wander a lot while their children play appear to negatively impact infants’ burgeoning attention spans during a key stage of development.”
Head mounted cameras worn by both caregivers and infants to track eye movements showed when the former’s wandered, due to distractions such as smartphones, the latter’s attention remained focused on an object for less time.
In cases where infants and parents paid attention to the same object for more than 3.6 seconds, the infant’s attention lingered for an average 2.3 seconds more, even after their gaze turned away.
This extra time works out at nearly four times longer compared to infants whose caregivers’ attention strayed relatively fast.
Prof Yu said when the the impact of a seemingly brief few seconds are magnified over a play session, and the months of daily interaction during a critical stage in mental development, the effect grows significantly.
The study published in Current Biology was unique by getting a first person point of view on parents and children playing together in a typical play session at home or day care, allowing both groups to play with physical toys.
Co author Prof Linda Smith said: “Historically, psychologists regarded attention as a property of individual development. Our study is one of the first to consider attention as impacted by social interaction.
“It really appears to be an activity performed by two social partners since our study shows one individual’s attention significantly influence another’s.”
Generally, parents fell into two major groups - those who let the infants direct the course of their play and those who attempted to forcefully guide infants’ interest toward specific toys.
Explained Prof Yu: “A lot of the parents were really trying too hard. They were trying to show off their parenting skills, holding out toys for their kids and naming the objects.
“But when you watch the camera footage, you can actually see the children’s eyes wandering to the ceilings or over their parents’ shoulders - they are not paying attention at all.”
The caregivers who sustained the children’s attention were those who “let the child lead.” They waited until they saw the child expressed interest in a toy and tried to generate interest by naming the object and encouraging play.
Prof Yu said: “The responsive parents were sensitive to their children’s interests and then supported their attention. We found they did not even really need to try to redirect where the children were looking.”
The shortest attention spans were observed in a third group, in which parents displayed extremely low engagement with children while playing. These distracted caregivers tended to sit back and not play along, or simply look elsewhere during the exercise.
Added Prof Yu: “When you have got a someone who is not responsive to a child’s behaviour, it could be a real red flag for future problems.”
Neuroscientist Dr Sam Wass, of the University of Cambridge, who reviewed the findings for the journal, said: “Showing what a parent pays attention to minute by minute and second by second actually influences what a child is paying attention to may seem intuitive, but social influences on attention are potentially very important and ignored by most scientists.”