Infants who infrequently gaze at other people when unprompted may be at a higher risk for autism, says new study by the Kennedy Krieger Institute.
The study, published in the September issue of the Journal of Child Psychology and Psychiatry, also found that six-month-old, high-risk infants demonstrated the same level of cause and effect learning skills as low-risk infants of the same age.
The researchers observed 25 six-month-old siblings of children with autism (high-risk group) as well as 25 six-month-old infants with no family history of the disorder (low-risk group) with the intent of assessing cause and effect learning and levels of social engagement. The infant siblings of children with autism are considered at high risk for the disorder because they are 25 times more likely to develop autism.
Kennedy Krieger researchers, in collaboration with scientists at the University of Delaware, developed a new multi-stimuli social learning task in which infants sat in a custom chair equipped with an easy-to-reach joystick, along with a musical toy to the right and their caregiver to the left.
Researchers were looking at two major indicators: how quickly the infant figured out that the joystick activated the toy and the infant’s level of social interaction with its caregiver.
Scientists discovered that both groups spent about the same amount of time gazing at their caregivers when prompted, such as pointing at the toy and showing excitement. However, the high-risk infants spent less time looking to caregivers and more time concentrating on the nonsocial stimuli (joystick or toy) when the caregiver was not actively engaging them. These results could indicate a disturbance in development related to ‘joint attention,’ which is often a core deficiency in children with autism.
“My colleagues and I wanted to create a task that would involve learning something novel and would give babies an opportunity to pay attention to either an object or their caregiver,” said Dr. Rebecca Landa, corresponding study author and director of Kennedy Krieger’s Center for Autism and Related Disorders.
“This study shows that there is a particular vulnerability in high-risk siblings at six months of age. They are not as socially interactive and engaged on their own as their peers, but still respond typically when engaged by their caregivers, making for a subtle difference that could be easily overlooked by both parents and some professionals.”
The results, however, showed no signs of impaired associative learning in the high-risk infants. Both groups demonstrated cause and effect learning abilities; once the infants figured out that pulling the joystick activated the toy, they increased their pulling in order to activate the toy’s music. This finding supports past research that has demonstrated associative learning as a relative strength in older individuals with autism. It may also help clarify why children with autism respond favorably to teaching approaches that use a predictable reward system for desired behaviors.
“Babies in both groups of the study learned the multi-stimuli task to the same degree,” said Dr. Landa. “While the high-risk siblings are at a higher risk for developing autism later in life, they still have the capacity to learn cause and effect as well as their low-risk peers at this young age.”
The study proposes that, like older children, infants at high risk for autism may benefit from frequent exposure to simple cause and effect learning opportunities. Landa recommends using simple songs paired with easy, predictable gestures to promote social learning and language, instead of using electronic toys that children can operate with no need for a caregiver’s engagement.
Although participants in this study have not yet reached the age at which the research diagnoses can be confirmed (three years of age), the study findings show the importance of developing social initiation skills in high-risk infants. It is estimated that about 20 percent of the high-risk infants in this study will receive a diagnosis of autism.
This study is the first of its kind, and a followup will soon be published from the Center for Autism and Related Disorders at Kennedy Krieger Institute. The research study was supported by grants from the National Institutes of Mental Health.