Do babies at risk for autism reach for a rolling ball less?
Six-month-old babies with an autistic older sibling watched a rolling ball just as closely as other babies but were more likely not to move their hands to catch it before it arrived.
Source
Ready, Set, Go! Low Anticipatory Response during a Dyadic Task in Infants at High Familial Risk for Autism
Study at a glance
- Design
- Cohort — Prospective longitudinal comparison of high- and low-familial-risk infants: blind-coded video of a structured ball-rolling game at 6 months, with ADOS-T, Mullen scales and face-preference eye tracking at 14 months.
- N
- N=109 · 109 infants coded at 6 months (66 high-risk siblings of autistic children, 43 low-risk); 86 of them contributed 14-month ADOS-T, Mullen and eye-tracking data.
- Population
- Infants aged about 6 months in a Johns Hopkins/Kennedy Krieger prospective sibling study, with or without an older sibling diagnosed with autism
- Outcome
- Anticipatory hand/arm movement toward an approaching ball (0-3 maturity score); at 14 months, ADOS total score, sensorimotor composite and preference for faces over toys
Structured fields used in claim comparison tables when every cited study has a complete layer.
What they did
An examiner played a simple game with 6-month-old infants: bounce a ball while smiling, roll it toward the baby, and see how the baby responded. Coders blind to group rated whether babies looked at the ball and examiner and whether, and how maturely, they moved a hand toward the ball before it touched them. The 66 high-risk infants had an autistic older sibling and the 43 low-risk infants did not; motor skills were measured and statistically controlled. At 14 months the children were assessed for autism signs, motor and visual skills, and how much they preferred looking at faces versus toys.
What they found
Both groups attended to the examiner and tracked the ball equally well. But after controlling for age and motor skills, making no anticipatory movement strongly raised the odds of being in the high-risk group, for example 5.78 times the odds compared with a delayed reach. Anticipation at 6 months did not predict autism signs or motor scores at 14 months within the high-risk group, although high-risk children had higher autism scores and lower motor scores overall. Unexpectedly, among babies with a delayed reach, high-risk toddlers later looked at faces much more than low-risk toddlers did.
The limits
What it doesn't show
Familial risk is not a diagnosis: most high-risk infants will not develop autism, and no diagnostic outcomes at 24 or 36 months were available, so the study cannot show that low anticipation predicts autism itself. The follow-up at 14 months found no link with autism signs, possibly because many children are still before symptom onset at that age. The sample was modest and split into four anticipation levels, making some cells small, and the face-preference interaction was unexpected and needs replication. The task cannot pin down whether the missing reach reflects poor visual-motor integration, motor planning or understanding of the social game.
Key terms
- High familial risk (infant siblings)
- Infants who have an older sibling diagnosed with autism, who therefore have a higher chance of developing autism themselves.
- Anticipatory response
- Starting an action, such as reaching, before a moving object arrives, based on predicting where and when it will be.
- Visual-motor integration
- Using visual information to plan and guide movement, also called perception-action coupling.
- Prodromal period
- The early phase before a condition's full symptoms appear, when subtle signs may already be present.
- ADOS
- The Autism Diagnostic Observation Schedule, a standardised play-based assessment where higher scores indicate more autism-related behaviours.
- Odds ratio
- How much a factor multiplies the odds of an outcome, here the odds of belonging to the high-risk group.
Flashcards
0 of 11 answers reviewed
Research intelligence for this paper
See its role on concept claims, tensions it is part of, placement history, and related discoveries.
Quiz yourself
What behaviour most clearly distinguished high-risk from low-risk 6-month-olds?
Common questions
Could the high-risk babies just have weaker motor skills?
The authors controlled for fine and gross motor scores and age, and the anticipation difference remained, so general motor immaturity does not fully explain it.
Were the high-risk babies simply not paying attention?
No. Both groups looked at the examiner and followed the ball at similar rates, and all babies explored the ball afterwards; the difference lay in turning what they saw into a timely movement.
Does this give us an early test for autism?
Not yet. The anticipation score did not predict autism signs at 14 months, and diagnoses at later ages were not available, so it is a group-level difference rather than a screening tool.
More on Autism