New study links strong pupillary light reflex in infancy to later autism diagnosis

May 7, 2018, Uppsala University
autism
Quinn, an autistic boy, and the line of toys he made before falling asleep. Repeatedly stacking or lining up objects is a behavior commonly associated with autism. Credit: Wikipedia.

A new study published in Nature Communications shows that infants who are later diagnosed with autism react more strongly to sudden changes in light. This finding provides support for the view that sensory processing plays an important role in the development of the disorder.

Despite being defined by symptoms in social communication, researchers are increasingly embracing the view that the earliest signs of may reside in more basic processes of brain development. Also, in the latest edition of the diagnostic manual used to diagnose the condition in many countries, sensory symptoms have been included as defining features.

In the new study, the researchers investigated the pupillary light in 9-to-10 month old - this reflex is a basic regulatory mechanism controlling the amount of light that reaches the retina. The infants who fulfilled criteria for autism at three years of age constricted their pupils more than infants who did not fulfill autism criteria at follow up. Further, the amount of pupil restriction in infancy was associated with the strength of autism symptoms at follow up.

"Earlier studies on older children with autism has suggested a weak pupillary light reflex in this group. These findings motivated us to assess the reflex in infant siblings of children with autism. Most of these infants develop typically, yet the probability of later being diagnosed with autism is considerably higher in this group than in the general population. Surprisingly, we found that in infancy, the group differences were in the opposite direction than in : We found stronger reflexes in the infants later diagnosed with autism than in controls" says Terje Falck-Ytter, Associate Professor at the Department of Psychology at Uppsala University and Principal Investigator for the study.

"We believe the findings are important because they point to a very basic function that has not been studied before in infants with later autism diagnosis."

The study is a part of the larger project Early Autism Sweden (EASE), which is a collaboration between Uppsala University and the Center of Neurodevelopmental Disorders at Karolinska Institutet (KIND) in Sweden. In this particular experiment, data from Sweden were combined with data from a similar longitudinal study of siblings with an older sibling with autism conducted at Birkbeck, University of London (UK). The participants in the current experiment were 9-10-months old when their pupillary light reflexes were examined and were followed until three years, when the diagnostic evaluation was conducted. In total, 147 infants with an older sibling with autism took part in the study, of whom 29 met criteria for autism at follow-up. The study also included a control group consisting of 40 infants from the .

"Currently, autism cannot be reliably diagnosed before 2-3 years of age, but we hope that with more knowledge about the early development of the condition, reliable diagnosis will be possible earlier, which should facilitate early access to intervention and support for the families. New knowledge about early development in autism may also provide new leads on strategies for early intervention" Falck-Ytter says. "Yet, the results in this study demonstrated significant group differences only, and it is too early to say whether the method can facilitate early detection in a clinical context."

Explore further: Reduced attention to audiovisual synchrony in infancy predicts autism diagnosis

More information: Pär Nyström et al, Enhanced pupillary light reflex in infancy is associated with autism diagnosis in toddlerhood, Nature Communications (2018). DOI: 10.1038/s41467-018-03985-4

Related Stories

Reduced attention to audiovisual synchrony in infancy predicts autism diagnosis

January 23, 2018
An ability to integrate information from different sensory modalities is important for infants' development and for their perception of the environment. A new study suggests that infants who pay little attention to synchronous ...

EEG signals accurately predict autism as early as three months of age

May 1, 2018
Autism is challenging to diagnose, especially early in life. A new study in the journal Scientific Reports shows that inexpensive EEGs, which measure brain electrical activity, accurately predict or rule out autism spectrum ...

Study identifies tools to identify patients at risk for autism spectrum disorders

July 17, 2017
A tool intended to detect signs of autism in high-risk infants can be used to help identify and treat patients with tuberous sclerosis complex (TSC), a genetic disorder, who most need early intervention. Moreover, they can ...

Does having a sibling with autism affect a child's language and motor skills?

July 19, 2017
A review of published studies suggests that infants who have siblings with autism spectrum disorder may have less advanced linguistic and motor skills than siblings of children with typical development.

Infants' superior perception linked to later autism symptoms

June 11, 2015
People with autism are often described as "seeing the world differently." They tend to show superior perception for details, like, for example, the autistic artist Stephen Wiltshire's highly accurate representations of cityscapes ...

In autism, the social benefits of being a girl

February 9, 2016
Infant girls at risk for autism pay more attention to social cues in faces than infant boys, according to a Yale School of Medicine study—the first one known to prospectively examine sex-related social differences in at-risk ...

Recommended for you

Screening may miss signs of autism, especially in girls: study

May 21, 2018
(HealthDay)—An important checklist used to screen for autism can miss subtle clues in some children, delaying their eventual diagnosis.

Autism is not linked to eating fish in pregnacy

May 21, 2018
A major study examining the fish-eating habits of pregnant women has found that they are not linked to autism or autistic traits in their children.

Scientists just beginning to understand autistic adults' unique health needs

May 11, 2018
In the 1990s, the prevalence of autism spectrum disorder (ASD) among children rose sharply. These children are now entering adulthood, yet physicians and scientists know very little about the health outcomes they might face. ...

Meet Nao, the robot that helps treat kids with autism

May 9, 2018
(HealthDay)—It may seem counterintuitive, but a robot might help kids with autism interact better with humans.

New study links strong pupillary light reflex in infancy to later autism diagnosis

May 7, 2018
A new study published in Nature Communications shows that infants who are later diagnosed with autism react more strongly to sudden changes in light. This finding provides support for the view that sensory processing plays ...

Scientists find possible autism biomarker in cerebrospinal fluid

May 2, 2018
Autism diagnosis is slow and cumbersome, but new findings linking a hormone called vasopressin to social behavior in monkeys and autism in people may change that. Low vasopressin in cerebrospinal fluid was related to less ...

0 comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.