People with autism are sometimes described as “seeing the world differently,” often showing a superior perception for details. A new study shows that these superior perception skills are present very early in infancy, long before the onset of any symptoms of autism.
The researchers say these findings may shift scientists view of autism by suggesting that changes in perception are a central feature of the disorder. The majority of research studies have focused instead on language and social interaction impairments, they note.
“The prominence of social interaction and communication problems later in development were very much suggestive of a specific ‘social brain’ deficit,” said Teodora Gliga, Ph.D., of the Babylab, part of the Centre for Brain and Cognitive Development at Birkbeck, University of London.
“Evidence is now accumulating for early differences in non-social motor and perceptual abilities, which calls for a reassessment of developmental theories of autism.”
The researchers made their discovery by studying infants known to be at a higher risk of autism based on the diagnosis of an older sibling. Around 20 percent of younger siblings are diagnosed with autism, while another 30 percent show elevated levels of autism symptoms, according to the researchers.
For the study, the researchers took advantage of the fact that infants will spontaneously orient their gaze to anything that pops out in a visual scene, for example, the letter S in a group of Xs.
To test the infants’ perceptual skill, the researchers used an eye tracker to record the infants’ gazes as they were presented with letters on a screen. The researchers also assessed those younger siblings for signs of autism at nine months, 15 months, and two years using standard screening methods.
The study showed that infants with enhanced visual searching ability at nine months old also had more emergent autism symptoms at 15 months and at two years. The finding suggests that the unusual perceptual ability of those infants is “intrinsically linked to the emerging autism phenotype,” they said in their study, which was published in the Cell Press journal Current Biology.
“We know now that we have to give more attention to possible differences in the development of sensation and perception,” Gliga said.
“It is the sensory unpredictability of social interaction, but also of many other aspects of daily life, that people with autism most often report as distressing, and we hope this study and others will bring autism research questions closer to the needs of those directly affected.”
The new study also suggests that eye-tracking technology may be useful as part of future batteries of screening tests for early signs of autism.
The researchers now plan to explore what exactly makes children with autism better at visual searches. They also want to explore the links between increased visual perception or attention and difficulties in social interaction, learning, and communication.
Source: Cell Press