It may be possible to determine if a child has autism using a sniff test, according to a new study.
A person usually takes a large whiff when faced with nice smell and breathes less when faced with a foul smell. However, a researcher involved in the study and scientist at the Weizzman Institute of Science in Israel Liron Rozenkrantz said that they found that children with autism spectrum disorders do not naturally adjust to the difference in smells.
To explore how children with autism react to smells, researchers built what is called an olfactometer. The device uses a small tube to send different scents directly into the nostrils. A second tube measures the amount of air the children are breathing during each scent, or how much they sniff.
Researchers shared alternating smells with 36 children–18 children with autism and 18 without–using the device. The children experienced anything from a rotten fish scent to the scent of roses, CNN reports.
Children who did not have autism took longer to sniff the pleasant smells than that of the foul smells. The difference in their breathing happened quickly. Children with autism never changed their breathing in response to the smells.
Using the test, researchers who did not know which children had autism were able to identify them 81 percent of the time, according to New York Times. Researchers also discovered that the farther removed a child’s sniff response was from the average child’s (without autism), the more severe their social difficulties were.
The authors suggest that their study may hold some clues as to why children with autism face the social difficulties that they do, Web MD reports. Rozenkrantz said that “sense of smell is a major component of human social interaction.” She added that because olfaction is most likely “altered in autism, could it be that this is a part of the social challenge in autism?”
Rozenkrantz hopes that the tool can be used to diagnose autism at a young age. “This is a nonverbal measure, and it only requires breathing,” Rozenkrantz said.
Though the results are hopeful, more long-term, follow-up studies need to be conducted. The results of the study appear in the July 2 issue of the journal Current Biology.