By the time that autism spectrum disorder (ASD) is reliably diagnosed for the first time, infants affected by ASD already have emotional vulnerabilities that indicate the development of co-morbid affective behaviors and high prevalence in older children, reports one in the study published study Journal of the American Academy of Child and Adolescent Psychiatry (JAACAP).
The authors found that infants with ASD show increased anger and frustration and reduce anxiety in response to naturalistic situations. They also found that the ability to experience pleasure remains intact in the early stages of the disorder.
"ASD occurs in most cases within the first two years of life and affects approximately 1 in 59 children," said lead authors Suzanne Macari and Katarzyna Chawarska, PhD, at the Child Study Center of the Yale School of Medicine at New Haven, CT, USA. UNITED STATES OF AMERICA. "This study documents for the first time that infants with ASD at the earliest age, in whom the disease can be reliably diagnosed, already have emotional vulnerabilities that indicate a risk for comorbid affective and behavioral abnormalities."
The findings are based on a study of infant emotional development referenced for a differential diagnosis of ASD in the northeastern United States and include 43 infants with ASD and 56 non-ASD controls.
Infants 21 months of age were recruited between December 2013 and March 2017. Using a multimodal approach, the researchers examined the intensity of emotional responses across the voice and facial channels to naturalistic situations that were supposed to provoke anger, anxiety, and pleasure.
"The vulnerabilities have nothing to do with autism symptoms and thus contribute independently to the development of complex and highly heterogeneous autism phenotypes," Drs added. Macari and Chawarska. "In addition to social and communicative concerns, clinicians should also focus on the assessment and treatment of affective symptoms in young children with ASD, with the hope of alleviating the severity of comorbid disorders so common in ASD."
The researchers found that when a desired infant object is out of reach, infants with ASD experience an increased intensity of anger and frustration. For new and potentially threatening objects, however, their anxiety intensity is lower than in the comparison groups. While an increased anger response may challenge the emerging emotion regulation system, the attenuated anxiety response suggests an atypical assessment of the threat and risk to safety concerns.
Although there is a belief that children with ASD are not as happy as other children, the study found that the enjoyment of playful situations in children with ASD and control groups was comparable. This suggests that in the early stages of the disorder, the ability to experience pleasure may be intact. The use of this intact emotional competence for therapeutic purposes is essential, as the activation of positive emotions promotes learning and exploration and counteracts stress. Together, the study reveals a surprising and complex emotional landscape of children with ASD and provides a strong motivation to explore the early emotional development of ASD and its role in the development of autism.