International Meeting for Autism Research: Atypical Object Processing in Children with Autism and Its Relationship to Research Diagnosis

Atypical Object Processing in Children with Autism and Its Relationship to Research Diagnosis

Saturday, May 22, 2010
Franklin Hall B Level 4 (Philadelphia Marriott Downtown)
9:00 AM
J. P. McCleery , School of Psychology, University of Birmingham (UK), Edgbaston, Birmingham, United Kingdom
V. Vogel-Farley , Children's Hospital Boston, Boston, MA
C. A. Nelson , Medicine, Children's Hospital Boston, Boston, MA
Background: Previous studies have utilised event-related potentials (ERPs) to document atypicalities in early-stage facial emotion processing, as well as in both face and object processing, in children diagnosed with autism spectrum disorders. Among the atypicalities that have been observed are reduced differentiation of fearful and neutral faces in the N170 component (Dawson, Webb, Carver, Panagiotides, & McPartland, 2004), and reduced amplitude N170 responses to objects (Webb, Dawson, Bernier, & Panagiotides, 2006).

Objectives: In the current study, we assessed fearful versus happy face emotion processing and face versus object processing in children with autism spectrum disorders and control children in a single experiment. The goal of this research is to examine the processing of a new facial emotion contrast (fear vs happy), as well as the processing of face versus objects, in a single group of children.

Methods: ERPs were recorded while 3- to 5-year old high-functioning children (IQ > 80) diagnosed with autism spectrum disorders (ASD) and typically developing (TYP) control children viewed pictures of faces posed in emotional expressions (happy, fearful) and objects (drums, guitars). Faces and objects were presented separately in several short (~6 minute) blocks of trials, with face/object block order counterbalanced both within and across participant groups. Then, both the amplitudes and latencies of the N170 component were examined using Analyses of Variance (ANOVAs) in order to test the hypotheses that a) fearful vs happy face processing, and b) face vs object processing, differed between participant groups.

Results: N170 component amplitudes and latencies did not differ for happy versus fearful faces in either group of children, and there were no differences in emotional face processing between children with and without autism. Alternatively, for face versus object processing, N170 responses were of significantly larger amplitude for faces than for objects in both groups of children, and there was a significant stimulus type (face, object) by subject group (ASD, TYP) interaction. This interaction was driven by significantly reduced (i.e., less negative) N170 amplitudes in response to objects in the children with autism relative to controls. Furthermore, the inclusion of a third group of children who had received a community diagnosis of autism but who did not meet criteria for an ASD when tested using the Autism Diagnostic Observation Schedule (ADOS) in the laboratory resulted in a further statistical interaction between stimulus type and the subject groups. In this interaction, the degree of object processing atypicality was systematically related to diagnostic grouping (ASD ADOS+: 6.9mV; ASD ADOS-: 4.6mV; TYP: -1.3mV).

Conclusions: In the context of previous research, these results suggest that early-stage object processing atypicalities are robust in young children diagnosed with autism, and further suggest that object processing atypicalities may be meaningfully related to concurrent social and communication functioning in children who have received a clinical diagnosis of autism.

See more of: Neurophysiology
See more of: Neurophysiology
See more of: Brain Structure & Function