title: Altered neurophysiological responses to emotional faces discriminate children with ASD, ADHD and ASD+ADHD.
abstract: There are high rates of overlap between autism spectrum disorder (ASD) and attention deficit hyperactivity disorder (ADHD). Emotional impairment in the two disorders, however, has not been directly compared using event-related potentials (ERPs) that are able to measure distinct temporal stages in emotional processing. The N170 and N400 ERP components were measured during presentation of emotional face stimuli to boys with ASD (n=19), ADHD (n=18), comorbid ASD+ADHD (n=29) and typically developing controls (n=26). Subjects with ASD (ASD/ASD+ADHD) displayed reduced N170 amplitude across all stimuli, particularly for fearful versus neutral facial expressions. Conversely, subjects with ADHD (ADHD/ASD+ADHD) demonstrated reduced modulation of N400 amplitude by fearful expressions in parietal scalp regions and happy facial expressions in central scalp regions. These findings indicate a dissociation between disorders on the basis of distinct stages of emotion processing; while children with ASD show alterations at the structural encoding stage, children with ADHD display abnormality at the contextual processing stage. The comorbid ASD+ADHD group presents as an additive condition with the unique deficits of both disorders. This supports the use of objective neural measurement of emotional processing to delineate pathophysiological mechanisms in complex overlapping disorders.
authors.affiliation: MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, UK; Child and Adolescent Psychiatry, Institute of Psychiatry, King's College London, UK. Electronic address: charlotte.tye@kcl.ac.uk.
authors.forename: Charlotte
authors.initials: C
authors.lastname: Tye
authors.affiliation: Laval University and Institut Universitaire en Santé Mentale de Québec, Québec, Canada.
authors.forename: Marco
authors.initials: M
authors.lastname: Battaglia
authors.affiliation: Academic Centre for the Study of Behavioural Plasticity, Vita-Salute San Raffaele University, Milan, Italy.
authors.forename: Eleonora
authors.initials: E
authors.lastname: Bertoletti
authors.affiliation: Child and Adolescent Psychiatry, Institute of Psychiatry, King's College London, UK.
authors.forename: Karen L
authors.initials: KL
authors.lastname: Ashwood
authors.affiliation: Child and Adolescent Psychiatry, Institute of Psychiatry, King's College London, UK.
authors.forename: Bahare
authors.initials: B
authors.lastname: Azadi
authors.affiliation: MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, UK.
authors.forename: Philip
authors.initials: P
authors.lastname: Asherson
authors.affiliation: MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, UK; Child and Adolescent Psychiatry, Institute of Psychiatry, King's College London, UK.
authors.forename: Patrick
authors.initials: P
authors.lastname: Bolton
authors.affiliation: MRC Social, Genetic and Developmental Psychiatry Centre, Institute of Psychiatry, King's College London, UK; Swartz Center for Computational Neuroscience, Institute for Neural Computation, University of California San Diego, USA.
authors.forename: Gráinne
authors.initials: G
authors.lastname: McLoughlin
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D001921:Brain / Q000503:physiopathology*; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000150:complications / Q000175:diagnosis* / Q000503:physiopathology; D003937:Diagnosis, Differential; D004569:Electroencephalography; D004644:Emotions / Q000502:physiology*; D005071:Evoked Potentials / Q000502:physiology*; D005145:Face; D005149:Facial Expression; D006801:Humans; D008297:Male
keywords: ADHD; ASD; Comorbidity; Emotion; Event-related potentials (ERP)