Neuroimaging Study Of Empathy Deficit In Individuals With Autistic Traits

BackgroundAutism spectrum disorders(ASD) is a group of serious, developmental neuropsychiatric diseases without certain pathogeny. Investigating the cognitive function in individuals with autistic traits(AT) is an important approach to study the pathogenesis of ASD. The Autism-Spectrum Quotient(AQ) is a self-report screening instrument for measuring the severity of AT in the general population. The adaptation and validation of the AQ for the Mandarin Chinese-speaking population is important and necessary for both research and ASD screening purposes. Individuals with AT have cognitive impairments and behavioral manifestations as shown by ASD, and empathy deficit is one of the main manifestations. Pain empathy is one of the usual experimental methods to study empathy. Event-related potentials(ERP) can be used to investigated pain empathy and its time course in individuals with AT. Empathy comprises of cognitive empathy(CE) and emotional empathy(EE), and many brain regions are involved in empathy. Resting-state functional magnetic resonance imaging(rs-f MRI) could be used to study the separate network and the common network underlying the CE and EE, and to investigate whether the brain regions related to AT are involved in regulating CE and EE.Objective1) To investigate the AQ’s psychometric properties of the Chinese version for mainland China; 2) To investigate the pain empathy in individuals with AT using ERP;3) To investigate the neural mechanisms underlying CE and EE and to study whether the brain regions related to AT are involved in regulating empathy.Methods1) In this study, ASD parents and TDC parents were assessed with the Chineseversion of AQ. We examined the differences in AQ scores between the two groups and the gender differences. The psychometric properties(internal consistency reliability, test-retest reliability and discrimination validity) of the AQ were assessed;2) We investigated the neuroelectrophysiological mechanism underlying pain empathy in individuals with AT(AT group) using event-related potentials(ERP). The N1 in early attentional process phase and the late positive potential(LPP, 450-550ms)in late stage of attentional process were measured; 3) We used the amplitude of low-frequency fluctuation(ALFF) to investigate the brain regions related to AT, CE and EE, respectively. And we investigated the brain regions related to both AT and CE,and investigated the brain regions associated with both AT and EE.Results1) We found that ASD parents scored significantly higher than the TDC parents in the total AQ scores(t = 10.89, p < 0.001), and that males scored higher than females(t = 10.53, p < 0.001). The internal consistency of the AQ was satisfactory(Cronbach α: ASD parents/TDC parents = 0.817/0.806) and the test-retest correlation coefficients were 0.79 and 0.89(ASD parents and TDC parents,respectively); 2) We found that in the control group the N1 amplitudes induced by stimuli, including painful stimuli and non-painful stimuli, were larger than those in the AT group. Moreover, the LPP amplitudes induced by painful stimuli in the AT group were larger than those by non-painful stimuli as shown by the control group.However, the effect of pain empathy only occurred in the task of pain judgment, but not in the task of laterality judgment. 3) ALFFs in precentral gyrus,supplementary motor area, middle frontal gyrus, cingulate cortex, insular,hippocampus, middle occipital gyrus, superior temporal sulcus, fusiform gyrus and cerebellum were related with AT. ALFFs in middle frontal gyrus,superior frontal gyrus, precuneus, cingulate cortex, insular and hippocampus and cerebellum were related with CE. ALFFs in fusiform gyrus, superior temporal sulcus,calcarine sulcus, middle occipital gyrus, cerebellum and inferior occipital gyrus were related with EE. Moreover, middle frontal gyrus, cingulate cortex, insular andhippocampus regulate both AT and CE; fusiform gyrus, superior temporal sulcus and middle occipital gyrus regulate both AT and EE.Conclusion1) The results of this current study suggest that the Chinese version of the AQ has good psychometric properties. 2) The subjects in the AT group were insensitive to picture stimulus in the early attention process stage. Moreover, the effect of pain empathy which occurred in the late attention process stage and only occurred in the task of pain judgment need more cognitive control. 3) Our results indicate the existence of distinct neural mechanisms underlying CE and EE. Furthermore, the frontal-temporal circuits regulate both AT and CE, while the temporal-occipital circuits regulate both AT and EE.