Abnormal autonomic and associated brain activities during rest in autism spectrum disorder

Abstract

Autism spectrum disorders are associated with social and emotional deficits, the aetiology of which are not well understood. A growing consensus is that the autonomic nervous system serves a key role in emotional processes, by providing physiological signals essential to subjective states. We hypothesized that altered autonomic processing is related to the socio-emotional deficits in autism spectrum disorders. Here, we investigated the relationship between non-specific skin conductance response, an objective index of sympathetic neural activity, and brain fluctuations during rest in high-functioning adults with autism spectrum disorder relative to neurotypical controls. Compared with control participants, individuals with autism spectrum disorder showed less skin conductance responses overall. They also showed weaker correlations between skin conductance responses and frontal brain regions, including the anterior cingulate and anterior insular cortices. Additionally, skin conductance responses were found to have less contribution to default mode network connectivity in individuals with autism spectrum disorders relative to controls. These results suggest that autonomic processing is altered in autism spectrum disorders, which may be related to the abnormal socio-emotional behaviours that characterize this condition.

Autonomic and brain responses associated with empathy deficits in autism spectrum disorder

“…Using this model, our findings indicate increased autonomic arousal indexed by SCR when observing others’ pain and decreased overall SCR in ASD participants. Therefore, our results suggest a more complex autonomic profile than previously postulated (Eilam-Stock, et al, 2014; Hirstein, et al, 2001; Kylliainen and Hietanen, 2006), in which sympathetic activity is decreased at baseline in ASD, with dysregulated, heightened sympathetic responses and arousal when viewing others’ pain. These results are consistent with our previous finding of reduced number of non-specific (non-task-evoked) SCRs during rest in participants with ASD (Eilam-Stock, et al, 2014).…”

“…Recently, we demonstrated that SCR was positively correlated with AIC activation in the HC group during rest, while no such correlation was found in the ASD group (Eilam-Stock, et al, 2014). In addition, AIC functional connectivity was abnormal in the ASD participants (Eilam-Stock, et al, 2014), which is in agreement with findings from other studies demonstrating abnormal activity and connectivity of the AIC in individuals with ASD (Di Martino A, K Ross, et al 2009; Uddin LQ and V Menon 2009; Ebisch SJ et al 2011). Functional connectivity during task states, especially directed or effective connectivity during socio-emotional tasks, is under-investigated (Uddin and Menon, 2009).…”

“…A handful of studies have directly examined functional connectivity of the AIC in ASD (Ebisch, et al, 2011; Eilam-Stock, et al, 2014; Price, et al, 2008). Recently, we demonstrated that SCR was positively correlated with AIC activation in the HC group during rest, while no such correlation was found in the ASD group (Eilam-Stock, et al, 2014).…”

“…The AIC is a critical cortical center in the interoceptive system which processes information from the body and exerts autonomic control (Craig, 2009; Craig, 2011; Critchley and Harrison, 2013; Gu, et al, 2013a). For instance, a direct correlation has been found between autonomic activity indexed by skin conductance response (SCR) and neural activity in the AIC measured by functional magnetic resonance imaging (fMRI) during resting state in neurotypical individuals (Eilam-Stock, et al, 2014; Fan, et al, 2012). Using fMRI (Gu and Han, 2007; Gu, et al, 2010; Gu, et al, 2013b), activation likelihood estimate meta-analysis and neuropsychological approaches (Gu, et al, 2012), we previously demonstrated that the AIC is specifically activated during and is necessary for empathetic pain processing.…”

Autism spectrum disorder: neuropathology and animal models

“…The presence of consistently impaired social skills in ASD has prompted an intense exploration of cortical areas implicated in emotional regulation and awareness of oneself and others [95, 131, 133, 241]. Interestingly, a particular population of distinct neurons, the von Economo neurons (VENs), present almost exclusively in the frontoinsular (FI) and anterior cingulate cortices (ACC) have been found to be consistently affected in ASD [4, 104, 256, 258].…”