Altered intrinsic functional connectivity of anterior and posterior insula regions in high-functioning participants with autism spectrum disorder

Abstract

Impaired understanding of others' sensations and emotions as well as abnormal experience of their own emotions and sensations is frequently reported in individuals with Autism Spectrum Disorder (ASD). It is hypothesized that these abnormalities are based on altered connectivity within "shared" neural networks involved in emotional awareness of self and others. The insula is considered a central brain region in a network underlying these functions, being located at the transition of information about bodily arousal and the physiological state of the body to subjective feelings. The present study investigated the intrinsic functional connectivity properties of the insula in 14 high-functioning participants with ASD (HF-ASD) and 15 typically developing (TD) participants in the age range between 12 and 20 years by means of "resting state" or "nontask" functional magnetic resonance imaging. Essentially, a distinction was made between anterior and posterior regions of the insular cortex. The results show a reduced functional connectivity in the HF-ASD group, compared with the TD group, between anterior as well as posterior insula and specific brain regions involved in emotional and sensory processing. It is suggested that functional abnormalities in a network involved in emotional and interoceptive awareness might be at the basis of altered emotional experiences and impaired social abilities in ASD, and that these abnormalities are partly based on the intrinsic functional connectivity properties of such a network.

Figure 1

Group statistical maps showing brain regions with significant differences (random effect analysis, P < 0.05 FDR corrected) between connectivity maps of the TD and HF‐ASD group based on: (A) seed ROI “right anterior insular cortex” (RH aIC) (x = 36, y = 16, z = 2); (B) seed ROI “right posterior insular cortex” (RH pIC) (x = 38, y = −10, z = 7); (C) seed ROI “left posterior insular cortex” (LH pIC) (x = −38, y = −12, z = 7); corresponding graphics showing 95% confidence intervals (CI) of functional connectivity in the TD and HF‐ASD group.

Figure 2

Cross‐correlation matrices showing color‐coded t‐values of connectivity between brain regions within the LH aIC network for the typically developing (TD) and high‐functioning autism spectrum disorder (HF‐ASD) group, based on the peak coordinates and 6 mm radius of the main network nodes.

Figure 3

Cross‐correlation matrices showing color‐coded t‐values of connectivity between brain regions within the RH aIC network for the typically developing (TD) and high‐functioning autism spectrum disorder (HF‐ASD) group, based on the peak coordinates and 6 mm radius of the main network nodes.

Figure 4

Cross‐correlation matrices showing color‐coded t‐values of connectivity between brain regions within the LH pIC network for the typically developing (TD) and high‐functioning autism spectrum disorder (HF‐ASD) group, based on the peak coordinates and 6 mm radius of the main network nodes.

Figure 5

Cross‐correlation matrices showing color‐coded t‐values of connectivity between brain regions within the RH pIC network for the typically developing (TD) and high‐functioning autism spectrum disorder (HF‐ASD) group, based on the peak coordinates and 6 mm radius of the main network nodes.