Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2017 Aug;14(4):046010.
doi: 10.1088/1741-2552/aa6b6b.

Electrophysiological signatures of atypical intrinsic brain connectivity networks in autism

Guofa Shou  1 , Matthew W Mosconi, Jun Wang, Lauren E Ethridge, John A Sweeney, Lei Ding
Affiliations

Electrophysiological signatures of atypical intrinsic brain connectivity networks in autism

Guofa Shou et al. J Neural Eng. 2017 Aug.

Abstract

Objective: Abnormal local and long-range brain connectivity have been widely reported in autism spectrum disorder (ASD), yet the nature of these abnormalities and their functional relevance at distinct cortical rhythms remains unknown. Investigations of intrinsic connectivity networks (ICNs) and their coherence across whole brain networks hold promise for determining whether patterns of functional connectivity abnormalities vary across frequencies and networks in ASD. In the present study, we aimed to probe atypical intrinsic brain connectivity networks in ASD from resting-state electroencephalography (EEG) data via characterizing the whole brain network.

Approach: Connectivity within individual ICNs (measured by spectral power) and between ICNs (measured by coherence) were examined at four canonical frequency bands via a time-frequency independent component analysis on high-density EEG, which were recorded from 20 ASD and 20 typical developing (TD) subjects during an eyes-closed resting state.

Main results: Among twelve identified electrophysiological ICNs, individuals with ASD showed hyper-connectivity in individual ICNs and hypo-connectivity between ICNs. Functional connectivity alterations in ASD were more severe in the frontal lobe and the default mode network (DMN) and at low frequency bands. These functional connectivity measures also showed abnormal age-related associations in ICNs related to frontal, temporal and motor regions in ASD.

Significance: Our findings suggest that ASD is characterized by the opposite directions of abnormalities (i.e. hypo- and hyper-connectivity) in the hierarchical structure of the whole brain network, with more impairments in the frontal lobe and the DMN at low frequency bands, which are critical for top-down control of sensory systems, as well as for both cognition and social skills.

PubMed Disclaimer

Figures

Figure 1
Figure 1
A diagram of all steps involved in EEG preprocessing and quantification of ICN-based functional connectivity abnormalities in ASD: (A) preprocessing steps for individual’s EEG data to remove artifacts, (B) steps of group-level tfICA method to identify functional ICNs, (C) steps of quantifying ICN-based functional connectivity abnormalities in ASD.
Figure 2
Figure 2
Spatial maps (A) and power spectrum densities (B) of selected independent components reflecting neuronal activities. Components related to nuisance processes are not displayed. FL frontal left, FM frontal midline, FR frontal right, TL temporal left, ML motor left, CM central midline, MR motor right, TR temporal right, PM parietal midline, PB parietal bilateral, OL occipital left, OR occipital right.
Figure 3
Figure 3
Significant within-ICN connectivity (i.e., spectral power) differences between ASD and TD. * p<0.05, ** p<0.01, *** p<0.005.
Figure 4
Figure 4
Significant between-ICN connectivity in the ASD or TD group at four frequency bands: (A) delta, (B) theta, (C) alpha, and (D) beta. The number of significant connectivity in each group was shown in each panel (i.e., the number in parentheses). Squares outlined in red reflect significantly connected ICN pairs for the ASD group, while squares outlined in black denote significantly connected ICN pairs for the TD group.
Figure 5
Figure 5
Significant between-ICN coherence differences between ASD and TD at the delta, theta and beta bands.
See this image and copyright information in PMC

References

    1. Abbott AE, Nair A, Keown CL, Datko M, Jahedi A, Fishman I, Muller RA. Patterns of Atypical Functional Connectivity and Behavioral Links in Autism Differ Between Default, Salience, and Executive Networks. Cerebral Cortex. 2015:1–12. - PMC - PubMed
    1. American Psychiatric Association. Diagnostic and statistical manual of mental disorders. (5th) 2013
    1. Anderson JS, Nielsen JA, Froehlich AL, DuBray MB, Druzgal TJ, Cariello AN, Cooperrider JR, Zielinski BA, Ravichandran C, Fletcher PT, Alexander AL, Bigler ED, Lange N, Lainhart JE. Functional connectivity magnetic resonance imaging classification of autism. Brain. 2011;134:3739–3751. - PMC - PubMed
    1. Assaf M, Jagannathan K, Calhoun VD, Miller L, Stevens MC, Sahl R, O’Boyle JG, Schultz RT, Pearlson GD. Abnormal functional connectivity of default mode subnetworks in autism spectrum disorder patients. Neuroimage. 2010;53(1):247–256. - PMC - PubMed
    1. Barttfeld P, Wicker B, Cukier S, Navarta S, Lew S, Sigman M. A big-world network in ASD: Dynamical connectivity analysis reflects a deficit in long-range connections and an excess of short-range connections. Neuropsychologia. 2011;49(2):254–263. - PubMed

Publication types