Article

Functional Connectivity Networks in the Autistic and Healthy Brain Assessed using Granger Causality

Department of Engineering Technology, University of Houston, Houston, TX, USA.
Conference proceedings: ... Annual International Conference of the IEEE Engineering in Medicine and Biology Society. IEEE Engineering in Medicine and Biology Society. Conference 08/2010; 2010:1730-3. DOI: 10.1109/IEMBS.2010.5626702
Source: PubMed

ABSTRACT

In this study, we analyze brain connectivity based on Granger causality computed from magnetoencephalographic (MEG) activity obtained at the resting state in eight autistic and eight normal subjects along with measures of network connectivity derived from graph theory in an attempt to understand how communication in a human brain network is affected by autism. A connectivity matrix was computed for each subject individually and then group templates were estimated by averaging all matrices in each group. Furthermore, we performed classification of the subjects using support vector machines and Fisher's criterion to rank the features and identify the best subset for maximum separation of the groups. Our results show that a combined model based on connectivity matrices and graph theory measures can provide 87.5% accuracy in separating the two groups. These findings suggest that analysis of functional connectivity patterns may provide a valuable method for the early detection of autism.

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Available from: George Zouridakis, Jun 21, 2014
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    • "Lastly, pairwise coherence estimates are not precise in their anatomical locations as there is a presumption of a two dimensional and not a 3-dimensional space (Black et al., 2008). It has further been observed that multivariate strategies to assess coherence metrics are more accurate and effective than their pairwise counterparts (Kus et al., 2004; Barry et al., 2005; Pollonini et al., 2010). For example, Duffy and Als (2012) used principal components analysis of coherences (multivariate approach) and demonstrated the ability to distinguish between children with autism and neurotypical controls. "
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    • "In addition, EEG technology has been able to demonstrate long-range, anterior to posterior and temporal hypocoherences (Coben et al. 2008 ;Murias et al. 2007). It has further been observed that multivariate strategies to assess coherence metrics are more accurate and effective than their pairwise counterparts (Barry et al. 2005 ;Kus et al. 2004 ;Pollonini et al. 2010). A clinical example is presented below in Fig. 12.3 . "

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