Evaluating Functional Connectivity Alterations in Autism Spectrum Disorder Using Network-Based Statistics

Abstract

The study of resting-state functional brain networks is a powerful tool to understand the neurological bases of a variety of disorders such as Autism Spectrum Disorder (ASD). In this work, we have studied the differences in functional brain connectivity between a group of 74 ASD subjects and a group of 82 typical-development (TD) subjects using functional magnetic resonance imaging (fMRI). We have used a network approach whereby the brain is divided into discrete regions or nodes that interact with each other through connections or edges. Functional brain networks were estimated using the Pearson’s correlation coefficient and compared by means of the Network-Based Statistic (NBS) method. The obtained results reveal a combination of both overconnectivity and underconnectivity, with the presence of networks in which the connectivity levels differ significantly between ASD and TD groups. The alterations mainly affect the temporal and frontal lobe, as well as the limbic system, especially those regions related with social interaction and emotion management functions. These results are concordant with the clinical profile of the disorder and can contribute to the elucidation of its neurological basis, encouraging the development of new clinical approaches.

Dynamic Functional Connectivity Reveals Abnormal Variability and Hyper‐connected Pattern in Autism Spectrum Disorder

“…Similar to our results, another study [Chen, Kang, & Wang, ] found no significant difference in SFC between the ASD and TD groups after FDR correction based on the AAL template. Meanwhile, they also found that the mean maps of SFC [Chen et al, ; Iidaka, ; Pascual‐Belda et al, ] were similar between the ASD and TD groups, which is in line with our findings. More importantly, other factors such as heterogeneous samples and different preprocessing methods could also lead to inconsistent findings.…”

“…On the other hand, differences in the available multiple comparison methods could also explain this variation. Notably, the most significant results [Chen et al, ; Pascual‐Belda, Diaz‐Parra, & Moratal, ; Supekar et al, ] were found in SFC based on an AAL atlas using a network‐based statistic (NBS) approach [Zalesky, Fornito, & Bullmore, ]. This might be due to the fact that FDR correction is more conservative than NBS, especially when the range of connection is large under a low threshold ( P < 0.05).…”

Conexión neuronal en el trastorno del espectro autista

“…Algunos autores sugieren que los niños con TEA muestran un patrón de activación típico con una sobreactivación en aquellos circuitos estructural y funcionalmente más «primitivos» y una falta de conectividad en aquellos cuyo desarrollo es más prolongado en el tiempo, e implican estructuras y respuestas más racionales 21 .…”

“…En este sentido se ha hallado una disminución de las conexiones neurales llevadas a cabo por el sistema límbico, tálamo y cerebelo, sugiriendo una alteración en la maduración del cerebro 21 . El tálamo en conexión con el lóbulo frontal desempeña un papel importante en funciones cognitivas como la memoria y la atención.…”

Altered Cerebellum Spontaneous Activity in juvenile Autism Spectrum Disorders Associated with Cognitive Functions

“…have been reported to be affected in ASD (Hampson and Blatt, 2015;Maximo and Kana, 2019;Pascual-Belda, et al, 2018). Among these brain regions involving in ASD, the cerebellum was one of the most studied brain regions.…”