Superior temporal sulcus hypoperfusion in children with autism spectrum disorder: an arterial spin-labeling magnetic resonance study

Abstract

Advances in neuroimaging techniques have significantly improved our understanding of the neural basis of autism spectrum disorder (ASD). Several attempts have been made to label the main neuroimaging phenotype of ASD, mostly by anatomical and functional activation studies, but none of the frameworks have been without controversy. Over the past decade, a renewed interest for rest brain functioning has emerged in the scientific community, reflected on a large number of resting state fMRI (rs-fMRI) studies, but results remain heterogeneous. It is possible today to investigate rest brain functioning by measuring rest cerebral blood flow (CBF) with MRI using arterial spin labeling (ASL). Here, we investigated rest CBF abnormalities using noninvasive ASL-MRI in 18 children with ASD without cognitive delay (10.4 ± 2.8 y) and 30 typically developing children (10.6 ± 3.0 y). Following quality control, images from a final sample of 12 children with ASD (11.2 ± 2.9 y) and 28 typically developing children (10.1 ± 2.5 y) were analyzed. Whole brain voxel-by-voxel analysis showed significant rest CBF decrease in temporal regions, mainly in the superior temporal sulcus (STS), in children with ASD. This hypoperfusion was individually detected in 83% of children with ASD. Finally, negative correlation was observed between ASD severity scores and rest CBF in the right posterior STS. Strikingly, despite the small sample studied here, our results are extremely similar to previous PET and SPECT findings describing decreased rest CBF in the same superior temporal regions at group and individual levels, as well as correlation with symptoms severity. The congruence between these results, with different methods and in different ASD profiles, reinforce the strength of rest functional abnormalities within these superior temporal regions in ASD and strongly indicates it might be a core characteristic of the disorder. Identifying a core dysfunctional region in ASD bears direct implications to the development of novel therapeutic interventions, such as transcranial magnetic stimulation. In addition, if confirmed in a larger sample, rest temporal hypoperfusion could become a reliable brain imaging biomarker in ASD.

Diversifying autism neuroimaging research: An arterial spin labeling review

“…The fixations of interest involved looking at characters eyes, a well-established surrogate for sociability in ASC (American Psychiatric Association, 2013). Essentially, both studies advocate that STS hypoperfusion affects social skills negatively in ASC (Saitovitch et al, 2016(Saitovitch et al, , 2019. Similarly, Yerys et al (2018) discovered a significant positive correlation between left fusiform gyrus perfusion and Benton facial recognition score, while correlation with ASC symptomatology was insignificant.…”

“…Out of the seven articles incorporated in Table 1, six studies compared ASC to NA and five of these studies found decreased CBF in ASC individuals. Saitovitch et al (2019) compared early adolescents and found significantly lower resting-state CBF in temporal regions, especially in the superior temporal sulcus (STS) using whole-brain voxelwise analysis. Congruently, Mori et al (2020)…”

“…Of the six studies comparing ASC to NA, four studies found only hypoperfusion in ASC (Mori et al, 2020;Saitovitch et al, 2019;Tang et al, 2022;Yerys et al, 2018), one study solitarily hyperperfusion (Peterson et al, 2019), and another study demonstrated both (Jann et al, 2015). However, the existing number of ASL studies is scarce, consequently at risk of being unrepresentative or misinterpreted.…”

Positron Emission Tomography in the Neuroimaging of Autism Spectrum Disorder

“…For task-state cerebral perfusion imaging, functional magnetic resonance such as arterial spin labeling (ASL) sequence has unique advantages [69]. Comparative studies or joint imaging with PET and fMRI will have a wider application in the future.…”

Positron Emission Tomography in the Neuroimaging of Autism Spectrum Disorder: A Review

“…For task-state cerebral perfusion imaging, functional magnetic resonance such as arterial spin labeling (ASL) sequence has unique advantages ( Saitovitch et al, 2019 ). In the future, joint imaging or comparative studies with PET and fMRI will have more widespread application prospects.…”