Limits...
Altered resting perfusion and functional connectivity of default mode network in youth with autism spectrum disorder.

Jann K, Hernandez LM, Beck-Pancer D, McCarron R, Smith RX, Dapretto M, Wang DJ - Brain Behav (2015)

Bottom Line: We found increased local FC in the anterior module of the default mode network (DMN) accompanied by decreased CBF in the same area.In our cohort, both alterations were associated with greater social impairments as assessed with the Social Responsiveness Scale (SRS-total T scores).Furthermore, there was reduced long-range FC between anterior and posterior modules of the DMN in children with ASD.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of FMRI Technology (LOFT), Ahmanson-Lovelace Brain Mapping Center, Department of Neurology, University of California Los Angeles, California.

ABSTRACT

Background: Neuroimaging studies can shed light on the neurobiological underpinnings of autism spectrum disorders (ASD). Studies of the resting brain have shown both altered baseline metabolism from PET/SPECT and altered functional connectivity (FC) of intrinsic brain networks based on resting-state fMRI. To date, however, no study has investigated these two physiological parameters of resting brain function jointly, or explored the relationship between these measures and ASD symptom severity.

Methods: Here, we used pseudo-continuous arterial spin labeling with 3D background-suppressed GRASE to assess resting cerebral blood flow (CBF) and FC in 17 youth with ASD and 22 matched typically developing (TD) children.

Results: A pattern of altered resting perfusion was found in ASD versus TD children including frontotemporal hyperperfusion and hypoperfusion in the dorsal anterior cingulate cortex. We found increased local FC in the anterior module of the default mode network (DMN) accompanied by decreased CBF in the same area. In our cohort, both alterations were associated with greater social impairments as assessed with the Social Responsiveness Scale (SRS-total T scores). While FC was correlated with CBF in TD children, this association between FC and baseline perfusion was disrupted in children with ASD. Furthermore, there was reduced long-range FC between anterior and posterior modules of the DMN in children with ASD.

Conclusion: Taken together, the findings of this study--the first to jointly assess resting CBF and FC in ASD--highlight new avenues for identifying novel imaging markers of ASD symptomatology.

No MeSH data available.


Related in: MedlinePlus

Associations between areas with hyperperfusion in autism spectrum disorders (ASD) and symptom severity scores. Spearman’s rank correlations between Social Responsiveness Scale (SRS)-total scores, respectively, Autism Diagnostic Observation Schedule (ADOS) severity scores to CBF (corrected for global GM-CBF and age). L-MTL: left middle temporal gyrus/L-MTL/IFO: left middle temporal gyrus/inferior frontal operculum/OFC: orbitofrontal cortex.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
getmorefigures.php?uid=PMC4589806&req=5

fig03: Associations between areas with hyperperfusion in autism spectrum disorders (ASD) and symptom severity scores. Spearman’s rank correlations between Social Responsiveness Scale (SRS)-total scores, respectively, Autism Diagnostic Observation Schedule (ADOS) severity scores to CBF (corrected for global GM-CBF and age). L-MTL: left middle temporal gyrus/L-MTL/IFO: left middle temporal gyrus/inferior frontal operculum/OFC: orbitofrontal cortex.

Mentions: Within the frontotemporal regions showing hyperperfusion in the ASD group (Fig.3), SRS-total T scores were positively correlated with CBF in the left middle temporal gyrus (r = 0.33 P < 0.05), inferior temporal gyrus (r = 0.34 P < 0.04), and inferior frontal operculum (r = 0.34 P < 0.04) within the whole cohort of ASD and TD children. These correlations with SRS-total T scores, however, did not reach significance when separating the individual ASD or TD groups, suggesting they might have been driven by group differences in social functioning. Finally, CBF in medial orbitofrontal cortex was positively correlated with ADOS severity scores in children with ASD (r = 0.49, P < 0.05). All above correlations survived correction of structural variations by including Jacobian determinant as a covariate.


Altered resting perfusion and functional connectivity of default mode network in youth with autism spectrum disorder.

Jann K, Hernandez LM, Beck-Pancer D, McCarron R, Smith RX, Dapretto M, Wang DJ - Brain Behav (2015)

Associations between areas with hyperperfusion in autism spectrum disorders (ASD) and symptom severity scores. Spearman’s rank correlations between Social Responsiveness Scale (SRS)-total scores, respectively, Autism Diagnostic Observation Schedule (ADOS) severity scores to CBF (corrected for global GM-CBF and age). L-MTL: left middle temporal gyrus/L-MTL/IFO: left middle temporal gyrus/inferior frontal operculum/OFC: orbitofrontal cortex.
© Copyright Policy - open-access
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4589806&req=5

fig03: Associations between areas with hyperperfusion in autism spectrum disorders (ASD) and symptom severity scores. Spearman’s rank correlations between Social Responsiveness Scale (SRS)-total scores, respectively, Autism Diagnostic Observation Schedule (ADOS) severity scores to CBF (corrected for global GM-CBF and age). L-MTL: left middle temporal gyrus/L-MTL/IFO: left middle temporal gyrus/inferior frontal operculum/OFC: orbitofrontal cortex.
Mentions: Within the frontotemporal regions showing hyperperfusion in the ASD group (Fig.3), SRS-total T scores were positively correlated with CBF in the left middle temporal gyrus (r = 0.33 P < 0.05), inferior temporal gyrus (r = 0.34 P < 0.04), and inferior frontal operculum (r = 0.34 P < 0.04) within the whole cohort of ASD and TD children. These correlations with SRS-total T scores, however, did not reach significance when separating the individual ASD or TD groups, suggesting they might have been driven by group differences in social functioning. Finally, CBF in medial orbitofrontal cortex was positively correlated with ADOS severity scores in children with ASD (r = 0.49, P < 0.05). All above correlations survived correction of structural variations by including Jacobian determinant as a covariate.

Bottom Line: We found increased local FC in the anterior module of the default mode network (DMN) accompanied by decreased CBF in the same area.In our cohort, both alterations were associated with greater social impairments as assessed with the Social Responsiveness Scale (SRS-total T scores).Furthermore, there was reduced long-range FC between anterior and posterior modules of the DMN in children with ASD.

View Article: PubMed Central - PubMed

Affiliation: Laboratory of FMRI Technology (LOFT), Ahmanson-Lovelace Brain Mapping Center, Department of Neurology, University of California Los Angeles, California.

ABSTRACT

Background: Neuroimaging studies can shed light on the neurobiological underpinnings of autism spectrum disorders (ASD). Studies of the resting brain have shown both altered baseline metabolism from PET/SPECT and altered functional connectivity (FC) of intrinsic brain networks based on resting-state fMRI. To date, however, no study has investigated these two physiological parameters of resting brain function jointly, or explored the relationship between these measures and ASD symptom severity.

Methods: Here, we used pseudo-continuous arterial spin labeling with 3D background-suppressed GRASE to assess resting cerebral blood flow (CBF) and FC in 17 youth with ASD and 22 matched typically developing (TD) children.

Results: A pattern of altered resting perfusion was found in ASD versus TD children including frontotemporal hyperperfusion and hypoperfusion in the dorsal anterior cingulate cortex. We found increased local FC in the anterior module of the default mode network (DMN) accompanied by decreased CBF in the same area. In our cohort, both alterations were associated with greater social impairments as assessed with the Social Responsiveness Scale (SRS-total T scores). While FC was correlated with CBF in TD children, this association between FC and baseline perfusion was disrupted in children with ASD. Furthermore, there was reduced long-range FC between anterior and posterior modules of the DMN in children with ASD.

Conclusion: Taken together, the findings of this study--the first to jointly assess resting CBF and FC in ASD--highlight new avenues for identifying novel imaging markers of ASD symptomatology.

No MeSH data available.


Related in: MedlinePlus