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Resting-State Functional Connectivity Changes Between Dentate Nucleus and Cortical Social Brain Regions in Autism Spectrum Disorders

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Autism spectrum disorders (ASDs) are known to be characterized by restricted and repetitive behaviors and interests and by impairments in social communication and interactions mainly including “theory of mind” (ToM) processes. The cerebellum has emerged as one of the brain regions affected by ASDs. As the cerebellum is known to influence cerebral cortex activity via cerebello-thalamo-cortical (CTC) circuits, it has been proposed that cerebello-cortical “disconnection” could in part underlie autistic symptoms. We used resting-state (RS) functional magnetic resonance imaging (fMRI) to investigate the potential RS connectivity changes between the cerebellar dentate nucleus (DN) and the CTC circuit targets, that may contribute to ASD pathophysiology. When comparing ASD patients to controls, we found decreased connectivity between the left DN and cerebral regions known to be components of the ToM network and the default mode network, implicated in specific aspects of mentalizing, social cognition processing, and higher order emotional processes. Further, a pattern of overconnectivity was also detected between the left DN and the supramodal cerebellar lobules associated with the default mode network. The presented RS-fMRI data provide evidence that functional connectivity (FC) between the dentate nucleus and the cerebral cortex is altered in ASD patients. This suggests that the dysfunction reported within the cerebral cortical network, typically related to social features of ASDs, may be at least partially related to an impaired interaction between cerebellum and key cortical social brain regions.
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ORIGINAL PAPER
Resting-State Functional Connectivity Changes Between Dentate
Nucleus and Cortical Social Brain Regions in Autism Spectrum
Disorders
Giusy Olivito
1,2
&Silvia Clausi
1,2
&Fiorenzo Laghi
3
&Anna Maria Tedesco
1,2
&
Roberto Baiocco
3
&Chiara Mastropasqua
4
&Marco Molinari
5
&Mara Cercignani
4,6
&
Marco Bozzali
4
&Maria Leggio
1,2
Published online: 1 June 2016
#Springer Science+Business Media New York 2016
Abstract Autism spectrum disorders (ASDs) are known to be
characterized by restricted and repetitive behaviors and inter-
ests and by impairments in social communication and interac-
tions mainly including Btheory of mind^(ToM) processes.
The cerebellum has emerged as one of the brain regions af-
fected by ASDs. As the cerebellum is known to influence
cerebral cortex activity via cerebello-thalamo-cortical (CTC)
circuits, it has been proposed that cerebello-cortical
Bdisconnection^could in part underlie autistic symptoms.
We used resting-state (RS) functional magnetic resonance im-
aging (fMRI) to investigate the potential RS connectivity
changes between the cerebellar dentate nucleus (DN) and
the CTC circuit targets, that may contribute to ASD patho-
physiology. When comparing ASD patients to controls, we
found decreased connectivity between the left DN and cere-
bral regions known to be components of the ToM network and
the default mode network, implicated in specific aspects of
mentalizing, social cognition processing, and higher order
emotional processes. Further, a pattern of overconnectivity
was also detected between the left DN and the supramodal
cerebellar lobules associated with the default mode network.
The presented RS-fMRI data provide evidence that functional
connectivity (FC) between the dentate nucleus and the cere-
bral cortex is altered in ASD patients. This suggests that the
dysfunction reported within the cerebral cortical network, typ-
ically related to social features of ASDs, may be at least par-
tially related to an impaired interaction between cerebellum
and key cortical social brain regions.
Keywords Cerebellum .Cerebral cortex .Default mode
network .Social cognition .Theory of mind
Introduction
Autism spectrum disorders (ASDs) are neurodevelopmental
conditions mainly characterized by core deficits in social
communication and interaction, as well as the presence of
restricted and repetitive behaviors and interests [1]. It has
been proposed that ASDsdeficits can be explained by
individualsdifficulties with Btheory of mind^(ToM) pro-
cesses, a crucial component of social behavior referring to
the ability of attributing mental states to self and other in
order to predict and explain behaviors [2,3]. According to
the ToM hypothesis, pragmatic impairments of language
and communication typically observed in ASDs may be
explained in terms of social behavior deficits. The theory
that individuals with ASD are unable to represent mental
states shed light on the nature of social communication
impairments, assuming that a specific communication
*Maria Leggio
maria.leggio@uniroma1.it
1
Ataxia Laboratory, IRCCS Santa Lucia Foundation, Via Ardeatina
306, 00179 Rome, Italy
2
Department of Psychology, BSapienza^University of Rome, Via dei
Marsi 78, 00185 Rome, Italy
3
Department of Developmental and Social Psychology, Faculty of
Medicine and Psychology, BSapienza^University of Rome, Via dei
Marsi 78, 00185 Rome, Italy
4
Neuroimaging Laboratory, IRCCS Santa Lucia Foundation, Via
Ardeatina 306, 00179 Rome, Italy
5
Neurological and Spinal Cord Injury Rehabilitation Department A,
IRCCS Santa Lucia Foundation, Via Ardeatina 306,
00179 Rome, Italy
6
Clinical Imaging Sciences Centre, Brighton and Sussex Medical
School, University of Sussex, Falmer, BN1 9RR Brighton, UK
Cerebellum (2017) 16:283292
DOI 10.1007/s12311-016-0795-8
Content courtesy of Springer Nature, terms of use apply. Rights reserved.
... Functional connectivity has been used vastly in ASD studies. These studies show changes in functional connectivity in ASD (Di Martino et al., 2008;Smith et al., 2013;von dem Hagen et al., 2013;Ray et al., 2014;Tyszka et al., 2014;Uddin et al., 2015;Olivito et al., 2016;Hull et al., 2017;Guo et al., 2019;Bathelt and Geurts, 2020). A brain region or network can be both under-connected with some areas and simultaneously over-connected with other areas in ASDs compared to healthy controls (HCs; Just et al., 2004;Cherkassky et al., 2006;Kennedy et al., 2006;Assaf et al., 2010;Jones et al., 2010;Weng et al., 2010;Di Martino et al., 2011;Delmonte et al., 2013;Keown et al., 2013;Redcay et al., 2013;Nebel et al., 2014;Cerliani et al., 2015;Chien et al., 2015;Holiga et al., 2019). ...
... DMN, one of the restingstate networks, is active when the brain is in the resting state but deactivates during cognitive tasks or goal-directed behaviors (Raichle and Synder, 2007;Washington et al., 2014). According to different studies, under-connectivity and over-connectivity of DMN have been seen in ASD (Kennedy et al., 2006;Kennedy and Courchesne, 2008;Monk et al., 2009;Assaf et al., 2010;Weng et al., 2010;Wiggins et al., 2011;Jung et al., 2014;Yerys et al., 2015;Lee et al., 2016;Olivito et al., 2016;Padmanabhan et al., 2017). DMN changes are more consistent findings in autistic individuals. ...
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Cognitive functions are directly related to interactions between the brain's functional networks. This functional organization changes in the autism spectrum disorder (ASD). However, the heterogeneous nature of autism brings inconsistency in the findings, and specific pattern of changes based on the cognitive theories of ASD still requires to be well-understood. In this study, we hypothesized that the theory of mind (ToM), and the weak central coherence theory must follow an alteration pattern in the network level of functional interactions. The main aim is to understand this pattern by evaluating interactions between all the brain functional networks. Moreover, the association between the significantly altered interactions and cognitive dysfunctions in autism is also investigated. We used resting-state fMRI data of 106 subjects (5–14 years, 46 ASD: five female, 60 HC: 18 female) to define the brain functional networks. Functional networks were calculated by applying four parcellation masks and their interactions were estimated using Pearson's correlation between pairs of them. Subsequently, for each mask, a graph was formed based on the connectome of interactions. Then, the local and global parameters of the graph were calculated. Finally, statistical analysis was performed using a two-sample t -test to highlight the significant differences between autistic and healthy control groups. Our corrected results show significant changes in the interaction of default mode, sensorimotor, visuospatial, visual, and language networks with other functional networks that can support the main cognitive theories of autism. We hope this finding sheds light on a better understanding of the neural underpinning of autism.
... Consistent with these data, altered cerebellocerebral functional connectivity has been reported in adults with autism spectrum disorder (Olivito et al. 2017a, a neurodevelopmental disorder typically characterized by an impairment in social mentalizing (Baron-Cohen 1995;Hill and Frith 2003). In particular, altered FC was found between the cerebellar Crus II and cortical . ...
... Further support for this idea has been derived from resting-state functional connectivity studies in individuals with ASD that reported reduced functional connectivity between specific regions in the posterior cerebellum and regions in the "social brain" relevant for social interaction. Indeed, low resting-state functional connectivity between the Crus II and the TPJ adjacent to the STS (Igelström et al. 2017) and altered functional connectivity between the dentate nucleus and the cortical regions involved in social cognition were reported in adults with ASD (Olivito et al. 2017a. Accordingly, a recent study in ASD showed that more severe scores on the Autism Diagnostic Observation Schedule were associated with the degree of hypo-connectivity between Crus I/II and lobule IX and brain areas involved in language, emotional and social domains, including the bilateral STS, inferior frontal gyrus, amygdala and specific nodes in the default mode network (Arnold Anteraper et al. 2019). ...
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... According to earlier research, the corticocerebellocortical loops provide the structural basis for the behaviorally-regulating functional networks of executive, salience, default mode, dorsal attentional, and motor [34][35][36][37]. So far, the disrupted interactions of the cerebral-cerebellum have been observed in many neurological disorders such as autism spectrum disorders, Parkinson's disease, Alzheimer's disease, and frontotemporal dementia [38][39][40]. These investigations support the existence In these comparisons, two sample t test after a generalized linear model (GLM) with age, sex, and resting state microstate parameters regressed out. ...
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... The 3xTg-AD cerebellar nuclei show a gradient of neural loss through the mediolateral axis, with the fastigial nucleus being the most affected area, followed by the interpositus nucleus, and the Lat not being affected. [360,361] Autism spectrum disorders (ASD) [362,363] Content courtesy of Springer Nature, terms of use apply. Rights reserved. ...
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... described as involved in the pathogenesis of psychiatric disorders (i.e., schizophrenia) and neurodevelopmental conditions (i.e., autism spectrum disorders) characterized by social behavior difficulties 77,78 . Structural and functional cerebellar alterations have been reported in these conditions 77,[79][80][81] . In line with this, knowing more about the cerebellar tDCS-induced changes in mental state recognition ability would aid in developing new therapeutic protocols in these patient populations 82 . ...
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... Subjects affected by ASD had decreased white matter in the dentato-rubro-thalamic tract [470] and lower FA of the superior [471,472] and medial cerebellar peduncle [473][474][475]. Accordingly, patients with ASD had decreased functional connectivity between various parts of the cerebellar cortex and nuclei and different cortical regions [476][477][478][479][480], which may suggest an important cerebellar role in the pathophysiology of ASD. Like in schizophrenia, ASD was not only associated with reduced connectivity of particular projections, but also with increased strength of others [480][481][482][483]. ...
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... 11,13 Recent studies have suggested that the cerebello-cerebral neural network, involving lateral portions of the cerebellar hemispheres, the semilunar and posterior quadrangular lobules, is involved in higher brain functions. [18][19][20][21][22][23][24][25] In addition, autism is also associated with focal abnormalities in the cerebellum, especially in the semilunar lobule, [26][27][28][29][30][31][32] where cerebellar tubers occurred most commonly in this study. In patients with TSC, the strong correlation between cerebral tubers and ASD has been reported 13,33-36 ; however, the relationship between cerebellar tubers and autism has not been fully established. ...
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Chapter
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Chapter
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Cerebral cortical intrinsic connectivity networks share topographically arranged functional connectivity with the cerebellum. However, the contribution of cerebellar nodes to distributed network organization and function remains poorly understood. In humans, we applied theta-burst transcranial magnetic stimulation, guided by subject-specific connectivity, to regions of the cerebellum to evaluate the functional relevance of connections between cerebellar and cerebral cortical nodes in different networks. We demonstrate that changing activity in the human lateral cerebellar Crus I/II modulates the cerebral default mode network, whereas vermal lobule VII stimulation influences the cerebral dorsal attention system. These results provide novel insights into the distributed, but anatomically specific, modulatory impact of cerebellar effects on large-scale neural network function.
Conference Paper
Background: ASD is associated with disturbances of neural connectivity. Connectivity is typically examined within the context of a cognitive task. However, connectivity also exists in the absence of a task. This intrinsic connectivity, known as resting-state connectivity is particularly active in a set of structures called the default network, which includes the posterior cingulate cortex (PCC), retro-splenial cortex, lateral parietal cortex/angular gyrus, medial prefrontal cortex, superior frontal gyrus, temporal lobe, and parahippocampal gyrus. Exploring resting-state connectivity in ASD is of interest as these networks might be active during self-referencing and introspection, domains in which deficits in empathy and social cognition hinge upon. In addition, no prior study has explored resting-state connectivity within adolescents with ASD. Objectives: We sought to examine resting-state connectivity within the default network in adolescents with ASD and to examine how various measures of symptom severity and adaptive functioning relate to patterns of connectivity. Following the results from a previous resting connectivity study in our lab that showed patterns of weaker and tighter connectivity in adults with ASD, we hypothesized that adolescents with ASD would show weaker coupling between the PCC and the superior frontal gyrus relative to controls. Second, we hypothesized that adolescents with ASD would show tighter coupling between the PCC and the superior temporal gyrus and parahippocampal gyrus relative to controls. Finally, in an exploratory analysis we sought to examine if symptom severity was associated strength of connectivity. Methods: 12 adolescents with ASD and 12 age-matched controls between the ages of 13-17 took part in a functional MRI study. Participants were instructed to “let your mind wander freely” while looking at a fixation cross displayed in the middle of the screen for 10 minutes during fMRI acquisition. A seed region was placed in the PCC and functional connectivity was examined by obtaining the correlational activity between the PCC and other areas of the default network. Results: Both ASD and control groups activated the default network of the brain at p<0.05 (whole brain corrected). Analyses of group differences revealed that individuals with ASD relative to controls showed weaker connectivity between the PCC and all regions in the default network (p<0.05 small volume corrected). Moreover, ASD relative to the control groups showed tighter connectivity between the PCC and the superior temporal gyrus. A correlation analysis revealed that poorer social functioning was associated with weaker connectivity between the PCC and left angular gyrus. Greater impairments in the restricted and repetitive behavior domain were associated with weaker connectivity between the PCC and the temporal lobe. Finally, lower overall adaptive functioning in the ASD group was associated with weaker connectivity between the PCC and the angular gyrus. Conclusions: Relative to the control group, the ASD group showed weaker functional connectivity within the default network in the absence of a task. In addition, more severe symptoms were associated with weaker connectivity within the default network. These findings suggest evidence for altered connectivity within the default network and that connectivity between these structures is associated with core impairments in ASD.