Basal ganglia and restricted and repetitive behaviours in Autism Spectrum Disorders: current status and future perspectives

Abstract

This Section of Epidemiology and Psychiatric Sciences appears in each issue of the Journal to stress the relevance of epidemiology for behavioural neurosciences, reporting the results of studies that explore the use of an epidemiological approach to provide a better understanding of the neural basis of major psychiatric disorders and, in turn, the utilisation of the behavioural neurosciences for promoting innovative epidemiological research.The ultimate aim is to help the translation of most relevant research findings into every-day clinical practice. These contributions are written in house by the journal's editorial team or commissioned by the Section Editor (no more than 1000 words, short unstructured abstract, four key-words, one Table or This editorial offers a concise overview of the recent structural magnetic resonance imaging studies that evaluate the basal ganglia (BG) volumes in autism spectrum disorders (ASD). The putative relationship between the repetitive or stereotyped behaviours of ASD and BG volumes is also explored, with a focus on possible translational approaches. Under the umbrella category of autism spectrum disorder (ASD) are included neurodevelopmental conditions with a high genetic and phenotypic heterogeneity, but shared by a symptom dyad: (1) deficits in social communication and interactions; and (2) repetitive patterns of behaviour, interests and activities (Diagnostic and Statistical Manual of Mental Disorders, DSM-5; American Psychiatric Association, 2013). The modifications of the diagnostic criteria included in the current version of DSM have enhanced the role of the second domain: in fact, the restricted and repetitive behaviours (RRB), once considered non-ASD specific and subordinate to the socio-communication deficit, are now required for an ASD diagnosis.Recent ASD research attempted to investigate whether the social communication and RRB dimensions are correlated with distinct endophenotypes and genotypes. In fact, a number of family studies in ASD have shown that genes controlling RRB are independent of genes controlling social or communication impairments (Mandy & Skuse, 2008

Pallidum and lateral ventricle volume enlargement in autism spectrum disorder

“…Though the findings for hippocampus and caudate volumes were only nominally significant despite the large cross sectional sample, they are consistent with the possible involvement of the caudate and hippocampus in ASD (Stanfield et al, 2008; Calderoni et al, 2014). Our finding of pallidum enlargement was not hypothesized based on studies published to date and warrants replication.…”

Network over‐connectivity differentiates autism spectrum disorder from other developmental disorders in toddlers: A diffusion MRI study

“…Higher FA values related to cingulum in ASD versus other-DD were also Bashat et al, 2007;Billeci et al, 2012;Weinstein et al, 2011]. Little evidence from DTI studies exists on the basal ganglia networks, even if volumetric MRI studies indicate those regions as presenting higher volumes and being related to repetitive symptoms of ASD [Calderoni et al, 2014]. Little evidence from DTI studies exists on the basal ganglia networks, even if volumetric MRI studies indicate those regions as presenting higher volumes and being related to repetitive symptoms of ASD [Calderoni et al, 2014].…”

“…This is not surprising as the cingulum is considered as a key region for socio-communicative skill development and its alteration in ASD has been widely reported also in older subjects [Ameis et al, 2013;Hoppenbrouwers et al, 2014;Ikuta et al, 2014]. Little evidence from DTI studies exists on the basal ganglia networks, even if volumetric MRI studies indicate those regions as presenting higher volumes and being related to repetitive symptoms of ASD [Calderoni et al, 2014]. Higher FA values have been detected within the putamen in adolescents [Cheng et al, 2010] and school-age children [Brito et al, 2009], while Langen et al [2012] found that adults with autism had a significantly smaller total brain white matter volume, lower fractional anisotropy of white matter tracts connecting putamen to frontal cortical areas, higher mean diffusivity of white matter tracts connecting accumbens to frontal cortex.…”

A systematic review of structural MRI biomarkers in autism spectrum disorder: A machine learning perspective

“…However the exact etiopathogenesis of ASD remains unclear, with predominant theories proposing genetic factors affecting cortical migration (Nickl‐Jockschat and Michel, 2011) and synaptic regulation (Takahashi et al, 2012), and altered developmental processes leading to both hypo‐ and hyper‐connectivity in different brain regions (Conti et al, 2017; Kana et al, 2014; Muller et al, 2011), specifically local over‐connectivity, long distance under connectivity (Wass, 2011), and excessive growth in several brain regions (Polšek et al, 2011). Consequently, there have been a wide range of structural brain regions implicated with ASD, most commonly that of early brain overgrowth and head circumference (Mosconi et al, 2009; Sacco et al, 2015), as well as more localised brain regions that may be associated with the social and motor impairments characteristic of ASD, including the frontal lobes, amygdala, cerebellum (Amaral et al, 2008; Li et al, 2017; Sivapalan and Aitchison, 2014), corpus callosum (Bellani et al, 2013; Hrdlicka, 2008; Stigler et al, 2011) and basal ganglia (Calderoni et al, 2014; Dougherty et al, 2016a). However, there has not yet been an agreement on structural changes in the brain that reflect these underlying mechanisms of ASD, limiting the utility of machine learning to provide accurate diagnoses of ASD and patient prognoses (Kassraian‐Fard et al, 2016).…”