The cerebellar topography of attention sub-components in spinocerebellar ataxia type 2

Abstract

Spinocerebellar ataxia type 2 (SCA2) is an autosomal dominant neurodegenerative disease characterized by a progressive cerebellar syndrome and multiple-domain cognitive impairments. The cerebellum is known to contribute to distinct functional networks related to higher-level functions. The aims of the present study were to investigate the different sub-components of attention and to analyse possible correlations between attention deficits and specific cerebellar regions in SCA2 patients. To this purpose, 11 SCA2 patients underwent an exhaustive attention battery that evaluated several attention sub-components. The SCA2 group performed below the normal range in tasks assessing selective attention, divided attention, and sustained attention, obtaining negative Z-scores. These results were confirmed by non-parametric Mann-Whitney U tests that showed significant differences between SCA2 and control subjects in the same sub-components of the attention battery, allowing us to speculate on cerebellar involvement when a high cognitive demand is required (i.e., multisensory integration, sequencing, prediction of events, and inhibition of inappropriate response behaviours). The voxel-based morphometry analysis showed a pattern of significantly reduced grey matter volume in specific cerebellar lobules. In particular, the SCA2 patients showed significant grey matter loss in bilateral regions of the anterior cerebellar hemisphere (IV) and in the posterior lobe (VI-IX) and posterior vermis (VI-IX). Statistical analysis found significant correlations between grey matter reductions in the VIIb/VIIIa cerebellar lobules and impairments in Sustained and Divided Attention tasks and between grey matter reduction in the vermal VI lobule and impairment in the Go/NoGo task. For the first time, the study demonstrated the involvement of specific cerebellar lobules in different sub-components of the attention domain, giving further support to the inclusion of the cerebellum within the attention network.

Cognitive inhibition impairments in presymptomatic C9orf72 carriers

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Functional Changes of Mentalizing Network in SCA2 Patients: Novel Insights into Understanding the Social Cerebellum

“…In recent years, an increasing body of studies focused on the cerebellar role in cognitive functions and emotional regulation also including social cognition abilities [1][2][3][4][5][6][7][8][9][10]. From an anatomical point of view, research documented the existence of reciprocal connections between specific cerebellar regions and associative and paralimbic cerebral structures related to emotional and social processing such as the temporo-parietal junction (TPJ), the lateral temporal cortex, the posterior cingulate cortex, the inferior frontal gyrus [11], the amygdala [12] and the insula [13].…”

Combination of structural MRI, functional MRI and brain PET-CT provide more diagnostic and prognostic value in patients of cerebellar ataxia associated with anti-Tr/DNER: a case report

“…Upon her re-admission 1 month later, the patient's major complaint was worsening of the ataxia and an increased cognitive-emotional deficit. In recent years, increasing evidence for a role for the cerebellum in emotion and cognition has emerged [8][9][10][11][12] and the patient was identified as having cerebellar cognitive affective syndrome [13]. The default mode network (DMN) has become the primary and most popular target of resting state networks and is thought to be involved in advanced cognitive functions and emotion [14][15][16].…”