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Spinocerebellar ataxias type 2 (SCA2) is a rare genetic disorder characterised by the degeneration of the Cerebellum, its connections and many Brainstem areas. A voxel-based morphometry (VBM) analysis was performed on 12 genetically determined SCA2 patients and 31 controls, normalising the brains with two different atlases: one was created in-house with DARTEL (a diffeomorphic registration method) and the other was SUIT (an exclusive Cerebellum atlas). We administered two versions of a popular executive/planning functions test: the Tower of London, in the traditional and in a computerised version that does not require the use of hands, to correlate the regional atrophy with the tests' performances and to discover the different associations of Cerebellum's areas to cognitive dysfunctions. SCA2 showed a diffuse infratentorial atrophy with the whole Cerebellum and Brainstem affected, the overall patterns were highly overlapping between atlases with some minor differences. The DARTEL VBM also allowed detecting two sovratentorial clusters of atrophy, one in the left Inferior Parietal Lobule and the other in the Corticospinal Tracts. Additional analyses revealed a partial involvement of many White Matter tracts and of the Thalamus in the pathology. The classical Tower of London version correlated maximally with the right Lobule IV-V, when the computerised version correlated with the right Crus 1. The correlations of different versions of the test suggested a dissociation between the dysfunctions in SCA2: the Posterior Cerebellum was linked to the executive dysfunction while the Anterior Cerebellum was linked to the coordinative dysfunction.

Cerebellar agenesis is a rare disorder. We present the neurological and neuropsychological features of a patient with partial cerebellar agenesis (TZ), together with SPECT perfusion and fMRI activation during a finger tapping task. TZ shows only mild cerebellar signs, while neuropsychological testing discloses severe deficits in many domains, in accordance with the theorized role of the cerebellum in cognition. FMRI and SPECT demonstrate an activation and a symmetrical perfusion of the cerebellar remnants, that can be related to the residual cerebellar motor function. The left frontal and parieto-temporal cortex hypoperfusion can explain the severe cognitive impairment and could be linked to the abnormal cerebellar development.

Patients with cerebellar lesions present some affective and cognitive disorders, defining a peculiar pattern of cognitive impairment, so-called cerebellar cognitive affective syndrome. This pattern has been confirmed in many genotypes of spinocerebellar ataxias (SCA), a group of genetically defined pathologies characterized by the degeneration of the cerebellum and its connections. Recently, in SCA patients, some authors focused the interest on social cognition evidencing an impairment of theory of mind and basic emotion recognition by verbal material. The recognition of emotions in faces is an essential component of social cognition; therefore, we assessed this ability in SCA patients, expanding the study from the basic verbal emotions to the basic and social visual emotion recognition. We assessed facial emotion recognition using two basic and social emotion tasks in a group of SCA patients together with a complete clinical and neuropsychological evaluation. We compared results with the performance of a control group. We demonstrated a significant difference between patients and controls both in basic and social emotion recognition, although we found a specific impairment only for social emotions. The deficit was not correlated to clinical and demographic features. The cognitive and psychological profile did not explain the impairment in emotion recognition. This result supports the hypothesis that the impairment in social emotion recognition could be specifically related to a defect in the corticocerebellar network. [ABSTRACT FROM AUTHOR]

We administered a large battery of neuropsychological tests to an heterogeneous cohort of genetically defined spinocerebellar ataxia (SCA) patients in order to assess their cognitive profile and to compare cognitive impairment among different SCA genotypes, particularly between SCA with the classical pattern of olivo-ponto-cerebellar atrophy (SCA1 and SCA2) and those with a relatively 'pure' olivo-cerebellar atrophy (SCA6 and SCA8). Our data revealed a neuropsychological picture characterized by fronto-parietal involvement with mnestic, linguistic, visuospatial, attentional, executive, and mood changes, in agreement with the cerebellar cognitive affective syndrome definition. We found a homogeneous neuropsychological profile among SCA subgroups with a prominent role of frontal dysfunction-particularly, attention, memory, and executive functions. We analyzed the possible interactions between neuropsychological pattern and clinical, demographical, and genetic variables. We found the presence of a cognitive impairment at the early stages of the disease, without visuospatial alterations, which appeared later. Age and education represented the most important demographic factors to predict the neuropsychological performance in SCA and in controls, but their effect in patients had definitely more impact. In our sample education could represent a protective factor and a marker of an enriched environment or a better developmental cognitive differentiation. We demonstrated that in our patients there was a distinct subgroup of high functional subjects and that triplet repeats modulated the effect of aging on cognition and progression of motor disability. [ABSTRACT FROM AUTHOR]

Abstract: Recent studies focussing on neuroimaging features of eating disorders have observed that anorexia nervosa (AN) is characterized by significant grey matter (GM) atrophy in many brain regions, especially in the cerebellum and anterior cingulate cortex. To date, no studies have found GM atrophy in bulimia nervosa (BN) or have directly compared patients with AN and BN. We used voxel-based morphometry (VBM) to characterize brain abnormalities in AN and BN patients, comparing them with each other and with a control group, and correlating brain volume with clinical features. We recruited 17 AN, 13 BN and 14 healthy controls. All subjects underwent high-resolution magnetic resonance imaging (MRI) with a T1-weighted 3D image. VBM analysis was carried out with the FSL-VBM 4.1 tool. We found no global atrophy, but regional GM reduction in AN with respect to controls and BN in the cerebellum, fusiform area, supplementary motor area, and occipital cortex, and in the caudate in BN compared to AN and controls. Both groups of patients had a volumetric increase bilaterally in somatosensory regions with respect to controls, in areas that are typically involved in the sensory-motor integration of body stimuli and in mental representation of the body image. Our VBM study documented, for the first time in BN patients, the presence of volumetric alterations and replicated previous findings in AN patients. We evidenced morphological differences between AN and BN, demonstrating in the latter atrophy of the caudate nucleus, a region involved in reward mechanisms and processes of self-regulation, perhaps involved in the genesis of the binge-eating behaviors of this disorder. [Copyright &y& Elsevier]