Cerebellum最新文献

Background: Brain magnetic resonance imaging (MRI) often appears normal in patients with autoimmune cerebellar ataxia (ACA), whereas case studies indicate [¹⁸F]fluoro-2-deoxyglucose (FDG) positron emission tomography (PET) can detect abnormal metabolic patterns in these patients. This study aims to evaluate the brain FDG-PET characteristics of ACA, assess its clinical correlations and diagnostic utility.

Methods: 55 ACA patients and 28 age and sex-matched healthy controls were included. PET results were evaluated using both visual analysis and voxel-based analysis.

Results: Before immunotherapy, FDG-PET of ACA patients typically exhibited widespread hypermetabolism, while post-treatment scans showed cerebellar hypometabolism compared to healthy controls. Patients with encephalopathy were more likely to show abnormal metabolic activity in the cerebral cortex or hippocampus. Abnormal metabolic activity in the basal ganglia was more common in patients with extrapyramidal symptoms. Relative vermis hypermetabolism was observed in 40% of patients (22/55) and was significantly associated with a lower cerebrospinal fluid white blood cell count, higher cerebellar atrophy ratio, and cerebellar hypometabolism. Overall, the sensitivity of FDG-PET (85.5%) was significantly higher than that of MRI (39.1%, p < 0.001).

Conclusion: Our findings demonstrate that FDG-PET is more sensitive than MRI for detecting metabolic abnormalities in ACA patients. The metabolic differences between the cerebellar vermis and the hemispheres may suggest the vulnerability of the vermis in ACA. It also provides valuable clinical correlations, identifying patterns of hyper- and hypometabolism that align with specific neurological presentations.

Unertan Syndrome (UTS) is rare seen a typical autosomal-recessive inheritance disease in the world. This is the first study in the literature that examined physical functioning of subjects suffering from UTS in detail. Five quadrupedal subjects and one bipedal-ataxic subject are presented in this study. Neurological status, activities of daily living, and physical functioning of the cases were assessed. Their parents' level of influence was evaluated using the Impact on Family Scale. We examined all the cases in 2008 for the first time and in 2018 for final assessments. In the second visit in 2018, we found that all the cases had lower physical functioning and showed decreased independence in daily living activities. The quadrupedal subjects were still using quadrupedal gait pattern. We observed that their condition is getting worst as they get older. The parents reported that they influenced by their children's situation. The results obtained from this study showed that UTS affects physical functioning and independence in daily living activities of the subjects. UTS affects parents' lives negatively as well. Both UTS survivors and their parents should be included in an intensive rehabilitation program, including physiotherapy, ergotherapy, speech therapy, social support program, and psychotherapy to prevent health problems and to improve their quality of life.

Cerebellar ataxia (CA) is a heterogenous neurodegenerative disease affecting multiple neural structures. Individuals with CA exhibit difficulty coordinating voluntary movements and have a high prevalence of cough (dystussia) and swallowing (dysphagia) dysfunction. Although skill-based approaches to cough rehabilitation are efficacious for other neurogenerative diseases, the feasibility in CA remains unexplored. Seven people with genetically confirmed CA (6 female, 1 male) completed baseline voluntary cough assessments, followed by a single session of cough skill training (CST). Participants were instructed to cough with sufficient intensity to hit a target line set 25% above baseline maximum peak expiratory flow rate (PEFR). Metrics of feasibility included the percentage of trials completed, no adverse events, and duration of the treatment session. Bayesian multilevel models examined changes in three cough airflow outcomes: PEFR, cough expired volume (CEV), and cough inspired volume (CIV). All participants completed every trial of CST in less than one hour without any adverse events. PEFR improved by 0.77 L/s (95% CI: 0.37, 1.09) on single and 0.49 L/s (95% CI: 0.17, 0.76) on sequential voluntary cough. CEV increased by 0.36 L (95% CI: 0.11, 0.76) on single and 0.19 L (95% CI: 0.02, 0.46) on sequential voluntary cough. CIV showed no significant change. Individuals with CA demonstrated the ability to upregulate voluntary cough during a single session of CST within a manageable amount of time. These findings highlight the potential for modifiable cough outcomes in this population and support further research on the efficacy of CST in CA.

The cerebellum's role in language remains unclear, though cerebellar damage may influence expressive language via neurological or compensatory mechanisms. This study investigated the syntactic complexity of spoken language in individuals with dysarthria due to cerebellar ataxia. Speech samples were collected via a picture description task from 26 individuals with cerebellar ataxia and 28 age- and sex-matched controls. Two complete sentences from each participant's picture description were selected for analysis and categorized by the presence of dependent clauses. A novel syntactic complexity scoring system, based on the developmental acquisition of parts of speech and validated against Systematic Analysis of Language Transcripts (SALT) scoring, was used to analyze a total of 108 utterances. The novel complexity scores showed high correlation with SALT scores, supporting validity. While overall syntactic complexity was higher in control participants (Cohen's d = 0.39), the difference was not statistically significant (p = 0.057). However, when analyzed by clause type, controls produced significantly more complex utterances for both independent and dependent clauses. Individuals with ataxia also produced fewer dependent clauses overall. Within the ataxia group, syntactic complexity was not associated with dysarthria severity, naturalness ratings, dysarthria impact, age, or sex. This study suggests a potential contribution of cerebellar dysfunction to reduced expressive syntactic complexity, based on significant group differences observed in specific clause types. Although the overall group difference in syntactic complexity did not reach statistical significance, the results highlight patterns consistent with a cerebellar role in language formulation. This work also introduces and validates a new tool for quantifying syntactic complexity in connected speech, which may support future research in disordered language production.

Background: Spinocerebellar ataxia type 1 (SCA1) is characterised by motor and cognitive symptoms. Sex-specific differences in disease presentation and progression remain poorly understood. This study investigates the role of sex in clinical-demographic and motor/cognitive outcomes in SCA1.

Methods: This single-centre, longitudinal observational cohort study was conducted at the University Hospital of Ferrara between 2021 and 2024. Consecutively, genetically confirmed SCA1 patients were evaluated at baseline and after 24±6 months. Assessments included comprehensive neuropsychological testing and auditory event-related potentials (aERPs). Motor function was evaluated using the Scale for Assessment and Rating of Ataxia (SARA).

Results: Sixteen SCA1 patients (9 males, seven females) were evaluated at baseline, with 10 patients (5 males, five females) completing follow-up. Even if most cognitive functions were preserved in both sexes at baseline, males showed worse performance in emotion attribution tasks than females (42.8 ± 8.5 vs. 53.1 ± 5.7, r = 0.63). Over time, both sexes showed slightly worsening cognitive performance, although not statistically significant, with males demonstrating deficits in verbal fluency (p = 0.036) and emotion attribution (p = 0.048). In the same group, motor impairment worsened at follow-up, though not significantly. aERPs revealed no differences between sexes at follow-up.

Conclusion: Sex may influence cognitive outcomes in SCA1, with male patients showing greater vulnerability to cognitive decline. aERPs did not show significant modifications. These findings highlight the importance of considering sex-specific approaches in the clinical management of SCA1 patients and the higher values of a comprehensive neuropsychological assessment compared to the neurophysiological approach with aERPs to reach these slight changes over time.

Clinical trial number: Not applicable.

Background: Prism adaptation is used to study the cerebellar adaptive functions in neurological disorders. Previous papers reported that the number of prism exposure trials affected retention of the adaptation. However, it has not been studied how the trial number affects prism adaptation performances, especially its retention, in neurological disorders. Therefore, we aimed to investigate the relationship between exposure trial numbers and the acquisition of prism adaptation or the after-effects (AEs) (first and recovered) in patients with Parkinson's disease (PD), those with pure cerebellar-type spinocerebellar degeneration (SCD), and age-matched healthy volunteers (HVs).

Methods: Participants performed a finger-reaching task while wearing 20-D wedge-prism lenses, for 50 and 200 trials. The average of the errors in the last 10 prism exposure trials was considered an adaptation acquisition parameter. We also measured the first AE at the beginning of the post-exposure period and recovered AE by blocking visual feedback during the post-exposure period.

Results: In the HVs, 200 trials enlarged the recovered AE compared to 50 trials, without any effects on adaptation acquisition or the first AE. In the SCD group, 200 trials normalized the reduced adaptation and first AE of 50 trials, with similar enlargement of the recovered AE. In the PD group, neither the adaptation acquisition nor first AE was affected by the trial number, but the recovered AE was larger than that of the HVs in 50 trials. No prism adaptation parameters correlated with any clinical severity scores.

Conclusions: We first showed that 200 trials compensate for reduced prism adaptation owing to cerebellar dysfunction compared to 50 trials. In PD, 50 trials induced an increase of the recovered AE, which may reflect the cerebellar circuit hyperfunction to compensate for the basal-ganglia dysfunction.

Motor performance declines with age, particularly affecting reaction time and proactive response inhibition. While cortical influences on age-related motor decline are well-documented, the cerebellum's role remains unclear. Cerebellar Brain Inhibition (CBI), which can be measured through dual-site transcranial magnetic stimulation (TMS), may provide insights into age-related changes in motor control. We aimed to (1) compare resting-state CBI between young and older adults, (2) investigate the relationship between CBI and upper limb motor performance, and (3) examine whether this relationship differs between age groups. Using dual-site TMS, resting-state CBI was assessed in young and older adults. Motor performance was evaluated using a task battery measuring simple and choice reaction times, and response inhibition. As expected, older adults exhibited significantly longer reaction times and reduced reactive inhibition with lower accuracy compared to younger adults. No significant differences in resting CBI were observed between age groups, and no association was found between CBI and motor performance outcomes. Despite clear age-related differences in motor performance, resting CBI revealed no difference between age groups and showed no association with motor control measures. These findings suggest that the effect of aging on dual-site TMS-derived cerebellar inhibition at rest and its association with motor performance might be limited. However, age-related cerebellar effects on motor control might manifest during task execution rather than at rest, highlighting the potential importance of investigating CBI modulation during motor performance in the context of aging.