Cerebellum最新文献

{"title":"The Cerebellar Cognitive Affective/Schmahmann Syndrome Scale: Updates and Insights.","authors":"Maia Hirsch, Brigitte Jacoby, Samantha Pierce, Jason MacMore, Jeremy D Schmahmann","doi":"10.1007/s12311-025-01890-3","DOIUrl":"10.1007/s12311-025-01890-3","url":null,"abstract":"<p><p>The Cerebellar Cognitive Affective / Schmahmann Syndrome scale (CCAS-S) detects cognitive and neuropsychiatric changes in cerebellar disease (CD). It has good sensitivity and specificity, but a false positive rate ~ 5%. We determined that healthy controls (HC) fail digit span tasks (DS) when presented with one repetition opportunity. We tested the hypothesis that providing participants a second attempt at DS would improve performance and decrease false positive rate. We also evaluated influence of age and education on CCAS-S scores. We administered the CCAS-S to 50 CD and 85 HC, providing a second attempt at forward / reverse DS for each failed number sequence, using either the same numbers, or a different set of numbers of the same length. Performance with same vs different digits was identical. After second DS attempt, raw score increased: HC, 106.1 ± 9.4 to 106.8 ± 9.2; CD, 89.2 ± 15.5 to 90.6 ± 15.8, and failed domains decreased: HC, 0.67 ± 0.89 to 0.4 ± 0.73; CD, 2.62 ± 1.9 to 2.24 ± 1.9. False positive definite CCAS (≥ 3 failed domains) decreased in HC, 4.7% to 1.2%. In CD, definite CCAS remained high, 48% to 38%. Some older HC failed ≥ 3 domains. Education (all ≥ 12 years) did not impact performance in HC; CD with more education failed fewer domains. False positive definite CCAS-S was reduced to 1.2% by second attempt at forward and backward DS. The CCAS-S detected incipient cognitive impairment in older individuals. Education effects were modest, but cohorts with education ≤ 11 years need further study.</p>","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"136"},"PeriodicalIF":2.4,"publicationDate":"2025-07-23","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144692322","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Activation of α2A-adrenergic Receptors Promotes Facial Sensory Stimulation-Evoked Cerebellar MLI-PC Long-Term Depression and Motor Learning in Vivo in Mice.","authors":"Wen-Cai Weng, Xu-Dong Zhang, Jun-Ya Wang, Ming-Ze Sun, Chao-Yue Chen, Xian-Hua Jin, De-Lai Qiu, Chun-Ping Chu","doi":"10.1007/s12311-025-01892-1","DOIUrl":"10.1007/s12311-025-01892-1","url":null,"abstract":"<p><p>The α2-adrenergic receptor (α2-AR) is involved in various forms of information transmission in the cerebellar cortex, but its role in modulating sensory stimulation-induced synaptic plasticity remains unclear. We investigated the role of the α2-AR in facial stimulation-evoked long-term synaptic plasticity within molecular layer interneuron-Purkinje cell (MLI-PC) circuitry in the cerebellum by electrophysiological, pharmacological and immunohistochemical methods, and used alongside the rotarod test to assess the impact of receptor activity on motor learning in mice. Facial stimulation at 1 Hz induced MLI-PC long-term depression (LTD), which was significantly enhanced by microinjection of noradrenaline (NA) into the cerebellar molecular layer. Blockade of the NMDA receptor abolished facial stimulation-induced MLI-PC LTD; However, the effect could be triggered in the absence of NMDA activity through NA or UK14304 α2-AR activation with concurrent stimulation. In the absence of NMDA receptor activity, α2-AR-mediated facial stimulation-induced MLI-PC LTD was abolished by blockade of α2A-, but not α2B- or α2C-ARs. Facial stimulation-induced MLI-PC LTD was triggered by a selective α2A-AR agonist, guanfacine, but it was completely prevented by inhibition of protein kinase A (PKA) activity with KT5720. The rotarod test indicated that microinjection of guanfacine into the cerebellar cortex to activate α2A-ARs significantly improved early motor learning. Immunochemistry revealed α2A-AR immunoreactivity throughout the mouse cerebellar cortex, mostly in the PC layer and MLIs. These results suggest that NA facilitates facial stimulation-induced, α2A-AR/PKA signaling cascade-dependent MLI-PC LTD and promotes the acquisition of motor learning in mice.</p>","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"135"},"PeriodicalIF":2.4,"publicationDate":"2025-07-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144676395","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"The Natural History Study and Biomarker Collection of the Clinical Research Consortium for the Study of Cerebellar Ataxia (CRC-SCA).","authors":"Yicheng Lin, Nadia Amokrane, Sandie Worley, Lauren R Moore, Andrew Rosen, Laura P Crespo, Kelsey Trace, Tetsuo Ashizawa, Andrew Billnitzer, Susan Perlman, Aaron Fisher, Khalaf Bushara, Michael D Geschwind, Cameron Dietiker, Christopher M Gomez, Mahesh Padmanaban, Puneet Opal, Rizwan S Akhtar, Henry Paulson, Sharan Srinivasan, Amy Ferng, Frank Ferrari, Chiadi U Onyike, Ann Fishman, Sarah Ying, Ashley Paul, Jeremy D Schmahmann, Christopher D Stephen, Anoopum Gupta, Chih-Chun Lin, S H Subramony, Matthew Burns, George Wilmot, Antoine Duquette, Theresa Zesiewicz, Marie Y Davis, Ali G Hamedani, Joaquin A Vizcarra, Stefan M Pulst, Sharon Primeaux, Gülin Öz, Vikram G Shakkottai, Liana S Rosenthal, Sheng-Han Kuo","doi":"10.1007/s12311-025-01885-0","DOIUrl":"10.1007/s12311-025-01885-0","url":null,"abstract":"<p><p>Hereditary ataxias are progressive neurodegenerative disorders primarily affecting the cerebellum. Since 2009, the Clinical Research Consortium for the Study of Cerebellar Ataxias (CRC-SCA) has studied the natural history of common types of spinocerebellar ataxias (SCAs). The CRC-SCA is a 17-site academic collaboration supported by the National Ataxia Foundation. In 2024, the CRC-SCA expanded its scope by incorporating newly identified late-onset ataxias, including repeat expansion mutations in RFC1 and FGF14 causing Cerebellar Ataxia with Neuropathy and Vestibular Areflexia Syndrome (CANVAS) and SCA27B, respectively. These ongoing efforts have enriched the understanding of disease progression and facilitated access to biofluid and neuroimaging data for biomarker discovery, setting the stage for therapeutic development in hereditary ataxias. The CRC-SCA's natural history study and biomarker collection have validated several clinical outcome assessments (COAs) to capture important aspects of hereditary ataxias. We have also developed new COAs for cognitive and patient-reported outcome measures. A key component of the study includes biofluid collection-cerebrospinal fluid, plasma, and serum-to identify molecular biomarkers for disease progression and therapeutic response. Additionally, an incorporated magnetic resonance imaging (MRI) substudy provides critical imaging biomarkers, enhancing our ability to track macro- and microstructural, chemical and functional changes in the cerebellum and relate these to clinical presentations. The comprehensive, longitudinal dataset comprising COAs, biofluid biomarkers, and neuroimaging enhances clinical trial readiness in the field and accelerates therapeutic advancements for hereditary ataxias. This review highlights the collective efforts of CRC-SCA, details the study protocol, and emphasizes the integrity and specificity of the collected data elements.</p>","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"134"},"PeriodicalIF":2.4,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144660982","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Spinocerebellar Ataxia Type 27B can be Suspected Based on Clinical Phenotype: The Massachusetts General Hospital Ataxia Center Experience.","authors":"Leigh A Rettenmaier, Jin Yun Helen Chen, Jason MacMore, Anoopum S Gupta, Chih-Chun Lin, Christopher D Stephen, David Pellerin, Bernard Brais, Jeremy D Schmahmann","doi":"10.1007/s12311-025-01882-3","DOIUrl":"10.1007/s12311-025-01882-3","url":null,"abstract":"<p><p>Spinocerebellar Ataxia type 27B (SCA27B) is caused by an intronic GAA repeat expansion in the fibroblast growth factor 14 (FGF14) gene. The core clinical phenotype is a slowly progressive, adult-onset cerebellar ataxia, often with downbeat nystagmus (DBN) and episodic worsening. We tested whether clinical phenotyping could predict this genetic disorder. We screened the Massachusetts General Hospital Ataxia Center registry (n = 3,182) for patients with a) isolated DBN, b) DBN with ataxia, and c) autosomal dominant cerebellar ataxia (ADCA) that had eluded genetic diagnosis. Patient histories, examinations, and imaging were reviewed. Genetic analysis for FGF14 expansion was performed. Of 65 identified patients, 39 completed genetic testing. Among 14 with isolated DBN, 9 carried an FGF14 repeat expansion (GAA)_≥250 (range, 295-461), 1 had a potentially pathogenic allele (247 repeats), and 4 had normal alleles. Among 19 with DBN plus ataxia, 12 tested positive (276-431 repeats), 1 had a suspected pathogenic allele (228 repeats), and 6 had normal alleles. All 4 ADCA patients tested positive (320-483 repeats), as did 2 presymptomatic siblings. Our cohort enriched for suspicion of SCA27B had confirmed or suspected pathogenic FGF14-GAA expansion in 74.4% (29/39). Diagnostic success rate was 90.0% (27/30) in patients with onset > 45 years: 25/30 (GAA)_≥250, 2/30 (GAA)_200-249. Cerebellar atrophy was seen in 97.1% (34/35), mostly in the vermis/paravermis. Clinically meaningful improvement with 4-aminopyridine occurred in 71.0% (22/31) of patients. SCA27B can be reliably recognized from its core clinical phenotype in up to 90% of cases, enabling successful pharmacotherapy in 71.0%.</p>","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"133"},"PeriodicalIF":2.4,"publicationDate":"2025-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144660981","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Specific Contribution of the Cerebellar Inferior Posterior Lobe to Motor Learning in Degenerative Cerebellar Ataxia.","authors":"Kyota Bando, Takeru Honda, Kinya Ishikawa, Shinichi Shirai, Ichiro Yabe, Tomohiko Ishihara, Osamu Onodera, Yuichi Higashiyama, Fumiaki Tanaka, Yoshiyuki Kishimoto, Masahisa Katsuno, Takahiro Shimizu, Ritsuko Hanajima, Takumi Kanata, Yuji Takahashi, Hidehiro MizusawaMD","doi":"10.1007/s12311-025-01887-y","DOIUrl":"10.1007/s12311-025-01887-y","url":null,"abstract":"<p><strong>Background and objective: </strong>Degenerative cerebellar ataxia, a group of progressive neurodegenerative disorders, is characterised by cerebellar atrophy and impaired motor learning. Using CerebNet, a deep learning algorithm for cerebellar segmentation, this study investigated the relationship between cerebellar subregion volumes and motor learning ability.</p><p><strong>Methods: </strong>We analysed data from 37 patients with degenerative cerebellar ataxia and 18 healthy controls. Using CerebNet, we segmented four cerebellar subregions: the anterior lobe, superior posterior lobe, inferior posterior lobe, and vermis. Regression analyses examined the associations between cerebellar volumes and motor learning performance (adaptation index [AI]) and ataxia severity (Scale for Assessment and Rating of Ataxia [SARA]).</p><p><strong>Results: </strong>The inferior posterior lobe volume showed a significant positive association with AI in both single (B = 0.09; 95% CI: [0.03, 0.16]) and multiple linear regression analyses (B = 0.11; 95% CI: [0.008, 0.20]), an association that was particularly evident in the pure cerebellar ataxia subgroup. SARA scores correlated with anterior lobe, superior posterior lobe, and vermis volumes in single linear regression analyses, but these associations were not maintained in multiple linear regression analyses. This selective association suggests a specialised role for the inferior posterior lobe in motor learning processes.</p><p><strong>Conclusion: </strong>This study reveals the inferior posterior lobe's distinct role in motor learning in patients with degenerative cerebellar ataxia, advancing our understanding of cerebellar function and potentially informing targeted rehabilitation approaches. Our findings highlight the value of advanced imaging technologies in understanding structure-function relationships in cerebellar disorders.</p>","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"132"},"PeriodicalIF":2.4,"publicationDate":"2025-07-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144644074","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"FDG-PET in Autoimmune Cerebellar Ataxia: Clinical Correlation and Diagnostic Superiority Over MRI.","authors":"Mange Liu, Qijun Li, Guangjuan Mao, Yicheng Zhu, Ruixue Cui, Hongzhi Guan","doi":"10.1007/s12311-025-01888-x","DOIUrl":"10.1007/s12311-025-01888-x","url":null,"abstract":"<p><strong>Background: </strong>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.</p><p><strong>Methods: </strong>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.</p><p><strong>Results: </strong>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).</p><p><strong>Conclusion: </strong>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.</p>","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"130"},"PeriodicalIF":2.4,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144621092","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Functional Assessment of the Subjects with Unertan Syndrome: 10 Years Follow-Up Study.","authors":"Halil Hakan Uysal, Hasan Hallaceli, Ugur Cavlak, Esra Dogru Huzmeli","doi":"10.1007/s12311-025-01883-2","DOIUrl":"10.1007/s12311-025-01883-2","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"131"},"PeriodicalIF":2.4,"publicationDate":"2025-07-12","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144621093","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Single-Session Feasibility of Cough Skill Training in Cerebellar Ataxia.","authors":"James C Borders, Sheng-Han Kuo, Michelle S Troche","doi":"10.1007/s12311-025-01884-1","DOIUrl":"10.1007/s12311-025-01884-1","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"129"},"PeriodicalIF":2.4,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144610178","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"False Beliefs, True Deficits: Investigating Social Cognition in Friedreich Ataxia.","authors":"Elien Heleven, Martin Vyhnalek, Simona Karamazovová, Frank Van Overwalle, Gilles Naeije","doi":"10.1007/s12311-025-01886-z","DOIUrl":"10.1007/s12311-025-01886-z","url":null,"abstract":"","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"128"},"PeriodicalIF":2.4,"publicationDate":"2025-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144610177","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Revisiting the Cerebellum's Linguistic Role: Evidence for Cerebellar Involvement in Expressive Syntax.","authors":"Melanie Esver, Caitlin Cloud, Allison Hilger, Christine Brennan","doi":"10.1007/s12311-025-01879-y","DOIUrl":"10.1007/s12311-025-01879-y","url":null,"abstract":"<p><p>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.</p>","PeriodicalId":50706,"journal":{"name":"Cerebellum","volume":"24 5","pages":"126"},"PeriodicalIF":2.4,"publicationDate":"2025-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12245948/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144602168","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":3,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}