Gender may be related to the side of the motor syndrome and cognition in idiopathic Parkinson's disease.

BACKGROUND: and Sex and cognitive profile may be related to the laterality of motor symptoms in idiopathic Parkinson's disease. INTRODUCTION: Parkinson's disease (PD) is well recognised as an inherently asymmetric disease with unilateral onset of motor symptoms. The laterality of motor symptoms may be linked to sex, clinical and demographic variables, and neuropsychological disorders. However, the available data are inconsistent. This study aimed to explore the potential association between the laterality of motor symptoms and clinical and demographic variables and deficits in specific cognitive domains. MATERIAL AND METHODS: We retrospectively recruited 97 participants with idiopathic PD without dementia; 60 presented motor symptoms on the left side and 37 on the right side. Both groups were comparable in terms of age, age at disease onset, disease duration, and severity of the neurological deficits according to the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr scale. RESULTS: Participants with left-side motor symptoms scored lower on the Schwab and England Activities of Daily Living scale. Our sample included more men than women (67% vs. 33%). Both sexes were not equally represented in the 2 groups: there were significantly more men than women in the group of patients with left-side motor symptoms (77% vs. 23%), whereas the percentages of men and women in the group of patients with right-side motor symptoms were similar (51% vs. 49%). Both groups performed similarly in all neuropsychological tasks, but women, independently of laterality, performed better than men in the naming task. CONCLUSION: We found a clear prevalence of men in the group of patients with left-side motor symptoms; this group also scored lower on the Schwab and England Scale. Female sex was predictive of better performance in the naming task. Sex should always be considered in disorders that cause asymmetric involvement of the brain, such as PD.

Gender may be related to the side of the motor syndrome and cognition in idiopathic Parkinson's disease / Posible relación entre sexo y perfil cognitivo y la lateralidad de los síntomas motores en la enfermedad de Parkinson idiopática

Background: and Sex and cognitive profile may be related to the laterality of motor symptoms in idiopathic Parkinson's disease. Introduction: Parkinson's disease (PD) is well recognised as an inherently asymmetric disease with unilateral onset of motor symptoms. The laterality of motor symptoms may be linked to sex, clinical and demographic variables, and neuropsychological disorders. However, the available data are inconsistent. This study aimed to explore the potential association between the laterality of motor symptoms and clinical and demographic variables and deficits in specific cognitive domains. Material and methods: We retrospectively recruited 97 participants with idiopathic PD without dementia; 60 presented motor symptoms on the left side and 37 on the right side. Both groups were comparable in terms of age, age at disease onset, disease duration, and severity of the neurological deficits according to the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr scale. Results: Participants with left-side motor symptoms scored lower on the Schwab and England Activities of Daily Living scale. Our sample included more men than women (67% vs. 33%). Both sexes were not equally represented in the 2 groups: there were significantly more men than women in the group of patients with left-side motor symptoms (77% vs. 23%), whereas the percentages of men and women in the group of patients with right-side motor symptoms were similar (51% vs. 49%). Both groups performed similarly in all neuropsychological tasks, but women, independently of laterality, performed better than men in the naming task. Conclusion: We found a clear prevalence of men in the group of patients with left-side motor symptoms; this group also scored lower on the Schwab and England Scale. Female sex was predictive of better performance in the naming task. Sex should always be considered in disorders that cause asymmetric involvement of the brain, such as PD.(AU)

Introducción: La enfermedad de Parkinson (EP) es una enfermedad asimétrica en la que los primeros síntomas se presentan solo en un lado del cuerpo. El lado de inicio de la sintomatología puede depender del sexo, de variables clínicas y demográficas y de la presencia de trastornos neuropsicológicos. Sin embargo, la evidencia disponible no es consistente. Nuestro estudio pretende determinar si el lado que presenta síntomas motores tiene alguna relación con variables clínicas y demográficas y con déficits en determinados dominios cognitivos. Materiales y métodos: Incluimos 97 individuos con EP y sin demencia; 60 de ellos tenían síntomas motores en el lado izquierdo y 37 en el lado derecho. Ambos grupos presentaban similitudes en cuanto a edad, edad de inicio de la enfermedad, duración de la enfermedad, y gravedad de los síntomas neurológicos, según la Unified Parkinson's Disease Rating Scale y la Hoehn and Yahr Scale. Resultados: Los participantes con síntomas en el lado izquierdo obtuvieron puntuaciones más bajas en la Escala de Actividades de la Vida Diaria de Schwab y England. Nuestra muestra incluía más hombres que mujeres (67 vs. 33%). Además, la distribución de hombres y mujeres no era equitativa entre los dos grupos; había un número significativamente mayor de hombres en el grupo de pacientes con síntomas en el lado izquierdo (77 vs. 23%), mientras que la distribución por sexo era similar en el grupo de pacientes con síntomas en el lado derecho (51 vs. 49%). No encontramos diferencias en las puntuaciones de ninguna de las pruebas neuropsicológicas entre los grupos. Sin embargo, las mujeres, independientemente del lado afecto, obtuvieron mejores resultados que los hombres en la prueba de denominación. Conclusiones: Los hombres eran mucho más numerosos en el grupo de pacientes con afectación del lado izquierdo; este grupo mostró peores puntuaciones en la escala de Schwab y England...(AU)

Gender may be related to the side of the motor syndrome and cognition in idiopathic Parkinson's disease.

BACKGROUND: and Sex and cognitive profile may be related to the laterality of motor symptoms in idiopathic Parkinson's disease. INTRODUCTION: Parkinson's disease (PD) is well recognised as an inherently asymmetric disease with unilateral onset of motor symptoms. The laterality of motor symptoms may be linked to sex, clinical and demographic variables, and neuropsychological disorders. However, the available data are inconsistent. This study aimed to explore the potential association between the laterality of motor symptoms and clinical and demographic variables and deficits in specific cognitive domains. MATERIAL AND METHODS: We retrospectively recruited 97 participants with idiopathic PD without dementia; 60 presented motor symptoms on the left side and 37 on the right side. Both groups were comparable in terms of age, age at disease onset, disease duration, and severity of the neurological deficits according to the Unified Parkinson's Disease Rating Scale and the Hoehn and Yahr scale. RESULTS: Participants with left-side motor symptoms scored lower on the Schwab and England Activities of Daily Living scale. Our sample included more men than women (67% vs. 33%). Both sexes were not equally represented in the 2 groups: there were significantly more men than women in the group of patients with left-side motor symptoms (77% vs. 23%), whereas the percentages of men and women in the group of patients with right-side motor symptoms were similar (51% vs. 49%). Both groups performed similarly in all neuropsychological tasks, but women, independently of laterality, performed better than men in the naming task. CONCLUSION: We found a clear prevalence of men in the group of patients with left-side motor symptoms; this group also scored lower on the Schwab and England Scale. Female sex was predictive of better performance in the naming task. Sex should always be considered in disorders that cause asymmetric involvement of the brain, such as PD.

Psychopathological profile in COVID-19 patients including healthcare workers: the implications.

OBJECTIVE: The effects of COVID-19 seem to extend beyond the physical pain and is showing psychiatric implications as well. Moreover, psychopathological implications seem to last also after patients' discharge. Our goal is to investigate the psychological impact and psychopathological outcome of patients affected by COVID-19. PATIENTS AND METHODS: We have engaged 34 patients with COVID-19 conditions [eight of them were healthcare workers patients (HCW)] hospitalized at "Policlinico Gemelli Foundation" of Rome, Italy. All patients were evaluated through the Impact of Event Scale-Revised (IES-R) and the Symptom Checklist 90-R (SCL-90-R) first, during their hospitalization (baseline), and then, after 4 months from hospital discharge (follow-up), through phone interviews. RESULTS: At baseline, 82% of patients revealed from mild to severe psychological impact of COVID-19, according to the IES-R. At follow-up, the mean IES-R total score was significantly decreased (p<0.001) even if almost half (46.6%) of our cohort still showed it. HCW patients showed a significantly higher score than other patients at IES-R scale, both at baseline (p=0.005) and at follow-up (p<0.001). Moreover, at 4 months from discharge, they showed a significantly higher percentage of moderate and severe distress (p=0.015). In addition to this, at follow-up, our cohort of patients showed an increase of anxiety symptoms, even if not significant compared to baseline (46.7% vs. 35.3% respectively; p=1.000), and HCW patients suffered more sleep disorders (p=0.019) and anxiety symptoms (p=0.019) compared to other patients. CONCLUSIONS: We indicate the importance of assessing psychopathology of COVID-19 survivors, monitoring their changes over time, and providing psychological support to improve their psychological well-being.

Comparison of cognitive performance in HIV or HCV mono-infected and HIV-HCV co-infected patients.

PURPOSE: Our aim was to explore the interplay between human immunodeficiency virus (HIV) and hepatitis C virus (HCV) infections in the expression of cognitive disorders. METHODS: We performed a multi-centre cross-sectional study, enrolling three groups of asymptomatic outpatients matched for age and education: (1) HIV mono-infected; (2) HCV mono-infected; (3) HIV-HCV co-infected. All subjects were subjected to the Zung depression scale and a comprehensive neuropsychological battery. RESULTS: A total of 50 patients for each group were enrolled. Patients in the three groups did not significantly differ in the main common demographic and clinical characteristics, except for a lower proportion of past injecting drug use (IDU) in group 1 (4 %) in comparison to groups 2 (38 %, p < 0.001) and 3 (78 %, p < 0.001), a longer duration of HIV infection in group 3 in comparison to group 1 (p < 0.001) and a longer duration of HCV infection in group 3 in comparison to group 2 (p = 0.028). Overall, 39.3 % of patients showed minor cognitive impairment, with a higher proportion in group 3 (54 %) when compared to groups 1 (28 %, p = 0.015) or 2 (36 %, p = 0.108). Patients in group 3 [odds ratio (OR) 3.35, p = 0.038 when compared to group 1] and those with higher depression scores (OR 1.05, p = 0.017) showed an increased risk of cognitive impairment after adjusting for education and past injection drug use. In particular, group 3 showed worse performance in psychomotor speed tasks when compared to group 1 (p = 0.033). CONCLUSIONS: A worse cognitive performance in HIV-HCV co-infected patients was observed, suggesting an additive role of the two viruses in the pathogenesis of cognitive disorders.

Cardiovascular risk factors and carotid intima-media thickness are associated with lower cognitive performance in HIV-infected patients.

OBJECTIVES: The aim of the study was to investigate the relationship between metabolic comorbidities, cardiovascular risk factors or common carotid intima-media thickness (cIMT) and cognitive performance in HIV-infected patients. METHODS: Asymptomatic HIV-infected subjects were consecutively enrolled during routine out-patient visits at two clinical centres. All patients underwent an extensive neuropsychological battery and assessment of metabolic comorbidities and cardiovascular risk factors. Moreover, cIMT was assessed by ultrasonography. Cognitive performance was evaluated by calculating a global cognitive impairment (GCI) score obtained by summing scores assigned to each test (0 if normal and 1 if pathological). RESULTS: A total of 245 patients (median age 46 years; 84.1% with HIV RNA < 50 copies/mL; median CD4 count 527 cells/µL) were enrolled in the study. Cardiovascular risk factors were highly prevalent in our population: the most frequent were dyslipidaemia (61.2%), cigarette smoking (54.3%) and hypertension (15.1%). cIMT was abnormal (≥ 0.9mm) in 31.8% of patients. Overall, the median GCI score was 2 [interquartile range (IQR) 1-4]; it was higher in patients with diabetes (P = 0.004), hypertension (P = 0.030) or cIMT ≥ 0.9 mm (P < 0.001). In multivariate analysis, it was confirmed that diabetes (P = 0.007) and cIMT ≥ 0.9 mm (P = 0.044) had an independent association with lower cognitive performance. In an analysis of patients on combination antiretroviral therapy (cART), abacavir use was independently associated with a better cognitive performance (P = 0.011), while no association was observed for other drugs or neuroeffectiveness score. CONCLUSIONS: Diabetes, cardiovascular risk factors and cIMT showed a strong association with lower cognitive performance, suggesting that metabolic comorbidities could play a relevant role in the pathogenesis of HIV-associated neurocognitive disorders in the recent cART era.

Efavirenz associated with cognitive disorders in otherwise asymptomatic HIV-infected patients.

BACKGROUND: Despite the availability of potent antiretroviral regimens (combination antiretroviral therapy [cART]), HIV-associated neurocognitive disorders (HAND) are increasingly recognized. Our aim was to investigate the prevalence and treatment-related correlates of HAND, exploring the potential neurotoxicity of antiretrovirals on cognitive functions. METHODS: We performed a cross-sectional single cohort study by consecutively enrolling asymptomatic HIV+ subjects during routine outpatient visits. Each patient was submitted to a comprehensive neuropsychological battery and was considered cognitively impaired on the basis of results obtained in matched healthy HIV-negative subjects. CNS penetration effectiveness (CPE) rank was calculated for cART regimens according to 2010 CHARTER criteria. Factors associated with cognitive impairment were investigated by linear or logistic regression analysis. RESULTS: A total of 146 patients were enrolled. Of these, 129 (88.4%) were on cART and 59.6% of them were on current regimen from ≥1 year. Sixty-nine patients (47%) were classified as cognitively impaired (35.6% asymptomatic and 11.6% mild neurocognitive impairment). In the multivariate analysis, efavirenz use (odds ratio [OR] = 4.00; p = 0.008) and non-Italian nationality (OR = 3.46; p = 0.035) were associated with increased risk of cognitive impairment, whereas higher education was associated with a lower risk (OR = 0.85; p = 0.002). Furthermore, efavirenz use and age ≥65 years independently predicted worse performance on the double barrage and the Stroop test (time). No association between CPE rank and cognitive impairment was observed. CONCLUSIONS: A high prevalence of HAND was observed in apparently asymptomatic HIV+ individuals. HAND was associated with efavirenz use, suggesting the potential neurotoxicity of this drug. Routine neuropsychological examinations could help clinicians make correct diagnoses and manage mild, but clinically relevant, forms of HAND.

BuChE K variant is decreased in Alzheimer's disease not in fronto-temporal dementia.

Alzheimer's disease (AD) is characterized by a significant reduction in AcetylCholinesterase and an increase in ButyrylCholinesterase (BuChE) activity. The existence of polymorphic regions on the BuChE gene has been previously described; the most frequently found polymorphism is the so-called K variant, which leads to a 30% decreased enzymatic activity. Different studies reported a positive association between K variant and AD, strongest among late-onset AD and Apolipoprotein E (APOE) e4 carriers. We analyzed APOE and BuChE polymorphisms in 167 AD and 59 fronto-temporal dementia (FTD) patients compared with 129 healthy controls (HC). We reported a significantly lower frequency of the BuChE K variant in AD compared with HC and FTD and a significant increased frequency of the K variant in FTD. These results are in agreement with the known increase of the BuChE activity in AD and support the evidence of different molecular pathways involved in the pathogenesis of AD and FTD.

Can cognitive and behavioural disorders differentiate frontal variant-frontotemporal dementia from Alzheimer's disease at early stages?

Frontal variant-Frontotemporal dementia (fvFTD) and Alzheimer's disease (AD) patients matched for severity of dementia at the Clinical Dementia Rating (CDR) received neuropsychological testing in order to explore if the dysexecutive disorder might characterise fvFTD at early stage, when AD is dominated by the episodic memory defect. We also determined if the behavioural syndrome was more severe in fvFTD than AD, and if specific patterns of behavioural symptoms could differentiate the two types of dementia, using the Neuropsychiatry Inventory (NPI). AD patients performed worse than fvFTD not only in memory but also in executive tasks. Apathy and eating disorders proved to be more severe or frequent in fvFTD even if the two groups did not differ in the total NPI score. CDR score significantly correlated with the NPI score in fvFTD and with the MMSE in AD. Our data confirm that the memory disorders may differentiate the two types of dementia; however, the dysexecutive syndrome is as severe, and even more severe in AD. The severity of the behavioural syndrome is comparable in the two groups but the nature of the behavioural disorders may vary to some extent. We conclude that AD dementia at early stage is a behavioural-cognitive syndrome, while in fvFTD the behavioural disorders appear when the cognitive deficit is still relatively mild.

Behavior in degenerative dementias: mood disorders, psychotic symptoms and predictive value of neuropsychological deficits.

We studied mood disorders (MD) and psychotic symptoms (PS) in patients with fronto -temporal dementia (FTD) and Alzheimer's disease (AD) by means of different diagnostic instruments. These were: a subjective scale (subsets of survey psychiatric assessment schedule: SPAS), an objective scale (subsets of neuropsychiatric inventory: NPI) and a projective task (Wartegg completion task: WCT). A general tendency of NPI to over estimate the presence of symptoms compared to SPAS was observed, but distribution and severity of symptoms were quite homogeneous in the two dementia-groups, independently of the diagnostic scales. At variance with the scales, the WCT showed a more severe impairment in FTD than in AD. The regression analysis selected neuropsychological models able to predict behavioral disorders only in FTD, in particular, a planning deficit predicted PS. These data confirm the hypothesis that a damage in the frontal areas constitutes the neurobiological basis of PS in degenerative brain diseases. Furthermore, they suggest that mostly in FTD, behavioral disorders, as well as cognitive deficits, should be considered a direct expression of neural damage.

Impairment of verb processing in frontal variant-frontotemporal dementia: a dysexecutive symptom.

Object and action naming and comprehension were tested in frontotemporal dementia (frontal variant, FTD), in Alzheimer's disease (AD) and in controls. Although lower scores were obtained by all groups, we can confirm that actions were proportionally more impaired in FTD. The correlation between action naming deficit and severity of dementia was stronger in this group than in AD. The correlation analysis also suggested that the naming disorder was different in nature in FTD (mostly a dysexecutive deficit) and in AD (mostly a linguistic disorder). Our explanation is that since verbs are supposed to be more demanding of executive resources than nouns, a higher sensitivity to verbs should be expected in any brain pathology, but mostly in FTD in which executive resources are typically reduced.

Right side neglect in right cerebellar lesion.

A patient is described who developed right side hemineglect after a right cerebellar lesion. This spatial disorder was interpreted as a secondary effect of a deficit of the motor organisation in the right hemispace due to left frontal diaschisis. The pathological base may be the interruption of a highly integrated system which includes the lateral cerebellum and the contralateral frontal lobe.

Olivopontocerebellar atrophy: paraneoplastic syndrome of brain tumour?

We describe a patient who, three years after the onset of an olivopontocerebellar atrophy, developed a right cerebral tumour. The cerebellar symptomatology also included, as in other cerebellar patients previously described, a peripheral dysgraphia. Because this deficit of writing is generally reported in patients with right cerebral lesion, the authors hypothesized that functional alterations of supratentorial structures preceding the tumour by years may be able to damage the neural substrates connecting cerebral and cerebellar structures and to produce cerebellar atrophy.

Predictors of cognitive decline in the early stage of probable Alzheimer's disease.

Several papers have attempted to find neurological and neuropsychological predictors of progression in Alzheimer's disease (AD) till now. Despite this quite large amount of works, different and not univocal conclusions have been reported in this field. Different study samples, different end-points and differences in statistical methods can explain much of the inconsistency in the results obtained. In our study, AD patients were examined in a very early stage of the disease to avoid any possible risk to examine subjects at different times of evolution. All the patients underwent an extensive neuropsychological test battery twice (baseline and follow-up) spaced out over about 1 year and were divided into two groups of fast decliners (FD) and slow decliners (SD) on the basis of their rate of decay at the MMSE score. Verbal memory tests, mental control abilities and attention-demanding tasks seem to play a pivotal role in distinguishing the two groups of subjects in the early stage of the disease. Moreover, FD patients show a worse performance than SD at the baseline in most of the cognitive domains explored. In conclusion, different subtypes of AD do exist and an important predictor of progression is represented by the severity of the cognitive impairment at the onset.

Phonological grouping is specifically affected in cerebellar patients: a verbal fluency study.

OBJECTIVES: Recent clinical and functional neuroimaging evidence points towards a cerebellar role in verbal production. At present it is not clear how the cerebellum participates in language production. The aim was to investigate the influence of cerebellar lesions on verbal fluency abilities with specific focus on the verbal searching strategies employed by patients with cerebellar damage. METHODS: Twenty five patients with focal or degenerative cerebellar disease and 14 control subjects were tested in a timed verbal fluency task requiring word production under forced (phonemic or semantic) conditions. To analyse the verbal searching strategy employed, semantic and phonemic cluster analyses were also performed. RESULTS: Performances of cerebellar patients were comparable with those of controls in the semantic task; conversely their performances were significantly impaired when tested in the letter task. Cluster analysis results showed that the verbal fluency impairment is linked to specific damage of phonemically related retrieval strategies. CONCLUSION: Cerebellar damage impairs verbal fluency by specifically affecting phonemic rule performances while sparing semantic rule ones. These findings underline the importance of the cerebellar computing properties in strategy development in the linguistic domain.

Anatomical and psychological mechanism of reduplicative misidentification syndromes.

Reduplicative misidentifications syndromes (RMS) are rare memory disorders characterized by the subjective conviction that a place, person or event is duplicated. Even if RMS often follow a right frontal lesion, several studies have stressed the importance of bilateral hemispheric pathology. Moreover, from a psychological perspective, there is uncertainty if this symptom should be considered just as a kind of confabulation or if it should be associated with personal psychosocial and behavioral aspects. We report a patient who developed normal pressure hydrocephalus and RMS one year after a post-traumatic right frontal lesion. At the first neuropsychological evaluation, we found mild impairment of all functions, associated with the presence of reduplicative paramnesia. After the ventricle-peritoneal shunt intervention, we observed a progressive improvement of all functions but the frontal ones. The memory deficit became less specific and the RMS disappeared. We therefore postulate that a focal right frontal lesion is not sufficient to cause RMS per se. Our clinical report suggests that paramnesic events held on reasonable ground, not being just a kind of confabulation.

Linguistic and non-linguistic abilities in a patient with early left hemispherectomy.

A patient who underwent early removal of the left hemisphere because of Sturge-Weber syndrome was submitted to detailed linguistic and visuospatial batteries. The performances were compared to performances of subjects matched for age, education and IQ, but without focal cerebral lesions. Language was mildly impaired but to the same extent as in IQ controls. On the contrary, visuospatial abilities were clearly worse than in IQ controls, and the most preserved visuospatial abilities seemed to be the less sophisticated ones. Non literal comprehension of language, a function generally attributed to the right hemisphere, was intact. This same pattern, that is, preservation of language and impairment of visuospatial abilities, also seems to occur in subjects who have undergone surgical removal of the right hemisphere; in other words, the cognitive pattern seems the same regardless of which hemisphere is removed. These observations suggest that no matter which hemisphere is removed, functional reorganisation follows a hierarchical criterion which privileges the linguistic function, and the visuospatial functions most essential for independent survival.

Verbal short-term store-rehearsal system and the cerebellum. Evidence from a patient with a right cerebellar lesion.

We describe an 18-year-old patient who underwent surgical removal of the right cerebellar hemisphere for the presence of a neoplastic lesion. After surgery, the patient's neuropsychological examination was normal except for a transient selective verbal short-term memory (STM) impairment characterized by reduced verbal digit span and rapid forgetting of verbal material. An extensive examination of the patient's deficit was performed in order to identify which of the two components of STM (phonological short-term store and/or rehearsal system) was impaired. The functional locus of the deficit was identified at the level of the phonological output buffer, a component of the rehearsal system, as suggested by the pattern of results obtained, namely: the improvement of the digit span seen with pointing compared with the verbal response; the advantage of auditory over visual presentation of digits; and the lack of a phonological-similarity effect with visual presentation of letters. On the other hand, the functioning of the phonological store was demonstrated by the normal amplitude of the recency effect in free recall of words and by the phonological-similarity effect with auditory presentation of letters. Our finding is consistent with previous functional (PET) studies showing the involvement of the right cerebellum during tasks requiring silent recirculation of verbal information. We conclude that the cerebellum takes part in the planning of speech production at a level that does not require an overt articulation.

Cerebellum and procedural learning: evidence from focal cerebellar lesions.

The aim of the present study was to investigate the influence of focal cerebellar lesions on procedural learning. Eight patients with cerebellar lesions and six control subjects were tested in a serial reaction-time task. A four-choice reaction-time task was employed in which the stimuli followed (or not) a sequence repeated 10 times, with the subjects aware (or not) of the item sequence. Learning was manifested by the reduction in response latency over the sequential blocks. Acquisition of declarative knowledge of the sequence was also tested. Reaction times displayed by patients with cerebellar lesions, even though they tended to be longer than those of control subjects in all testing conditions, significantly differed from control subjects only when the stimuli were presented in sequence. The reaction times in sequential trials were still statistically significant when simple motor response times were taken into account. Cerebellar patients were also significantly impaired in detecting and repeating the sequence. On the other hand, when the sequence was learned before testing, motor performances were significantly improved in all subjects. These data indicate that cerebellar lesions induce specific impairment in the procedural learning of a motor sequence and suggest a role of the cerebellar circuitry in detecting and recognizing event sequences.