Role of the Cerebellum in the Construction of Functional and Geometrical Spaces
AbstractThe perceptual and motor systems appear to have a set of movement primitives that exhibit certain geometric and kinematic invariances. Complex patterns and mental representations can be produced by (re)combining some simple motor elements in various ways using basic operations, transformations, and respecting a set of laws referred to as kinematic laws of motion. For example, point-to-point hand movements are characterized by straight hand paths with single-peaked-bell-shaped velocity profiles, whereas hand speed profiles for curved trajectories are often irregular and more variable, with speed valleys and inflecti...
Source: The Cerebellum - April 16, 2024 Category: Neurology Source Type: research
Evaluation of the Patients with the Diagnosis of Pontocerebellar Hypoplasia: A Multicenter National Study
AbstractPontocerebellar hypoplasia (PCH) is a heterogeneous group of neurodegenerative disorders characterized by hypoplasia and degeneration of the cerebellum and pons. We aimed to identify the clinical, laboratory, and imaging findings of the patients with diagnosed PCH with confirmed genetic analysis. We collected available clinical data, laboratory, and imaging findings in our retrospective multicenter national study of 64 patients with PCH in Turkey. The genetic analysis included the whole-exome sequencing (WES), targeted next-generation sequencing (NGS), or single gene analysis. Sixty-four patients with PCH were 28 f...
Source: The Cerebellum - April 15, 2024 Category: Neurology Source Type: research
Prenatal Diagnosis of Cerebellar Cortical Dysplasia: Case Report
AbstractThis was a study of 12 cerebellar cortical dysplasias (CCDs) fetuses, these cases were characterized by a disorder of cerebellar fissures. Historically, CCD diagnosis was primarily performed using postnatal imaging. Unique to this study was the case series of CCD for prenatal diagnosis using prenatal ultrasound, as well as we found thatAXIN1 andFOXC1 mutations may be related to CCD. (Source: The Cerebellum)
Source: The Cerebellum - April 12, 2024 Category: Neurology Source Type: research
Preterm Birth Alters the Regional Development and Structural Covariance of Cerebellum at Term-Equivalent Age
In this study, using the structural MR images of 52 preterm infants scanned at term-equivalent age and 312 full-term controls from the Developing Human Connectome Project, we compared volumetric growth, local cerebellum shape development and cerebello-cerebral structural covariance between the two groups. We found that although there was no significant difference in the overall volume measurements between preterm and full-term infants, the shape measurements were different. Compared with the control infants, preterm infants had significantly larger thickness in the vermis and lower thickness in the lateral portions of the ...
Source: The Cerebellum - April 6, 2024 Category: Neurology Source Type: research
Consensus Paper: Cerebellum and Ageing
In conclusion, macroscopic and microscopic changes occur in the cerebellum during the lifespan, with changes in structural and functional conn ectivity with both the cerebral cortex and basal ganglia. With the aging of the population and the impact of aging on quality of life, the panel of experts considers that there is a huge need to clarify how the effects of aging on the cerebellar circuitry modify specific motor, cognitive, and affect ive operations both in normal subjects and in brain disorders such as AD or MDD, with the goal of preventing symptoms or improving the motor, cognitive, and affective symptoms. (Source: The Cerebellum)
Source: The Cerebellum - March 20, 2024 Category: Neurology Source Type: research
Genetic Epidemiology and Clinical Characteristics of Patients with Spinocerebellar Ataxias in an Unexplored Brazilian State, Using Strategies for Resource-Limited Settings
This study aimed to develop resource-limited strategies to detect and characterize the frequency and genetic-clinical profile of SCAs in an unexplored population from Alagoas State, a low Human Development Index state in northeastern Brazil. Active search strategies were employed to identify individuals with a diagnosis or clinical suspicion of SCAs, and a protocol for clinical and molecular evaluation was applied in collaboration with a reference center in Neurogenetics. A total of 73 individuals with SCAs were identified, with a minimum estimated prevalence of 2.17 cases per 100,000 inhabitants. SCA3 was the most common ...
Source: The Cerebellum - March 20, 2024 Category: Neurology Source Type: research
Consensus Paper: Latent Autoimmune Cerebellar Ataxia (LACA)
We present a novel concept of latent autoimmune cerebellar ataxia (LACA), analogous to latent autoimmune diabetes in adults (LADA). LADA is a slowly progressive form of autoimmune diabetes where patients are often initially diagnosed with type 2 diabetes. The sole biomarker (serum anti-GAD antibody) is not always present or can fluctuate. However, the disease progresses to pancreatic beta-cell failure and insulin dependency within about 5 years. Due to the unclear autoimmune profile, clinicians often struggle to reach an early diagnosis during the period when insulin production is not severely compromised. LACA is also cha...
Source: The Cerebellum - March 20, 2024 Category: Neurology Source Type: research
Ocular Flutter Evoked by Vestibular Stimulation
(Source: The Cerebellum)
Source: The Cerebellum - March 20, 2024 Category: Neurology Source Type: research
Gap Junctions May Have A Computational Function In The Cerebellum: A Hypothesis
We present a detailed neurophysiological and computationally-rendered model of functionally grouped Golgi cells which can infer the density of parallel fibre signals activity and convert it into proportional modulation of inhibition of granule cells. The conversion is unlearned and not actively computed; rather, output is simply the computational effect of cell morphology and network architecture. Unexpectedly, the conversion becomes more precise at low density, suggesting that self-regulation is attracted to sparse code, because it is stable. A computational function of gap junctions may not be confined to the cerebellum....
Source: The Cerebellum - March 18, 2024 Category: Neurology Source Type: research
Effects of Baclofen on Central Paroxysmal Positional Downbeat Nystagmus
This study aims to elucidate the mechanism of central positional nystagmus (CPN) by determining the effects of baclofen on the intensity of paroxysmal positional downbeat nystagmus due to central lesions. Fifteen patients with paroxysmal downbeat CPN were subjected to manual straight head-hanging before administration of baclofen, while taking baclofen 30 mg per day for at least one week, and two weeks after discontinuation of baclofen. The maximum slow phase velocity (SPV) and time constant (TC) of the induced paroxysmal downbeat CPN were analyzed. The positional vertigo was evaluated using an 11-point numerical rating ...
Source: The Cerebellum - March 18, 2024 Category: Neurology Source Type: research
Gravity-Dependent Modulation of Downbeat Nystagmus and Subjective Visual Vertical in the Roll Plane
In this study, we investigated static and dynamic graviceptive function in the roll-plane in patients with DBN (patients) and healthy-controls (controls) by assessment of the Subjective Visual Vertical (SVV) and the modulation of slow-phase-velocity (SPV) of DBN. SPV of DBN and SVV were tested at different head-on trunk-tilt positions in the roll-plane (0 °,30° clockwise (cw) and 30° counterclockwise (ccw)) in 26 patients suffering from DBN and 13 controls. In patients, SPV of DBN did not show significant modulations at different head-tilt angles in the roll-plane. SVV ratings did not differ significantly between DBN pa...
Source: The Cerebellum - March 18, 2024 Category: Neurology Source Type: research
Quantitative Evaluation of Stance as a Sensitive Biomarker of Postural Ataxia Development in Preclinical SCA1 Mutation Carriers
AbstractThe aim of this study was to determine the time between the first detection of postural control impairments and the evident manifestation of ataxia in preclinical SCA1 individuals. Twenty five preclinical SCA1 mutation carriers: 13 with estimated disease onset ≤ 6 years (SCA1 +) aged 27.8 ± 8.1 years; 12 with expected disease onset > 6 years (SCA1-) aged 26.6 ± 3.1 years and 26 age and sex matched healthy controls (HCs) underwent static posturography during 5 years of observation. The movements of the centre of feet pressure (COP) during quiet standing with eyes open (EO) and closed ...
Source: The Cerebellum - March 16, 2024 Category: Neurology Source Type: research
Neuronal Nitric Oxide Synthase Regulates Cerebellar Parallel Fiber Slow EPSC in Purkinje Neurons by Modulating STIM1-Gated TRPC3-Containing Channels
This study investigated the role of nNOS/NO in regulating EPSCSlow. Electrophysiological analyses showed that EPSCSlow in cerebellar slices of nNOS knockout (nNOS−/−) mice was significantly larger than that in wildtype (WT) mice. Activation of mGluR1 in cultured PNs from nNOS−/− mice evoked larger TRPC3-channel mediated currents and intracellular Ca2+ rise than that in PNs from WT mice. In addition, nNOS inhibitor and NO-donor increased and decreased, respectively, the TRPC3-current and Ca2+ rise in PNs. Moreover, the NO-donor effectively decreased TRPC3 currents in HEK293 cells expressing WT STIM1, but not cells e...
Source: The Cerebellum - March 12, 2024 Category: Neurology Source Type: research
The Effect of Nucleo-Olivary Stimulation on Climbing Fiber EPSPs in Purkinje Cells
AbstractClimbing fibers, connecting the inferior olive and Purkinje cells, form the nervous system's strongest neural connection. These fibers activate after critical events like motor errors or anticipation of rewards, leading to bursts of excitatory postsynaptic potentials (EPSPs) in Purkinje cells. The number of EPSPs is a crucial variable when the brain is learning a new motor skill. Yet, we do not know what determines the number of EPSPs. Here, we measured the effect of nucleo-olivary stimulation on periorbital elicited climbing fiber responses through in-vivo intracellular Purkinje cell recordings in decerebrated fer...
Source: The Cerebellum - March 11, 2024 Category: Neurology Source Type: research
Optimizing Communication in Ataxia: A Multifaceted Approach to Alternative and Augmentative Communication (AAC)
AbstractThe progression of multisystem neurodegenerative diseases such as ataxia significantly impacts speech and communication, necessitating adaptive clinical care strategies. With the deterioration of speech, Alternative and Augmentative Communication (AAC) can play an ever increasing role in daily life for individuals with ataxia. This review describes the spectrum of AAC resources available, ranging from unaided gestures and sign language to high-tech solutions like speech-generating devices (SGDs) and eye-tracking technology. Despite the availability of various AAC tools, their efficacy is often compromised by the ph...
Source: The Cerebellum - March 7, 2024 Category: Neurology Source Type: research
