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Stroke Jan 2024Stroke survivors with impaired balance and motor function tend to have relatively poor functional outcomes. The cerebellum and primary motor cortex (M1) have been... (Randomized Controlled Trial)
Randomized Controlled Trial
BACKGROUND
Stroke survivors with impaired balance and motor function tend to have relatively poor functional outcomes. The cerebellum and primary motor cortex (M1) have been suggested as targets for neuromodulation of balance and motor recovery after stroke. This study aimed to compare the efficacy and safety of intermittent theta-burst stimulation (iTBS) to the cerebellum or M1 on balance and motor recovery in patients with stroke.
METHODS
In this randomized, double-blind, sham-controlled clinical trial, patients with subacute stroke were randomly divided into 3 groups: M1-, cerebellar-, and sham-iTBS (n=12 per group; 15 sessions, 3 weeks). All outcomes were evaluated before intervention (T0), after 1 week of intervention (T1), after 3 weeks of intervention (T2), and at follow-up (T3). The primary outcome was the Berg balance scale score at T2. Secondary outcomes include the Fugl-Meyer assessment scale for lower extremities, the trunk impairment scale, the Barthel index, the modified Rankin Scale, the functional ambulation categories, and cortical excitability.
RESULTS
A total of 167 inpatients were screened, 36 patients (age, 57.50±2.41 years; 10 women, 12 ischemic) were enrolled between December 2020 and January 2023. At T2, M1- or cerebellar-iTBS significantly improved Berg balance scale scores by 10.7 points ([95% CI, 2.7-18.6], =0.009) and 14.2 points ([95% CI, 1.2-27.2], =0.032) compared with the sham-iTBS group. Moreover, the cerebellar-iTBS group showed a significantly greater improvement in Fugl-Meyer assessment scale for lower extremities scores by 5.6 points than the M1-iTBS ([95% CI, 0.3-10.9], =0.037) and by 7.8 points than the sham-iTBS ([95% CI, 1.1-14.5], =0.021) groups at T2. The motor-evoked potential amplitudes of the M1- and cerebellar-iTBS groups were higher than those of the sham-iTBS group (<0.001).
CONCLUSIONS
Both M1- and cerebellar-iTBS could improve balance function. Moreover, cerebellar-iTBS, but not M1-iTBS, induced significant effects on motor recovery. Thus, cerebellar-iTBS may be a valuable new therapeutic option in stroke rehabilitation programs.
REGISTRATION
URL: https://www.chictr.org.cn/; Unique identifier: ChiCTR2100047002.
Topics: Humans; Female; Middle Aged; Transcranial Magnetic Stimulation; Motor Cortex; Stroke; Stroke Rehabilitation; Cerebellum
PubMed: 38037225
DOI: 10.1161/STROKEAHA.123.044892 -
Acta Neurologica Belgica Oct 2023
Topics: Infant, Newborn; Humans; Cerebellum; Hydrocephalus; Cerebellar Diseases; Infant, Newborn, Diseases; Rhombencephalon; Magnetic Resonance Imaging
PubMed: 36064837
DOI: 10.1007/s13760-022-02080-2 -
Cerebellum (London, England) Oct 2023The effectiveness of cerebellar repetitive transcranial magnetic stimulation (rTMS) on motor dysfunction in patients with neurological disorders has received increasing... (Review)
Review
The effectiveness of cerebellar repetitive transcranial magnetic stimulation (rTMS) on motor dysfunction in patients with neurological disorders has received increasing attention because of its potential for neuromodulation. However, studies on the neuromodulatory effects, parameters, and safety of rTMS implementation in the cerebellum to alleviate motor dysfunction are limited. This systematic review aimed to evaluate the effectiveness and safety of cerebellar rTMS treatment for motor dysfunction caused by neurological disorders and to review popular stimulation parameters. Five electronic databases-Medline, Web of Science, Scopus, Cochrane Library, and Embase-were searched for relevant research published from inception to July 2022. All randomized controlled trials (RCTs) that reported the effects of cerebellar rTMS combined with behavioral rating scales on motor dysfunction were eligible for enrollment. Additionally, reference lists of the enrolled studies were manually checked. Among 1156 articles screened, 21 RCTs with 666 subjects were included. rTMS conducted on the cerebellum showed an improvement in stroke (spasticity, balance, and gait), cervical dystonia, Parkinson's disease (tremor), cerebellar ataxia, and essential tremor but not in multiple sclerosis. The 8-shaped coil with a diameter of 70 mm was determined as the most common therapeutic choice. None of the studies reported severe adverse events except mild side effects in three. Therefore, rTMS appears to be a promising and safe technique for the treatment of motor dysfunction, targeting the cerebellum to induce motor behavioral improvement. Further rigorous RCTs, including more samples and longer follow-up periods, are required to precisely explore the effective stimulation parameters and possible mechanisms.
Topics: Humans; Transcranial Magnetic Stimulation; Cerebellum; Essential Tremor; Parkinson Disease; Stroke
PubMed: 36018543
DOI: 10.1007/s12311-022-01465-6 -
Acta Neurochirurgica May 2024The dentate nucleus (DN) is the largest, most lateral, and phylogenetically most recent of the deep cerebellar nuclei. Its pivotal role encompasses the planning,... (Review)
Review
PURPOSE
The dentate nucleus (DN) is the largest, most lateral, and phylogenetically most recent of the deep cerebellar nuclei. Its pivotal role encompasses the planning, initiation, and modification of voluntary movement but also spans non-motor functions like executive functioning, visuospatial processing, and linguistic abilities. This review aims to offer a comprehensive description of the DN, detailing its embryology, anatomy, physiology, and clinical relevance, alongside an analysis of dentatotomy.
METHODS AND RESULTS
We delve into the history, embryology, anatomy, vascular supply, imaging characteristics, and clinical significance of the DN. Furthermore, we thoroughly review the dentatotomy, emphasizing its role in treating spasticity.
CONCLUSIONS
Understanding the intricacies of the anatomy, physiology, vasculature, and projections of the DN has taken on increased importance in current neurosurgical practice. Advances in technology have unveiled previously unknown functions of the deep cerebellar nuclei, predominantly related to non-motor domains. Such discoveries are revitalizing older techniques, like dentatotomy, and applying them to newer, more localized targets.
Topics: Humans; Cerebellar Nuclei; Neurosurgical Procedures; Muscle Spasticity
PubMed: 38758379
DOI: 10.1007/s00701-024-06104-z -
ELife Dec 2023Several discrete groups of feeding-regulated neurons in the nucleus of the solitary tract (; NTS) suppress food intake, including avoidance-promoting neurons that...
Several discrete groups of feeding-regulated neurons in the nucleus of the solitary tract (; NTS) suppress food intake, including avoidance-promoting neurons that express (NTS cells) and distinct - and -expressing neurons (NTS and NTS cells, respectively) that suppress food intake without promoting avoidance. To test potential synergies among these cell groups, we manipulated multiple NTS cell populations simultaneously. We found that activating multiple sets of NTS neurons (e.g. NTS plus NTS [NTS], or NTS plus NTS [NTS]) suppressed feeding more robustly than activating single populations. While activating groups of cells that include NTS neurons promoted conditioned taste avoidance (CTA), NTS activation produced no CTA despite abrogating feeding. Thus, the ability to promote CTA formation represents a dominant effect but activating multiple non-aversive populations augments the suppression of food intake without provoking avoidance. Furthermore, silencing multiple NTS neuron groups augmented food intake and body weight to a greater extent than silencing single populations, consistent with the notion that each of these NTS neuron populations plays crucial and cumulative roles in the control of energy balance. We found that silencing NTS neurons failed to blunt the weight-loss response to vertical sleeve gastrectomy (VSG) and that feeding activated many non-NTS neurons, however, suggesting that as-yet undefined NTS cell types must make additional contributions to the restraint of feeding.
Topics: Solitary Nucleus; Neurons; Eating
PubMed: 38059498
DOI: 10.7554/eLife.85640 -
Cerebellum (London, England) Dec 2023The longstanding idea that the cerebral cortex is the main neural correlate of human cognition can be elaborated by comparative analyses along the vertebrate... (Review)
Review
The longstanding idea that the cerebral cortex is the main neural correlate of human cognition can be elaborated by comparative analyses along the vertebrate phylogenetic tree that support the view that the cerebello-cerebral system is suited to support non-motor functions more generally. In humans, diverse accounts have illustrated cerebellar involvement in cognitive functions. Although the neocortex, and its transmodal association cortices such as the prefrontal cortex, have become disproportionately large over primate evolution specifically, human neocortical volume does not appear to be exceptional relative to the variability within primates. Rather, several lines of evidence indicate that the exceptional volumetric increase of the lateral cerebellum in conjunction with its connectivity with the cerebral cortical system may be linked to non-motor functions and mental operation in primates. This idea is supported by diverging cerebello-cerebral adaptations that potentially coevolve with cognitive abilities across other vertebrates such as dolphins, parrots, and elephants. Modular adaptations upon the vertebrate cerebello-cerebral system may thus help better understand the neuroevolutionary trajectory of the primate brain and its relation to cognition in humans. Lateral cerebellar lobules crura I-II and their reciprocal connections to the cerebral cortical association areas appear to have substantially expanded in great apes, and humans. This, along with the notable increase in the ventral portions of the dentate nucleus and a shift to increased relative prefrontal-cerebellar connectivity, suggests that modular cerebellar adaptations support cognitive functions in humans. In sum, we show how comparative neuroscience provides new avenues to broaden our understanding of cerebellar and cerebello-cerebral functions in the context of cognition.
Topics: Animals; Humans; Phylogeny; Cerebellum; Cerebral Cortex; Primates; Cognition; Magnetic Resonance Imaging; Neural Pathways
PubMed: 36417091
DOI: 10.1007/s12311-022-01495-0 -
Neurosurgical Review Jul 2023The dentato-rubro-olivary pathway, also known as the Guillain-Mollaret triangle (GMT) or myoclonic triangle, consists of the dentate nucleus, the red nucleus, and the... (Review)
Review
The dentato-rubro-olivary pathway, also known as the Guillain-Mollaret triangle (GMT) or myoclonic triangle, consists of the dentate nucleus, the red nucleus, and the inferior olivary nucleus (ION). GMT is important for motor coordination and control, and abnormalities in this network can lead to various neurological disorders. The present study followed a systematic approach in conducting a review on GMT studies. The inclusion criteria were limited to human subjects with primary objectives of characterizing and evaluating GMT syndromes, and the methodology used was not a determining factor for eligibility. The search strategy used MeSH terms and keywords relevant to the study's objective in various databases until August 2022. A total of 76 studies were included in the review after assessing 527 articles for eligibility based on the final inclusion criteria. Most of the studies evaluated the GMT in human subjects, with the majority utilizing magnetic resonance imaging (MRI), diffusion tensor imaging (DTI), or combination of them. The review found that Hypertrophic olivary degeneration (HOD), a common consequence of GMT damage, has diverse underlying causes, including stroke, brainstem cavernous malformations, and structural impairments. Palatal tremor, ocular myoclonus, ataxia, nystagmus, and vertigo were frequently reported symptoms associated with HOD. This systematic review provides comprehensive insights into the association between GMT and various neurological syndromes, shedding light on the diagnostic, etiological, and prognostic aspects of GMT dysfunction. Understanding the role of the GMT and its implications in movement disorders could pave the way for improved treatment options and better management of neurological conditions related to this critical brainstem pathway.
Topics: Humans; Diffusion Tensor Imaging; Syndrome; Olivary Nucleus; Magnetic Resonance Imaging; Stroke; Hypertrophy
PubMed: 37468768
DOI: 10.1007/s10143-023-02086-1 -
BMJ Case Reports Dec 2023Chiari malformation (CM) is a group of complex deformities of the posterior fossa and hindbrain, of which CMIII is the rarest. We report a term neonate, with an...
Chiari malformation (CM) is a group of complex deformities of the posterior fossa and hindbrain, of which CMIII is the rarest. We report a term neonate, with an antenatal diagnosis of occipital encephalocele, who underwent resection of the encephalocele and ligation of vessels, with repair of a large scalp defect and dural reconstruction on day 4 of life. The parents of the child had been counselled for a guarded and poor prognosis on initial diagnosis. The child has had a good postoperative course without complications but suffers from cortical visual impairment and global developmental delay.
Topics: Humans; Infant, Newborn; Arnold-Chiari Malformation; Cerebellum; Encephalocele; Magnetic Resonance Imaging; Rhombencephalon
PubMed: 38087482
DOI: 10.1136/bcr-2023-255677 -
Science Advances Jan 2024Transcription factors play vital roles in neuron development; however, little is known about the role of these proteins in maintaining neuronal homeostasis. Here, we...
Transcription factors play vital roles in neuron development; however, little is known about the role of these proteins in maintaining neuronal homeostasis. Here, we show that the transcription factor RREB1 (Ras-responsive element-binding protein 1) is essential for neuron survival in the mammalian brain. A spontaneous mouse mutation causing loss of a nervous system-enriched transcript is associated with progressive loss of cerebellar Purkinje cells and ataxia. Analysis of chromatin immunoprecipitation and sequencing, along with RNA sequencing data revealed dysregulation of RREB1 targets associated with the microtubule cytoskeleton. In agreement with the known role of microtubules in dendritic development, dendritic complexity was disrupted in -deficient neurons. Analysis of sequencing data also suggested that RREB1 plays a role in the endomembrane system. Mutant Purkinje cells had fewer numbers of autophagosomes and lysosomes and contained P62- and ubiquitin-positive inclusions. Together, these studies demonstrate that RREB1 functions to maintain the microtubule network and proteostasis in mammalian neurons.
Topics: Animals; Mice; Mammals; Microtubules; Neurons; Proteostasis; Purkinje Cells; Transcription Factors
PubMed: 38198538
DOI: 10.1126/sciadv.adh3929 -
Arquivos de Neuro-psiquiatria Oct 2023Frontal ataxia, originally described by Bruns, is characterized by the presence of signs of frontal lobe dysfunction, such as perseveration, paratonia, frontal release...
Frontal ataxia, originally described by Bruns, is characterized by the presence of signs of frontal lobe dysfunction, such as perseveration, paratonia, frontal release signs, cognitive changes, and urinary difficulty, associated with imbalance, slow gait, broad-based, the presence of postural instability and falls, retropulsion, and bradykinesia in the lower limbs. The goal of the present study is to recall the historical aspects of this condition, to draw attention to the importance of this clinical finding for the differential diagnosis of ataxias and to review the main semiological differences between primary ataxias (frontal, cerebellar, and sensory ataxia).
Topics: Humans; Ataxia; Cerebellum; Diagnosis, Differential; Frontal Lobe; Gait
PubMed: 37899045
DOI: 10.1055/s-0043-1775886