inferior olivary nucleus

Ataxias are characterized by aberrant movement patterns closely related to cerebellar dysfunction. Purkinje cell axons are the sole outputs from the cerebellar cortex, and dysfunctional activity of Purkinje cells has been associated with ataxic movements. However, the synaptic characteristics of Purkinje cells in cases of ataxia are not yet well understood. The nicotinamide antagonist 3-acethylpyridine (3-AP) selectively destroys inferior olivary nucleus neurons so it is widely used to induce cerebellar ataxia...

AIMS: Corticobasal degeneration (CBD) is a rare neurodegenerative disorder. The status of the inferior olivary nucleus (ION) in CBD has been inadequately investigated. In this study, we conducted a pathological investigation of the ION in CBD. MATERIALS AND METHODS: We reviewed the data of Japanese patients with pathologically confirmed CBD who underwent consecutive autopsies between 1985 and 2020 at our institute. We retrospectively examined clinical data from medical records and clinicopathological conferences and semi-quantitatively assessed the ION, central tegmental tract, superior cerebellar peduncle, and dentate nucleus...

Although rats and mice are among the preferred animal models for investigating many characteristics of auditory function, they are rarely used to study an essential aspect of binaural hearing: the ability of animals to localize the sources of low-frequency sounds by detecting the interaural time difference (ITD), that is the difference in the time at which the sound arrives at each ear. In mammals, ITDs are mostly encoded in the medial superior olive (MSO), one of the main nuclei of the superior olivary complex (SOC)...

The posterior intralaminar thalamic nucleus (PIL) and peripeduncular nucleus (PP) are two adjoining structures located medioventral to the medial geniculate nucleus. The PIL-PP region plays important roles in auditory fear conditioning and in social, maternal and sexual behaviors. Previous studies often lumped the PIL and PP into single entity, and therefore it is not known if they have common and/or different brain-wide connections. In this study, we investigate brain-wide efferent and afferent projections of the PIL and PP using reliable anterograde and retrograde tracing methods...

In about 1% of tuberculosis (TB) patients, Mycobacterium tuberculosis (M. tuberculosis) can disseminate to the meninges, causing tuberculous meningitis (TBM) with mortality rate up to 60%. Chronic granulomatous inflammation (non-necrotizing and necrotizing) in the brain is the histological hallmark of TBM. The tryptophan-catabolizing enzyme indoleamine 2,3-dioxygenase 1 (IDO1) and the generated kynurenine metabolites exert major effector functions relevant to TB granuloma functioning. Here we have assessed immunohistochemically IDO1 expression and activity and its effector function and that of its isoform, IDO2, in post-mortem brain tissue of patients that demised with neurotuberculosis...

OBJECTIVE: To assess the utility of diffusion tensor imaging of the auditory pathway in children with sensorineural hearing loss (SNHL). STUDY DESIGN: Retrospective cohort study. SETTING: A single academic tertiary children's hospital. PATIENTS: Sixteen pediatric patients with bilateral SNHL of at least moderate severity in the poorer ear (eight male; mean age, 5.3 ± 4.9 yrs). Controls consisted of age- and sex-matched children with normal hearing who were imaged for nonotologic, non-neurologic medical concerns and found to have normal magnetic resonance imaging (MRI)...

Hypertrophic olivary degeneration (HOD) is a rare form of trans-synaptic degeneration affecting the inferior olivary nucleus (ION). Its classical description involves a lesion in the Guillain-Mollaret triangle (GMT), characteristic imaging findings, and associated oculopalatal tremor. However, understanding of this disease entity is incomplete, as its overall rarity has limited strong classification. Case reports and small studies indicate that a variety of presentations can occur, including non-existent or non-classical lesions as well as variations in physical symptoms...

Multiple system atrophy (MSA) is an adult-onset neurodegenerative disorder that presents with variable combinations of autonomic dysfunction, cerebellar ataxia, parkinsonism, and pyramidal signs. The inferior olivary nucleus is targeted in MSA, with a phenotype of olivopontocerebellar atrophy in particular, and involvement of the olivocerebellar tract is well known. However, degeneration of the olivospinal tract has not been studied in MSA. We examined 97 spinal cords from consecutively autopsied patients with MSA...

UNLABELLED: One of the characteristic areas of brainstem degeneration across multiple spinocerebellar ataxias (SCAs) is the inferior olive (IO), a medullary nucleus that plays a key role in motor learning. In addition to its vulnerability in SCAs, the IO is also susceptible to a distinct pathology known as hypertrophic olivary degeneration (HOD). Clinically, HOD has been exclusively observed after lesions in the brainstem disrupt inhibitory afferents to the IO. Here, for the first time, we describe HOD in another context: spinocerebellar ataxia type 1 (SCA1)...

3-acetylpyridine (3-AP) is a neurotoxin that is known to mainly affect the inferior olivary nucleus (ION) in the brain stem. Although several studies have explored the effect of this neurotoxin, still further investigation is required to understand the impact of this toxin on different parts of the brain. In this research, two groups of rats were studied, the 3-AP-treated and the control groups. Behavioral, stereological, and immunohistochemical analyses were performed. The locomotor activity of the 3-AP-treated rats decreased whereas their anxiety levels were higher than in normal controls...

Monocular torsional eye oscillations are a rare form of disconjugate nystagmus and the underlying pathophysiology is not well understood. Here, we present and discuss a case with disabling torsional oscillopsia in one eye only. The patient exhibited (i) spontaneous pendular torsional nystagmus of the left eye and (ii) rhythmic involuntary movements of the soft palate and uvula, consistent with the syndrome of oculopalatal tremor with monocular nystagmus. Brain MRI revealed an infarct of the left dentate nucleus in the cerebellum and, more caudally, a secondary hypertrophic degeneration of the right inferior olivary nucleus...

A 74-year-old male patient developed multiple infarcts of the brainstem and cerebellum, followed 14 months later by palatal tremor and bilateral vocal cord abduction paralysis, resulting in death due to type 2 respiratory failure. Pathologic analysis revealed old infarcts extending from the bilateral cerebellar cortices to the dentate nucleus, being more extensive on the right side, accompanied by Wallerian degeneration involving the left red nucleus, right central tegmentum tract, and inferior cerebellar peduncle, followed by pseudohypertrophy of the bilateral inferior olivary nuclei...

BACKGROUND: We aimed to investigate the changes that may occur in the auditory neural network in pediatric congenital hearing loss cases. METHODS: Fifty-four cochlear implant candidates and 47 normal-hearing controls were included in this retrospective study. Fractional anisotropy, radial diffusivity, and apparent diffusion coefficient maps were generated. We placed region of interest on the cochlear nucleus, superior olivary nucleus, lateral lemniscus, medial geniculate body, auditory radiation, Heschl's gyrus, inferior fronto-occipital fasciculus, superior longitudinal fascicle, and corpus callosum splenium...

The pathological involvement of the central nervous system in SARS-CoV2 (COVID-19) patients is established. The burden of pathology is most pronounced in the brain stem including the medulla oblongata. Hypoxic/ischemic damage is the most frequent neuropathologic abnormality. Other neuropathologic features include neuronophagia, microglial nodules, and hallmarks of neurodegenerative diseases: astrogliosis and microglial reactivity. It is still unknown if these pathologies are secondary to hypoxia versus a combination of inflammatory response combined with hypoxia...

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 principal neurons (PNs) of the lateral superior olive nucleus (LSO) are an important component of mammalian brainstem circuits that compare activity between the two ears and extract intensity and timing differences used for sound localization. There are two LSO PN transmitter types, glycinergic and glutamatergic, which also have different ascending projection patterns to the inferior colliculus (IC). Glycinergic LSO PNs project ipsilaterally while glutamatergic one's projections vary in laterality by species...

Recent studies have shown that the cerebellum and the basal ganglia are interconnected at subcortical levels. However, a subcortical basal ganglia connection to the inferior olive (IO), being the source of the olivocerebellar climbing fiber system, is not known. We have used classical tracing with CTb, retrograde transneuronal infection with wildtype rabies virus, conditional tracing with genetically modified rabies virus, and examination of material made available by the Allen Brain Institute, to study potential basal ganglia connections to the inferior olive in rats and mice...

Genetic Creutzfeldt-Jakob disease (gCJD) with a V180I mutation (V180I gCJD) is the most common type of gCJD in Japan, characterized by an older age at onset, slower progression, and moderate to severe cortical degeneration with spongiform changes and sparing of the brainstem and cerebellum. Degeneration of the inferior olivary nucleus (IO) is rarely observed in patients with CJD but is known to occur in fatal familial insomnia (FFI) and MM2-thalamic-type sporadic CJD (sCJD-MM2T) involving type 2 prion protein (M2T prion)...

The cerebellum receives inputs via the climbing fibers originating from the inferior olivary nucleus in the ventral medulla. In mammals, the climbing fibers entwine and terminate onto both major and peripheral branches of dendrites of the Purkinje cells. In this study, the inferior olivary nucleus and climbing fiber in the goldfish were investigated with several histological techniques. By neural tracer application to the hemisphere of the cerebellum, labeled inferior olivary neurons were found in the ventral edge of the contralateral medulla...

Objective : Hypertrophic Olivary Degeneration is a rare condition causing transneuronal degeneration of the inferior olivary nucleus. Symptoms manifest as progressively worsening palatal tremor, ataxia, and eye movement disturbances that plateau after several months. Though rarely documented in the literature of this specific condition, disconnection of the inferior olivary nucleus from the cerebellum, and cerebellar atrophy represent a pathway to developing subsequent cerebellar cognitive affective syndrome...