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Optogenetic activation of the reticular nucleus of the thalamus attenuates limbic seizures via inhibition of the midline thalamus.

OBJECTIVE: The nucleus reticularis of the thalamus (nRT) is most studied in epilepsy for its role in the genesis of absence seizures; much less is known regarding its role in other seizure types, including those originating in limbic structures and the temporal lobe. As it is a major source of inhibitory input to higher order thalamic nuclei, stimulation of the nRT may be an effective strategy to disrupt seizure activity that requires thalamic engagement. METHODS: We recorded single unit activity from the nRT prior to and after infusion of bicuculline into the area tempestas. We monitored sin…

[Functional analysis of the thalamocortical pathways in eye movements].

Although the roles of the thalamocortical pathways in somatic movements are well documented, their roles in eye movements have only recently been examined. The oculomotor-related areas in the frontal cortex receive inputs from the basal ganglia and the cerebellum via the thalamus. Consistent with this, neurons in the paralaminar part of the ventrolateral (VL), ventroanterior (VA), and mediodorsal (MD) nuclei and those in the intralaminar nuclei exhibit a variety of eye movement-related responses. To date, the thalamocortical pathways are known to play at least 2 roles in eye movements. First,

Connections between area 3b of the somatosensory cortex and subdivisions of the ventroposterior nuclear complex and the anterior pulvinar nucleus in squirrel monkeys.

The goal of this study was to determine whether somatosensory thalamic nuclei other than the ventroposterior nucleus proper (VP) have connections with area 3b of the postcentral cortex in squirrel monkeys. Small injections of the anatomical tracers wheat germ agglutinin conjugated to horseradish peroxidase (WGA-HRP) or 3H-proline were placed in electrophysiologically identified representations of body parts. The results indicate that, besides the well-established somatotopically organized connections with VP, area 3b has connections with three other nuclei of the somatosensory thalamus: the ve…

Optimization of white-matter-nulled magnetization prepared rapid gradient echo (MP-RAGE) imaging.

PURPOSE: To optimize the white-matter-nulled (WMn) Magnetization Prepared Rapid Gradient Echo (MP-RAGE) sequence at 7 Tesla (T), with comparisons to 3T. METHODS: Optimal parameters for maximizing signal-to-noise ratio (SNR) efficiency were derived. The effect of flip angle and repetition time (TR) on image blurring was modeled using simulations and validated in vivo. A novel two-dimensional (2D) -centric radial fan beam (RFB) k-space segmentation scheme was used to shorten scan times and improve parallel imaging. Healthy subjects as well as patients with multiple sclerosis and tremor were sca

Responses of thalamic neurons to itch- and pain-producing stimuli in rats.

Understanding of processing and transmission of information related to itch and pain in the thalamus is incomplete. In fact, no single unit studies of pruriceptive transmission in the thalamus have yet appeared. In urethane-anesthetized rats, we examined responses of 66 thalamic neurons to itch- and pain- inducing stimuli including chloroquine, serotonin, β-alanine, histamine, and capsaicin. Eighty percent of all cells were activated by intradermal injections of one or more pruritogens. Forty percent of tested neurons responded to injection of three, four, or even five agents. Almost half of t

Thalamic cramplike pain.

IMPORTANCE: We describe a case of cramplike pain after a left thalamic ischemic stroke, a neglected type of central post-stroke pain and we describe its neuroanatomical correlates. OBSERVATIONS: A 68-year-old right-handed man presented with right arm, leg, and flank cramplike pain noted upon awakening. Neurological examination was normal, with no evidence of objective sensory abnormalities. Because of the nature of the pain and the preserved sensory function, we first did not consider stroke as a potential cause, and suspected that pain was related to the combined effect of intense physical e

Descending projections to the hindbrain and spinal cord in the paddlefish Polyodon spathula.

In vertebrates, almost all motor neurons innervating skeletal muscles are located in the hindbrain and spinal cord, and all brain centers that control behavior have descending projections into these parts of the central nervous system. With tracer injections into the spinal cord and hindbrain, we have studied cell groups with descending projections in the paddlefish. Spinal cord injections reveal retrogradely labeled cells in all reticular and raphe nuclei, as well as the nucleus of the medial longitudinal fascicle. Additional cell groups with projections to the spinal cord are the nucleus of

[The spectrum of prion pathology broadens: fatal familial insomnia].

INTRODUCTION: The small group of prion diseases, caused by accumulation in the brain of an abnormal protein characterized by its aggregation … involving neurone loss and reactive gliosis, particularly affect the anteroventral and dorsomedial thalamic nuclei. These lesions lead to insomnia and to autonomic and endocrine disorders. To a lesser extent and degree, lesions are seen in other thalamic nuclei, the cerebral cortex, inferior olives and the cerebellum. FFI and some families with CJE have the same …

Arterial spin-labeling MR imaging of cerebral hemorrhages.

INTRODUCTION: The purpose of this study is to identify the characteristics of brain perfusion measured by arterial spin-labeling magnetic resonance imaging (ASL-MRI) in cerebral hemorrhages. METHODS: Brain blood flow values (CBF-ASL values) for cerebral and cerebellar hemispheres and segmented cerebral regions were measured by ASL-MRI in 19 putaminal hemorrhage patients and 20 thalamic hemorrhage patients in acute or subacute stages. We assessed the lateralities of CBF-ASL values and the relationships between CBF-ASL values and other imaging findings and clinical manifestations. RESULTS: Bot

Calcium-independent afterdepolarization regulated by serotonin in anterior thalamus.

Previous studies have identified an afterdepolarization (ADP) in thalamocortical neurons that is mediated by an upregulation of the hyperpolarization-activated current I(h). This ADP has been suggested to play a key role in the generation of spindle oscillations. In the lateral geniculate nucleus, upregulation of I(h) has been shown to be signaled by a rise in intracellular calcium leading to the activation of adenylate cyclase and formation of cAMP. However, it is unclear how generalizable this mechanism is to other thalamic nuclei. We have used whole cell recording to examine the electrophys…

Yunis-Varon syndrome: evidence for a lysosomal storage disease.

We present clinical and neuropathological findings in a female infant with Yunis-Varon syndrome (YVS) comprising absence of thumbs and halluces, aphalangia of fingers and toes, hypoplasia of clavicles, severely undermineralized skeleton (especially skull), microcephaly, and multiple nonskeletal anomalies. The patient also had a Dandy-Walker malformation, hydrocephalus, and hypertension, which were not reported previously in YVS. The infant excreted an abnormal unidentified oligosaccharide. The patient died at day 108 with severe neurological impairment. Autopsy showed prominent intraneuronal i

Thalamic and striato-pallidal volumes in schizophrenia patients and individuals at risk for psychosis: A multi-atlas segmentation study.

Despite previous neuroimaging studies demonstrating morphological abnormalities of the thalamus and other subcortical structures in patients with schizophrenia, the potential role of the thalamus and its subdivisions in the pathophysiology of this illness remains elusive. It is also unclear whether similar changes of these structures occur in individuals at high risk for psychosis. In this study, magnetic resonance imaging was employed with the Multiple Automatically Generated Templates (MAGeT) brain segmentation algorithm to determine volumes of the thalamic subdivisions, the striatum (caudat

Радиомикальный подход к клиническому МРТ проясняет связь между Таламом и Когницией в множестве склерозов.

СПРАВОЧНАЯ ИНФОРМАЦИЯ И ЦЕЛЬ: Радиомика излучает изображения, которые, возможно, не поддаются обнаружению в ходе обычного объемного анализа. Учитывая их роль в множестве склероза (MS), мы применили радиомедики к таламическим ядрам и изучили их связи с когнитивными характеристиками. МЕТОДЫ: В общей сложности 601 человек были включены (342 человека с MS [PwMS] из двух когорт и 259 лиц, осуществляющих контроль за состоянием здоровья. Радиомикальные функции (RF) и тома были получены из всего таламуса, пяти таламических ядер, и мутамен был разделен на трехмерные изображения Т1. Когнитивные характер

Совпадение в аннотации оригинала
BACKGROUND AND PURPOSE: Radiomics extracts imaging features that may not be detectable through conventional volumetric analyses. Given their role in multiple sclerosis (MS), we applied radiomics to thalamic nuclei and examined their associations with cognitive performance. METHODS: A total of 601 individuals were included (342 people with MS [PwMS] from two…

Pattern of distribution of serotonergic fibers to the thalamus of the rat.

It is well established that serotonergic (5-hydroxytryptamine, 5-HT) fibers, mainly originating from the dorsal and median raphe nuclei of t … ibers. This pattern of 5-HT innervation indicates that serotonin/ serotonergic fibers mainly affect thalamic nuclei with connections to 'non-principal' or limbic regions of the cortex (or forebrain). This suggests that serotonergic fibers to the thalamus may exert a significant influence on affective and cognitive functions, possibly complementing the actions of …

Structural MRI alterations in children with form-deprivation amblyopia: a propensity score-matched case-control study.

AIMS: Form-deprivation amblyopia (FDAM) is a severe neurodevelopmental disorder from early visual deprivation. This study uses T1-weighted M … Desikan-Killiany-Tourville, Destrieux, subset Brodmann and Aseg), alongside specialised modules for thalamic nuclei and hippocampal-amygdala subfields. Linear regression models adjusted for age and sex were employed for group comparisons with Bonferroni correction. RESULTS: FDAM exhibited widespread structural alterations: Primary visual deficits included right …

Biochemical and autoradiographic studies of the central noradrenergic system in dystonia musculorum mutant mice.

The autosomal recessive mutation dystonia musculorum (dt(J)/dt(J)) causes degenerative alterations of peripheral and central sensory pathway … rast, densities of NA transporters were decreased in hypothalamic subregions and in two ventrobasal thalamic nuclei. The results are discussed in relation to expression of the dystonin gene in normal brain, cellular defects resulting from the loss of gene transcription in the dt(J)/dt(J) mutation, functional circuits of the central nervous system and some of the …

The effects of FG 7142 upon local cerebral glucose utilization suggest overlap between limbic structures important in anxiety and convulsions.

The effects of the beta-carboline benzodiazepine receptor ligand FG 7142 upon local cerebral glucose utilization have been examined in consc … re confined to limbic structures with pronounced effects occurring in the mammillary body, anterior thalamic nuclei, septal nuclei and the oriens and molecular layers of the hippocampus. Glucose use in other structures associated with auditory and visual processing, such as the medial and lateral geniculate body, and associated cortical areas, was also significan …

Glycine receptor distribution in mouse CNS: autoradiographic localization of [3H]strychnine binding sites.

Biochemical and electrophysiological studies of mammalian CNS indicate that the amino-acid, glycine, is a major inhibitory neurotransmitter … the interpeduncular nucleus and the substantia nigra were also clearly delineated, as were certain thalamic nuclei. The cerebellum, cortex, hippocampus and olfactory bulbs showed only very low levels of grain density. In summary, it appears that high concentrations of glycine receptors in the brain and spinal cord may be preferentially localized to neurons invol …

Role of thalamic ventral posterolateral nucleus histamine H2 and opiate receptors in modulation of formalin-induced muscle pain in rats.

BACKGROUND: Histamine and opiate systems contribute to supraspinal processing of pain. In the present study, we investigated the effects of microinjection of histamine and agonists and antagonists of histamine H2 and opiate receptors into the thalamic ventral posterolateral nucleus on muscle pain in rats. METHODS: The thalamic ventral posterolateral nuclei were bilaterally implanted with two guide cannulas. Muscle pain was induced by intramuscular injection of a diluted formalin solution (2.5%, 50μl) into the belly of gastrocnemius muscle, and pain-related behaviors including paw licking dura

7T MRI quantitative susceptibility mapping for magnetic resonance-guided focused ultrasound thalamotomy: methodology and anatomo-clinical correlations in a retrospective pilot study.

Ventral intermediate nucleus (VIM) thalamotomy is an effective treatment for essential tremor (ET). It can be performed incisionlessly by transcranial magnetic resonance-guided focused ultrasound (MRgFUS), aiming for accurate targeting and thermal dose control. Conventional magnetic resonance imaging (MRI) sequences performed at 1.5T or 3T provide limited case-specific information on the topology of intra-thalamic sub-nuclei. Quantitative susceptibility mapping (QSM) MRI enhances the visualization of subcortical structures by leveraging the magnetic properties of tissues, typically the iron co