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Neuroradiology Sep 2022This study aimed to compare the alterations of thalamic nuclei volumes and the intrinsic thalamic network in patients with cluster headache and healthy controls.
PURPOSE
This study aimed to compare the alterations of thalamic nuclei volumes and the intrinsic thalamic network in patients with cluster headache and healthy controls.
METHODS
We retrospectively enrolled 24 patients with episodic cluster headache and 24 healthy controls. We calculated the thalamic nuclei volumes in the patients with cluster headache and healthy controls based on three-dimensional T1-weighted imaging with automated segmentation using the FreeSurfer program. We also investigated the intrinsic thalamic network using structural co-variance analysis based on the thalamic nuclei volumes and graph theory under the BRAPH program. We compared the thalamic nuclei volumes and intrinsic thalamic networks in patients with cluster headaches and healthy controls.
RESULTS
The right and left whole thalamic volumes did not differ in the patients with cluster headaches and healthy controls (0.4199 vs. 0.4069%, p = 0.2008; 0.4386 vs. 0.4273%, p = 0.3437; respectively). However, there were significant alterations of right and left medial geniculate nuclei volumes in the patients with cluster headaches and the healthy controls. The right and left medial geniculate nuclei volumes of the patients with cluster headaches were greater than those of the healthy controls (0.0088 vs. 0.0075%, p < 0.0001; 0.0086 vs. 0.0072%, p < 0.0001; respectively). The intrinsic thalamic networks of the groups were not different.
CONCLUSION
This study demonstrates significant alterations in the bilateral medial geniculate nuclei volumes in patients with cluster headache compared to healthy controls. These alterations may be related to the pathophysiology of cluster headache. However, there are no changes in the intrinsic thalamic network in patients with cluster headache.
Topics: Case-Control Studies; Cluster Headache; Humans; Imaging, Three-Dimensional; Magnetic Resonance Imaging; Organ Size; Retrospective Studies; Thalamic Nuclei
PubMed: 35399109
DOI: 10.1007/s00234-022-02951-8 -
Cell Stem Cell May 2023Human brain organoids provide unique platforms for modeling several aspects of human brain development and pathology. However, current brain organoid systems mostly lack...
Human brain organoids provide unique platforms for modeling several aspects of human brain development and pathology. However, current brain organoid systems mostly lack the resolution to recapitulate the development of finer brain structures with subregional identity, including functionally distinct nuclei in the thalamus. Here, we report a method for converting human embryonic stem cells (hESCs) into ventral thalamic organoids (vThOs) with transcriptionally diverse nuclei identities. Notably, single-cell RNA sequencing revealed previously unachieved thalamic patterning with a thalamic reticular nucleus (TRN) signature, a GABAergic nucleus located in the ventral thalamus. Using vThOs, we explored the functions of TRN-specific, disease-associated genes patched domain containing 1 (PTCHD1) and receptor tyrosine-protein kinase (ERBB4) during human thalamic development. Perturbations in PTCHD1 or ERBB4 impaired neuronal functions in vThOs, albeit not affecting the overall thalamic lineage development. Together, vThOs present an experimental model for understanding nuclei-specific development and pathology in the thalamus of the human brain.
Topics: Humans; Thalamic Nuclei; Thalamus; Neurons; Organoids
PubMed: 37019105
DOI: 10.1016/j.stem.2023.03.007 -
World Neurosurgery May 2020The thalamus is a deep cerebral structure that is crucial for proper neurological functioning as it transmits signals from nearly all pathways in the body. Insult to the... (Review)
Review
The thalamus is a deep cerebral structure that is crucial for proper neurological functioning as it transmits signals from nearly all pathways in the body. Insult to the thalamus can, therefore, result in complex syndromes involving sensation, cognition, executive function, fine motor control, emotion, and arousal, to name a few. Specific territories in the thalamus that are supplied by deep cerebral arteries have been shown to correlate with clinical symptoms. The aim of this review is to enhance our understanding of the arterial anatomy of the thalamus and the complications that can arise from lesions to it by considering the functions of known thalamic nuclei supplied by each vascular territory.
Topics: Anterior Thalamic Nuclei; Basilar Artery; Brain Infarction; Circle of Willis; Geniculate Bodies; Humans; Lateral Thalamic Nuclei; Mediodorsal Thalamic Nucleus; Posterior Cerebral Artery; Pulvinar; Thalamus; Ventral Thalamic Nuclei
PubMed: 32036065
DOI: 10.1016/j.wneu.2020.01.237 -
Schizophrenia Research Jun 2023The thalamus is central to brain functions ranging from primary sensory processing to higher-order cognition. Structural deficits in thalamic association nuclei such as...
BACKGROUND
The thalamus is central to brain functions ranging from primary sensory processing to higher-order cognition. Structural deficits in thalamic association nuclei such as the pulvinar and mediodorsal nuclei have previously been reported in schizophrenia. However, the specificity with regards to clinical presentation, and whether or not bipolar disorder (BD) is associated with similar alterations is unclear.
METHODS
We investigated thalamic nuclei volumes in 334 patients with schizophrenia spectrum disorders (SSD) (median age 29 years, 59 % male), 322 patients with BD (30 years, 40 % male), and 826 healthy controls (HC) (34 years, 54 % male). Volumes of 25 thalamic nuclei were extracted from T1-weighted magnetic resonance imaging using an automated Bayesian segmentation method and compared between groups. Furthermore, we explored associations with clinical characteristics across diagnostic groups, including psychotic and mood symptoms and medication use, as well as diagnostic subtype in BD.
RESULTS
Significantly smaller volumes were found in the mediodorsal, pulvinar, and lateral and medial geniculate thalamic nuclei in SSD. Similarly, smaller volumes were found in BD in the same four regions, but mediodorsal nucleus volume alterations were limited to its lateral part and pulvinar alterations to its anterior region. Smaller volumes in BD compared to HC were seen only in BD type I, not BD type II. Across diagnoses, having more negative symptoms was associated with smaller pulvinar volumes.
CONCLUSIONS
Structural alterations were found in both SSD and BD, mainly in the thalamic association nuclei. Structural deficits in the pulvinar may be of relevance for negative symptoms.
Topics: Humans; Male; Adult; Female; Schizophrenia; Bayes Theorem; Thalamic Nuclei; Thalamus; Mediodorsal Thalamic Nucleus; Magnetic Resonance Imaging
PubMed: 37126979
DOI: 10.1016/j.schres.2023.04.008 -
Stereotactic and Functional Neurosurgery 1989Thalamic nuclei implicated in the neural mechanisms of dyskinesia (1) have projections to components of the basal ganglia; (2) receive efferents from the corpus... (Review)
Review
Thalamic nuclei implicated in the neural mechanisms of dyskinesia (1) have projections to components of the basal ganglia; (2) receive efferents from the corpus striatum, and/or (3) project fibers to regions of the cerebral cortex that generate signals which produce or modulate motor phenomenon. The neostriatum receives a major input from the intralaminar thalamic nuclei (ITN). Thalamostriate fibers projecting to the caudate nucleus (CN) and the putamen (Put) originate from different neuronal populations; clusters of cells in the rostral ITN and in the parafascicular nucleus (PF) project to the CN, while cells in the centromedian nucleus (CM) project to the Put. Smaller numbers of cells in the medial, dorsal and ventral nuclear subdivisions of the thalamus also project to the striatum. The amygdaloid nuclear complex receives afferents from the midline thalamic nuclei. Ventromedial and rostral parts of the subthalamic nucleus receive a small input from the centromedian-parafascicular nuclear complex. Segments of the globus pallidus (GP) and the substantia nigra (SN) do not receive afferents from either the cerebral cortex or the thalamus. Thalamic afferents originate ipsilaterally from the medial segment of the globus pallidus (MPS), and the pars reticulata of the substantia nigra (SNR), and contralaterally from the deep cerebellar nuclei (DCN). Each of these projections to nuclear subdivisions of the thalamus is distinctive without overlap. Projections from the MPS are to the ventral anterior pars principalis (VApc) and ventral lateralis, pars oralis (VLo) thalamic nuclei with collaterals to CM. The SNR provides projections to the ventral anterior, pars magnocellularis, the ventral lateral, pars medialis and the mediodorsal, pars paralaminaris thalamic nuclei. Output from the subthalamic nucleus (STN) projects to both the MPS and the SNR and could modulate influences upon thalamic nuclei. In the monkey the projection of STN to the GP is four times greater than to the SNR. The most massive input to the thalamus arises from the contralateral DCN and terminates in the so-called cell-sparse zone, which consists of the ventral posterolateral nucleus, pars oralis, the ventral lateral nucleus pars caudalis, and pars postrema and area x of Olszewski. Nuclear subdivisions of the thalamus receiving afferents from the MPS and the SNR have gamma-aminobutyric acid (GABA) as their major neurotransmitter; fiber systems originating from the DCN appear to have glutamate as their neurotransmitter.(ABSTRACT TRUNCATED AT 400 WORDS)
Topics: Animals; Basal Ganglia; Brain; Humans; Movement Disorders; Neurons; Thalamic Nuclei
PubMed: 2657951
DOI: 10.1159/000099491 -
Trends in Neurosciences Feb 1994The midline and intralaminar thalamic nuclei have long been considered to be a 'nonspecific' nuclear complex that relays the activity of the brain-stem reticular... (Review)
Review
The midline and intralaminar thalamic nuclei have long been considered to be a 'nonspecific' nuclear complex that relays the activity of the brain-stem reticular formation to widespread cerebral-cortical areas. Over the past decade, it has become clear that individual midline and intralaminar nuclei each receive specific sets of afferents and project to specific parts of the cerebral cortex and striatum. Moreover, the targets of the thalamocortical and thalamostriatal projections of a given nucleus are interconnected through corticostriatal projections. Therefore, the midline and intralaminar nuclei might have a dual role in corticosubcortical interactions in the forebrain. Through distinct sets of inputs to individual midline or intralaminar thalamic nuclei, these nuclei are in a position to interact selectively with particular, functionally segregated basal-ganglia-thalamocortical circuits. By way of nonselective inputs, in particular from cholinergic brain-stem nuclei, the midline and intralaminar nuclei might act in concert to modify the level of activity of the entire basal-ganglia-thalamocortical system.
Topics: Animals; Humans; Neural Pathways; Thalamic Nuclei
PubMed: 7512768
DOI: 10.1016/0166-2236(94)90074-4 -
Neurobiology of Learning and Memory Sep 2016The anterior and lateral thalamus has long been considered to play an important role in spatial and mnemonic cognitive functions; however, it remains unclear whether... (Review)
Review
The anterior and lateral thalamus has long been considered to play an important role in spatial and mnemonic cognitive functions; however, it remains unclear whether each region makes a unique contribution to spatial information processing. We begin by reviewing evidence from anatomical studies and electrophysiological recordings which suggest that at least one of the functions of the anterior thalamus is to guide spatial orientation in relation to a global or distal spatial framework, while the lateral thalamus serves to guide behavior in relation to a local or proximal framework. We conclude by reviewing experimental work using targeted manipulations (lesion or neuronal silencing) of thalamic nuclei during spatial behavior and single-unit recordings from neuronal representations of space. Our summary of this literature suggests that although the evidence strongly supports a working model of spatial information processing involving the anterior thalamus, research regarding the role of the lateral thalamus is limited and requires further attention. We therefore identify a number of major gaps in this research and suggest avenues of future study that could potentially solidify our understanding of the relative roles of anterior and lateral thalamic regions in spatial representation and memory.
Topics: Animals; Anterior Thalamic Nuclei; Humans; Lateral Thalamic Nuclei; Spatial Behavior; Spatial Memory
PubMed: 27266961
DOI: 10.1016/j.nlm.2016.06.002 -
NeuroImage Sep 2017The thalamus consists of multiple nuclei that have been previously defined by their chemoarchitectual and cytoarchitectual properties ex vivo. These form discrete,...
The thalamus consists of multiple nuclei that have been previously defined by their chemoarchitectual and cytoarchitectual properties ex vivo. These form discrete, functionally specialized, territories with topographically arranged graduated patterns of connectivity. However, previous in vivo thalamic parcellation with MRI has been hindered by substantial inter-individual variability or discrepancies between MRI derived segmentations and histological sections. Here, we use the Euclidean distance to characterize probabilistic tractography distributions derived from diffusion MRI. We generate 12 feature maps by performing voxel-wise parameterization of the distance histograms (6 feature maps) and the distribution of three-dimensional distance transition gradients generated by applying a Sobel kernel to the distance metrics. We use these 12 feature maps to delineate individual thalamic nuclei, then extract the tractography profiles for each and calculate the voxel-wise tractography gradients. Within each thalamic nucleus, the tractography gradients were topographically arranged as distinct non-overlapping cortical networks with transitory overlapping mid-zones. This work significantly advances quantitative segmentation of the thalamus in vivo using 3T MRI. At an individual subject level, the thalamic segmentations consistently achieve a close relationship with a priori histological atlas information, and resolve in vivo topographic gradients within each thalamic nucleus for the first time. Additionally, these techniques allow individual thalamic nuclei to be closely aligned across large populations and generate measures of inter-individual variability that can be used to study both basic function and pathological processes in vivo.
Topics: Adult; Brain Mapping; Diffusion Tensor Imaging; Female; Humans; Image Processing, Computer-Assisted; Male; Neural Pathways; Thalamic Nuclei
PubMed: 27639355
DOI: 10.1016/j.neuroimage.2016.08.028 -
European Journal of Histochemistry : EJH Mar 2022The thalamic reticular nucleus (TRN) projects inhibitory signals to the thalamus, thereby controlling thalamocortical connections. Few studies have examined the...
The thalamic reticular nucleus (TRN) projects inhibitory signals to the thalamus, thereby controlling thalamocortical connections. Few studies have examined the development of TRN projections to the anterior thalamic nuclei with regard to axon course and the axon terminal distributions. In the present study, we used parvalbumin (PV) immunostaining to investigate inhibitory projections from the TRN to the thalamus in postnatal (P) 2- to 5-week-old rats (P14-35). The distribution of PV-positive (+) nerve fibers and nerve terminals markedly differed among the anterior thalamic nuclei at P14. Small, beaded nerve terminals were more distributed throughout the anterodorsal nucleus (AD) than in the anteroventral nucleus (AV) and anteromedial nucleus (AM). PV+ fibers traveling from the TRN to the AD were observed in the AV and AM. Nodular nerve terminals, spindle or en passant terminals, were identified on the axons passing through the AV and AM. At P21, axon bundles traveling without nodular terminals were observed, and nerve terminals were distributed throughout the AV and AM similar to the AD. At P28 and P35, the nerve terminals were evenly distributed throughout each nucleus. In addition, DiI tracer injections into the retrosplenial cortex revealed retrogradely-labeled projection neurons in the 3 nuclei at P14. At P14, the AD received abundant projections from the TRN and then projected to the retrosplenial cortex. The AV and AM seem to receive projections with distinct nodular nerve terminals from the TRN and project to the retrosplenial cortex. The projections from TRN to the AV and AM with nodular nerve terminals at P14 are probably developmental-period specific. In comparison, the TRN projections to the AD at P14 might be related to the development of spatial navigation as part of the head orientation system.
Topics: Animals; Anterior Thalamic Nuclei; Rats; Thalamic Nuclei
PubMed: 35330554
DOI: 10.4081/ejh.2022.3370 -
Brain and Language Jul 2013Thalamic nuclei associated with language including the ventral lateral, ventral anterior, intralaminar and mediodorsal form a hub that uniquely receives the output of... (Review)
Review
Thalamic nuclei associated with language including the ventral lateral, ventral anterior, intralaminar and mediodorsal form a hub that uniquely receives the output of the basal ganglia and cerebellum, and is connected with frontal (premotor and prefrontal) cortices through two parallel circuits: a thalamic pathway targets the middle frontal cortical layers focally, and the other innervates widely cortical layer 1, poised to recruit other cortices and thalamic nuclei for complex cognitive operations. Return frontal pathways to the thalamus originate from cortical layers 6 and 5. Information through this integrated thalamo-cortical system is gated by the inhibitory thalamic reticular nucleus and modulated by dopamine, representing a specialization in primates. The intricate dialogue of distinct thalamic nuclei with the basal ganglia, cerebellum, and specific dorsolateral prefrontal and premotor cortices associated with language, suggests synergistic roles in the complex but seemingly effortless sequential transformation of cognitive operations for speech production in humans.
Topics: Frontal Lobe; Humans; Language; Neural Pathways; Speech; Thalamic Nuclei
PubMed: 23211411
DOI: 10.1016/j.bandl.2012.10.001