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Frontiers in Behavioral Neuroscience 2022The midline and intralaminar nuclei of the thalamus form a major part of the "limbic thalamus;" that is, thalamic structures anatomically and functionally linked with...
The midline and intralaminar nuclei of the thalamus form a major part of the "limbic thalamus;" that is, thalamic structures anatomically and functionally linked with the limbic forebrain. The midline nuclei consist of the paraventricular (PV) and paratenial nuclei, dorsally and the rhomboid and nucleus reuniens (RE), ventrally. The rostral intralaminar nuclei (ILt) consist of the central medial (CM), paracentral (PC) and central lateral (CL) nuclei. We presently concentrate on RE, PV, CM and CL nuclei of the thalamus. The nucleus reuniens receives a diverse array of input from limbic-related sites, and predominantly projects to the hippocampus and to "limbic" cortices. The RE participates in various cognitive functions including spatial working memory, executive functions (attention, behavioral flexibility) and affect/fear behavior. The PV receives significant limbic-related afferents, particularly the hypothalamus, and mainly distributes to "affective" structures of the forebrain including the bed nucleus of stria terminalis, nucleus accumbens and the amygdala. Accordingly, PV serves a critical role in "motivated behaviors" such as arousal, feeding/consummatory behavior and drug addiction. The rostral ILt receives both limbic and sensorimotor-related input and distributes widely over limbic and motor regions of the frontal cortex-and throughout the dorsal striatum. The intralaminar thalamus is critical for maintaining consciousness and directly participates in various sensorimotor functions (visuospatial or reaction time tasks) and cognitive tasks involving striatal-cortical interactions. As discussed herein, while each of the midline and intralaminar nuclei are anatomically and functionally distinct, they collectively serve a vital role in several affective, cognitive and executive behaviors - as major components of a brainstem-diencephalic-thalamocortical circuitry.
PubMed: 36082310
DOI: 10.3389/fnbeh.2022.964644 -
Vision Research Sep 2021Rubin's face-vase illusion demonstrates how one can switch back and forth between two different interpretations depending on how the figure outlines are assigned. In the...
Rubin's face-vase illusion demonstrates how one can switch back and forth between two different interpretations depending on how the figure outlines are assigned. In the primate visual system, assigning ownership along figure borders is encoded by neurons called the border ownership (BO) cells. Studies show that the responses of these neurons not only depend on the local features within their receptive fields, but also on contextual information. Despite two decades of studies on BO neurons, the ownership assignment mechanism in the brain is still unknown. Here, we propose a hierarchical recurrent model grounded on the hypothesis that neurons in the dorsal stream provide the context required for ownership assignment. Our proposed model incorporates early recurrence from the dorsal pathway as well as lateral modulations within the ventral stream. While dorsal modulations initiate the response difference to figure on either side of the border, lateral modulations enhance the difference. We found responses of our dorsally-modulated BO cells, similar to their biological counterparts, are invariant to size, position and solid/outlined figures. Moreover, our model BO cells exhibit comparable levels of reliability in the ownership signal to biological BO neurons. We found dorsal modulations result in high levels of accuracy and robustness for BO assignments in complex scenes compared to previous models based on ventral feedback. Finally, our experiments with illusory contours suggest that BO encoding could explain the perception of such contours in higher processing stages in the brain.
Topics: Animals; Ownership; Pattern Recognition, Visual; Photic Stimulation; Reproducibility of Results; Visual Cortex
PubMed: 34023589
DOI: 10.1016/j.visres.2021.04.009 -
Annales de Chirurgie Plastique Et... Aug 2021Rhinoplasty is one of the most commonly performed aesthetic surgeries among patients who are admitted to plastic surgeons. Recent research has focused on dorsal...
PURPOSE
Rhinoplasty is one of the most commonly performed aesthetic surgeries among patients who are admitted to plastic surgeons. Recent research has focused on dorsal preservation in hump reduction and consequently dorsal preservation techniques have become more popular. The current study aimed to revise the push down technique by adding ostectomy.
PATIENTS AND METHODS
In the present retrospective study, data from patients who underwent rhinoplasty to fix a nasal hump were assessed. All patients were administered the push down technique with ostectomy. Following these inclusion and exclusion criteria, the records of 52 patients were assessed (45 females and 7 males). The median age of the patients was 22.2 years. Patients were evaluated using the "Rhinoplasty Outcome Evaluation" (ROE) questionnaire both before surgery and 12 months after surgery. The follow-up period ranged between 13 and 21 months (median of 15.1 months).
RESULTS
Patients were evaluated before surgery and after one year of surgery by the ROE scale. The median of the ROE score before surgery was 63.4. The median score after one year of surgery was 91.6. Thus, the ROE score significantly increased 12 months after surgery (P<0.001).
CONCLUSIONS
This study was the first to demonstrate the benefits of performing the push down technique with ostectomy in terms of obtaining a wider nasal cavity. In addition, it can be assumed that the disadvantage of using the push down technique can be overcome with ostectomy.
Topics: Adult; Esthetics; Female; Humans; Male; Nasal Septum; Plastic Surgery Procedures; Retrospective Studies; Rhinoplasty; Young Adult
PubMed: 32978019
DOI: 10.1016/j.anplas.2020.08.004 -
Movement Disorders : Official Journal... Feb 2021The aim of this study is to identify anatomical regions related to stimulation-induced dyskinesia (SID) after pallidal deep brain stimulation (DBS) in Parkinson's...
OBJECTIVES
The aim of this study is to identify anatomical regions related to stimulation-induced dyskinesia (SID) after pallidal deep brain stimulation (DBS) in Parkinson's disease (PD) patients and to analyze connectivity associated with SID.
METHODS
This retrospective study analyzed the clinical and imaging data of PD patients who experienced SID during the monopolar review after pallidal DBS. We analyzed structural and functional connectivity using normative connectivity data with the volume of tissue activated (VTA) modeling. Each contact was assigned to either that producing SID (SID VTA) or that without SID (non-SID VTA). Structural and functional connectivity was compared between SID and non-SID VTAs. "Optimized VTAs" were also estimated using the DBS settings at 6 months after implantation.
RESULTS
Of the 68 consecutive PD patients who underwent pallidal implantation, 20 patients (29%) experienced SID. SID VTAs were located more dorsally and anteriorly compared with non-SID and optimized VTAs and were primarily in the dorsal globus pallidus internus (GPi) and dorsal globus pallidus externus (GPe). SID VTAs showed significantly higher structural connectivity than non-SID VTAs to the associative cortex and supplementary motor area/premotor cortex (P < 0.0001). Simultaneously, non-SID VTAs showed greater connectivity to the primary sensory cortex, cerebellum, subthalamic nucleus, and motor thalamus (all P < 0.0004). Functional connectivity analysis showed significant differences between SID and non-SID VTAs in multiple regions, including the primary motor, premotor, and prefrontal cortices and cerebellum.
CONCLUSION
SID VTAs were primarily in the dorsal GPi/GPe. The connectivity difference between the motor-related cortices and subcortical regions may explain the presence and absence of SID. © 2020 International Parkinson and Movement Disorder Society.
Topics: Deep Brain Stimulation; Dyskinesias; Globus Pallidus; Humans; Parkinson Disease; Retrospective Studies
PubMed: 33002233
DOI: 10.1002/mds.28324 -
Journal of Morphology Nov 2023Leposternon microcephalum is a species belonging to the Amphisbaenia, a group of burrowing reptiles. Amphisbaenia present various morphological and physiological...
Leposternon microcephalum is a species belonging to the Amphisbaenia, a group of burrowing reptiles. Amphisbaenia present various morphological and physiological adaptations that allow them to penetrate the ground and live underground, through a system of galleries and permanent chambers that they build themselves. Among the morphological adaptations in this group, those of the skull stand out as it serves as the main excavation tool. Four basic skull shapes are recognized: rounded, keeled, shovel-shaped, and spade-shaped. The skull of L. microcephalum belongs to this last type, which is considered the most specialized. The species inhabits soils that are highly compacted and difficult to penetrate. Among the species of Leposternon present in South America, L. microcephalum has the widest distribution, being found in all Brazilian biomes and neighboring countries such as Bolivia, Argentina, Paraguay, and Uruguay. The analysis of the skull of this species was carried out using three-dimensional geometric morphometrics (3D-GMM), a technique that allows comparative analysis, through robust statistical methods, of shape and its variations, using Cartesian coordinate data from a configuration of homologous landmarks. The technique allows the size and shape components of a structure to be analyzed separately. From an ontogenetic point of view, this methodology had also been used to investigate variations in Cynisca leucura, a member of the Amphisbaenidae with a rounded head. Our hypothesis is that the patterns of morphological differentiation in the skull, mainly in the intermediate and occipital regions, are similar in different Amphisbaenia species. Therefore, the objective of this study was to analyze cranial morphological variations in an ontogenetic series of L. microcephalum using 3D-GMM. Computed Tomographic scans of 13 specimens were analyzed: juveniles (N = 8) and adults (N = 5), based on 20 landmarks that characterize the skull. Principal components and regression analyses between shape (dependent variable) and size (independent variable) showed a clear difference between the cranial morphological pattern of juvenile individuals and that of adults. For instance, young specimens tend to have a dorsoventrally tall neurocranium, with the tip of the snout more anteriorly oriented and its dorsal border subtly curved. Dorsally, the parietal region is thicker and smoothly dome-shaped in juveniles. As in C. leucura, the variation was strongly correlated with the size change from juvenile to adult, indicating a dominant role for ontogenetic allometry in determining skull shape.
Topics: Humans; Animals; Skull; Head; Regression Analysis; Lizards; Brazil
PubMed: 37856276
DOI: 10.1002/jmor.21643 -
ELife May 2022The dorsal axial muscles, or epaxial muscles, are a fundamental structure covering the spinal cord and vertebrae, as well as mobilizing the vertebrate trunk. To date,...
The dorsal axial muscles, or epaxial muscles, are a fundamental structure covering the spinal cord and vertebrae, as well as mobilizing the vertebrate trunk. To date, mechanisms underlying the morphogenetic process shaping the epaxial myotome are largely unknown. To address this, we used the medaka -enhancer mutant (), which exhibits ventralized dorsal trunk structures resulting in impaired epaxial myotome morphology and incomplete coverage over the neural tube. In wild type, dorsal dermomyotome (DM) cells reduce their proliferative activity after somitogenesis. Subsequently, a subset of DM cells, which does not differentiate into the myotome population, begins to form unique large protrusions extending dorsally to guide the epaxial myotome dorsally. In , by contrast, DM cells maintain the high proliferative activity and mainly form small protrusions. By combining RNA- and ChIP-sequencing analyses, we revealed direct targets of Zic1, which are specifically expressed in dorsal somites and involved in various aspects of development, such as cell migration, extracellular matrix organization, and cell-cell communication. Among these, we identified as a crucial factor regulating both cell proliferation and protrusive activity of DM cells. We propose that dorsal extension of the epaxial myotome is guided by a non-myogenic subpopulation of DM cells and that empowers the DM cells to drive the coverage of the neural tube by the epaxial myotome.
Topics: Animals; Embryonic Development; Gene Expression Regulation, Developmental; Morphogenesis; Oryzias; Somites; Wnt Proteins
PubMed: 35522214
DOI: 10.7554/eLife.71845 -
Injury Dec 2022Hand wounds account for 35 to 51% of hand traumas. Damage to underlying anatomical structures depends on the location of the wound. The objective of this study is to...
INTRODUCTION
Hand wounds account for 35 to 51% of hand traumas. Damage to underlying anatomical structures depends on the location of the wound. The objective of this study is to describe the topographic distribution of hand wounds allowing for subsequent evaluation of the link between affected surface area and underlying lesion.
METHODS
We retrospectively reviewed the medical records of 1058 patients with a total of 1319 wounds over a period of 2 years. Wound location was described according to the cutaneous projection of IFSSH zones for flexors and extensors. Any associated deep lesions were evaluated. Topographical distribution was modeled graphically using a heat-map. We compared the proportion of underlying lesions between each cutaneous zone. Sub-group analysis for lesions' rate regarding zone groups were performed.
RESULTS
58.9% of wounds were located on the palmar surface and 41.1% on the dorsal surface. 71% of wounds affected only the digits. The index finger was the most affected. The most damaged region was zone 2 for palmar wounds and zone 3 for dorsal wounds. 45.5% of wounds resulted in injury to a significant underlying anatomical structure. This frequency was 36.4% and 58.5% for palmar and dorsal wounds respectively. More than 50% of wounds in palmar zone 5 and dorsal zones 1, 3, 5, 6 and 7 presented at least one lesion. A lesion of major structure was more frequently found in palmar zone 5 (p <0.001). Dorsally, no zone predominated. Subgroup analysis for dorsal wounds revealed that wounds overlying joints had more major lesions including more tendons injuries and more articular violations with zone 3 presenting a rate of 68%.
CONCLUSION
We provided the first graphical representation for the topographical distribution of hand wounds. Dorsal wounds have a higher association with injury to underlying structures. These results generally support surgical exploration of all hand wounds regardless of their location.
LEVEL OF EVIDENCE
IV Study type: Epidemiological study.
Topics: Humans; Retrospective Studies; Hand Injuries; Tendon Injuries; Hand; Upper Extremity
PubMed: 36424689
DOI: 10.1016/j.injury.2022.10.022 -
Neuromodulation : Journal of the... Aug 2023In the practice of intrathecal drug delivery, consensus exists regarding the cephalad to caudad location of the catheter tip relative to dermatomal distribution of pain.... (Clinical Trial)
Clinical Trial
OBJECTIVES
In the practice of intrathecal drug delivery, consensus exists regarding the cephalad to caudad location of the catheter tip relative to dermatomal distribution of pain. However, data are lacking on the importance of dorsal vs ventral tip location relative to the spinal cord. We hypothesize that a dorsally placed catheter tip improves efficacy because of closer proximity to nociceptive pathways.
MATERIALS AND METHODS
A retrospective review of 298 patients with cancer with intrathecal drug delivery systems implanted at the Huntsman Cancer Institute from May 2014 to June 2020 was performed. Patients were stratified by catheter tip location zones based on available radiographic studies. Patient-controlled intrathecal medication dose requirements and rate of change were compared with catheter zone and other variables, including the presence of adjuncts such as bupivacaine and ziconotide.
RESULTS
A total of 158 patients were suitable for analysis demonstrating a dorsal tip in 63.9% (n = 101) and ventral tip in 36.1% (n = 57), with a median follow-up of 17 days (interquartile range [IQR], 10-24). There was no difference in daily dose change from implant to discharge between the dorsal group 8.2% (IQR, 0.0-41.5) and ventral group 20.8% (IQR, 0.0-66.7; p = 0.12). Daily dose change from discharge to follow-up was 2.6% (IQR, 0.0-7.1) in the dorsal group and 1.8% (IQR, 0.0-5.7) in the ventral group (p = 0.92). Catheter tip location had no impact on systemic opioid use.
CONCLUSIONS
We did not find significant associations between dorsal vs ventral catheter tip location and measures of pain relief, including change in intrathecal dose or systemic opioid use.
Topics: Humans; Analgesics, Opioid; Cancer Pain; Catheters; Injections, Spinal; Neoplasms; Opioid-Related Disorders; Pain
PubMed: 35393238
DOI: 10.1016/j.neurom.2022.02.230 -
Journal of Anatomy Jul 2021Although the development of the sympathetic trunks was first described >100 years ago, the topographic aspect of their development has received relatively little...
Although the development of the sympathetic trunks was first described >100 years ago, the topographic aspect of their development has received relatively little attention. We visualised the sympathetic trunks in human embryos of 4.5-10 weeks post-fertilisation, using Amira 3D-reconstruction and Cinema 4D-remodelling software. Scattered, intensely staining neural crest-derived ganglionic cells that soon formed longitudinal columns were first seen laterally to the dorsal aorta in the cervical and upper thoracic regions of Carnegie stage (CS)14 embryos. Nerve fibres extending from the communicating branches with the spinal cord reached the trunks at CS15-16 and became incorporated randomly between ganglionic cells. After CS18, ganglionic cells became organised as irregular agglomerates (ganglia) on a craniocaudally continuous cord of nerve fibres, with dorsally more ganglionic cells and ventrally more fibres. Accordingly, the trunks assumed a "pearls-on-a-string" appearance, but size and distribution of the pearls were markedly heterogeneous. The change in position of the sympathetic trunks from lateral (para-aortic) to dorsolateral (prevertebral or paravertebral) is a criterion to distinguish the "primary" and "secondary" sympathetic trunks. We investigated the position of the trunks at vertebral levels T2, T7, L1 and S1. During CS14, the trunks occupied a para-aortic position, which changed into a prevertebral position in the cervical and upper thoracic regions during CS15, and in the lower thoracic and lumbar regions during CS18 and CS20, respectively. The thoracic sympathetic trunks continued to move further dorsally and attained a paravertebral position at CS23. The sacral trunks retained their para-aortic and prevertebral position, and converged into a single column in front of the coccyx. Based on our present and earlier morphometric measurements and literature data, we argue that differential growth accounts for the regional differences in position of the sympathetic trunks.
Topics: Embryo, Mammalian; Embryonic Development; Humans; Sympathetic Nervous System
PubMed: 33641166
DOI: 10.1111/joa.13415