scholarly journals Aspects of gorgonopsian paleobiology and evolution: insights from the basicranium, occiput, osseous labyrinth, vasculature, and neuroanatomy

2017 ◽  
Author(s):  
Ricardo M Araujo ◽  
Vincent Fernandez ◽  
Michael J Polcyn ◽  
Jörg Fröbisch ◽  
Rui M.S. Martins
Keyword(s):  
Semicircular Canal ◽  
Phase Contrast ◽  
Cranial Nerves ◽  
Detailed Examination ◽  
Micro Computed Tomography ◽  
Horizontal Semicircular Canal ◽  
The Past ◽  
Architectural Constraints ◽  
The Brain ◽  
Immature Specimen

Synapsida, the clade including therapsids and thus also mammals, is one of the two major branches of amniotes. Organismal design, with modularity as a concept, offers insights into the evolution of therapsids, a group that experienced profound anatomical transformations throughout the past 270Ma, eventually leading to the evolution of the mammalian bauplan. However, the anatomy of some therapsid groups remains obscure. Gorgonopsian braincase anatomy is poorly known and many anatomical aspects of the brain, cranial nerves, vasculature, and osseous labyrinth, remain unclear. We analyzed two gorgonopsian specimens, GPIT/RE/7124 and GPIT/RE/7119, using propagation phase contrast synchrotron micro-computed tomography. The lack of fusion between many basicranial and occipital bones in the immature specimen GPIT/RE/7124 allowed us to reconstruct its anatomy and ontogenetic sequence in comparison with the mature GPIT/RE/7119. We examined the braincase and rendered various skull cavities. Notably, there is a separate ossification between what was previously referred to as the “parasphenoid” and the basioccipital. We reinterpreted this element as a posterior ossification of the basisphenoid: the basipostsphenoid. Moreover, the “parasphenoid” is a co-ossification of the dermal parasphenoid and the endochondral basipresphenoid. Our detailed examination of the osseous labyrinth reveals a unique discoid, rather than toroidal, morphology of the horizontal semicircular canal that probably results from architectural constraints of the opisthotic and supraoccipital ossifications. In addition, the orientation of the horizontal semicircular canal suggests that gorgonopsians had an anteriorly tilted alert head posture. The morphology of the brain endocast is in accordance with the more reptilian endocast shape of other non-mammaliaform neotherapsids.

scholarly journals Aspects of gorgonopsian paleobiology and evolution: insights from the basicranium, occiput, osseous labyrinth, vasculature, and neuroanatomy

2017 ◽  
Author(s):  
Ricardo M Araujo ◽  
Vincent Fernandez ◽  
Michael J Polcyn ◽  
Jörg Fröbisch ◽  
Rui M.S. Martins
Keyword(s):  
Semicircular Canal ◽  
Phase Contrast ◽  
Cranial Nerves ◽  
Detailed Examination ◽  
Micro Computed Tomography ◽  
Horizontal Semicircular Canal ◽  
The Past ◽  
Architectural Constraints ◽  
The Brain ◽  
Immature Specimen

Synapsida, the clade including therapsids and thus also mammals, is one of the two major branches of amniotes. Organismal design, with modularity as a concept, offers insights into the evolution of therapsids, a group that experienced profound anatomical transformations throughout the past 270Ma, eventually leading to the evolution of the mammalian bauplan. However, the anatomy of some therapsid groups remains obscure. Gorgonopsian braincase anatomy is poorly known and many anatomical aspects of the brain, cranial nerves, vasculature, and osseous labyrinth, remain unclear. We analyzed two gorgonopsian specimens, GPIT/RE/7124 and GPIT/RE/7119, using propagation phase contrast synchrotron micro-computed tomography. The lack of fusion between many basicranial and occipital bones in the immature specimen GPIT/RE/7124 allowed us to reconstruct its anatomy and ontogenetic sequence in comparison with the mature GPIT/RE/7119. We examined the braincase and rendered various skull cavities. Notably, there is a separate ossification between what was previously referred to as the “parasphenoid” and the basioccipital. We reinterpreted this element as a posterior ossification of the basisphenoid: the basipostsphenoid. Moreover, the “parasphenoid” is a co-ossification of the dermal parasphenoid and the endochondral basipresphenoid. Our detailed examination of the osseous labyrinth reveals a unique discoid, rather than toroidal, morphology of the horizontal semicircular canal that probably results from architectural constraints of the opisthotic and supraoccipital ossifications. In addition, the orientation of the horizontal semicircular canal suggests that gorgonopsians had an anteriorly tilted alert head posture. The morphology of the brain endocast is in accordance with the more reptilian endocast shape of other non-mammaliaform neotherapsids.

scholarly journals Aspects of gorgonopsian paleobiology and evolution: insights from the basicranium, occiput, osseous labyrinth, vasculature, and neuroanatomy

PeerJ ◽  
2017 ◽  
Vol 5 ◽  
pp. e3119 ◽  
Author(s):  
Ricardo Araújo ◽  
Vincent Fernandez ◽  
Michael J. Polcyn ◽  
Jörg Fröbisch ◽  
Rui M.S. Martins
Keyword(s):  
Semicircular Canal ◽  
Phase Contrast ◽  
Cranial Nerves ◽  
Micro Computed Tomography ◽  
Horizontal Semicircular Canal ◽  
Lack Of Fusion ◽  
The Past ◽  
Architectural Constraints ◽  
The Brain ◽  
Immature Specimen

Synapsida, the clade including therapsids and thus also mammals, is one of the two major branches of amniotes. Organismal design, with modularity as a concept, offers insights into the evolution of therapsids, a group that experienced profound anatomical transformations throughout the past 270 Ma, eventually leading to the evolution of the mammalian bauplan. However, the anatomy of some therapsid groups remains obscure. Gorgonopsian braincase anatomy is poorly known and many anatomical aspects of the brain, cranial nerves, vasculature, and osseous labyrinth, remain unclear. We analyzed two gorgonopsian specimens, GPIT/RE/7124 and GPIT/RE/7119, using propagation phase contrast synchrotron micro-computed tomography. The lack of fusion between many basicranial and occipital bones in GPIT/RE/7124, which is an immature specimen, allowed us to reconstruct its anatomy and ontogenetic sequence, in comparison with the mature GPIT/RE/7119, in great detail. We explored the braincase and rendered various skull cavities. Notably, we found that there is a separate ossification between what was previously referred to as the “parasphenoid” and the basioccipital. We reinterpreted this element as a posterior ossification of the basisphenoid: the basipostsphenoid. Moreover, we show that the previously called “parasphenoid” is in fact the co-ossification of the dermal parasphenoid and the endochondral basipresphenoid. In line with previous descriptions, the anatomy of the osseous labyrinth is rendered in detail, revealing a unique discoid morphology of the horizontal semicircular canal, rather than toroidal, probably due to architectural constraints of the ossification of the opisthotic and supraoccipital. In addition, the orientation of the horizontal semicircular canal suggests that gorgonopsians had an anteriorly tilted alert head posture. The morphology of the brain endocast is in accordance with the more reptilian endocast shape of other non-mammaliaform neotherapsids.

scholarly journals Aspects of the gorgonopsian paleobiology: insights from the basicranium, occiput, osseous labyrinth and neuroanatomy of the immature gorgonopsian skull of Aloposaurus gracilis (Therapsida: Theriodontia: Gorgonopsia)

2016 ◽  
Author(s):  
Ricardo M Araujo ◽  
Vincent Fernandez ◽  
Michael J Polcyn ◽  
Jörg Fröbisch ◽  
Rui M.S. Martins
Keyword(s):  
Computed Tomography ◽  
Semicircular Canal ◽  
Phase Contrast ◽  
Cranial Nerves ◽  
Brain Anatomy ◽  
Micro Computed Tomography ◽  
Horizontal Semicircular Canal ◽  
Head Posture ◽  
The Past ◽  
The Brain

Synapsida, the clade including therapsids and thus also mammals, is one of the two major branches of amniotes. Organismal design, with modularity as a concept, offers insights into the evolution of therapsids, a group that experienced profound anatomical transformations throughout the past 270Ma, eventually leading to the evolution of the mammalian bauplan. However, the anatomy of some therapsid groups remains obscure. Gorgonopsian braincase anatomy remains poorly known, and aspects of their brain anatomy, cranial nerves and vasculature, osseous labyrinth persist unknown. By using propagation phase contrast synchrotron micro-computed tomography, we scanned GPIT/RE/7124, a specimen previously reported as Aloposaurus gracilis. We explored the anatomy of the braincase and rendered the anatomy of the various skull cavities. Notably, we found that there is a separate ossification between what was previously referred as the “parasphenoid” and the basioccipital. This element is reinterpreted as a posterior ossification of the basisphenoid, the basi-postsphenoid. Additionally the previously called “parasphenoid” is in fact the co-ossification of the dermal parasphenoid and the endochondral basi-presphenoid. The anatomy of the osseous labyrinth is rendered in detail, revealing a unique discoid morphology of the horizontal semicircular canal, rather than toroidal, probably due to architectural contraints of the ossification of the opisthotic and supraoccipital. In addition, the orientation of the horizontal semicircular canal suggests an anteriorly tilted alert head posture. The morphology of the brain endocast is in accordance with the more reptilian endocast shape of other non-mammaliaform neotherapsids.

scholarly journals Ontogenetic braincase development in Psittacosaurus lujiatunensis (Dinosauria: Ceratopsia) using micro-computed tomography

PeerJ ◽  
2019 ◽  
Vol 7 ◽  
pp. e7217 ◽  
Author(s):  
Claire M. Bullar ◽  
Qi Zhao ◽  
Michael J. Benton ◽  
Michael J. Ryan
Keyword(s):  
Computed Tomography ◽  
Semicircular Canal ◽  
Morphological Changes ◽  
Relative Reduction ◽  
Growth Stages ◽  
Ontogenetic Changes ◽  
Micro Computed Tomography ◽  
Horizontal Semicircular Canal ◽  
Computed Tomography Scans ◽  
Key Events

Ontogenetic sequences are relatively rare among dinosaurs, with Ceratopsia being one of the better represented clades, and especially among geologically earlier forms, such as Psittacosaurus. Psittacosaurus is a small, bipedal basal ceratopsian abundant in the Lower Cretaceous deposits of Asia, whose cranial and endocranial morphology has been well studied, but only cursory details have been published on the bones surrounding the brain. Using reconstructions created from micro-computed tomography scans of well-preserved skulls from the Barremian–Aptian Yixian Formation, China, we document morphological changes in the braincase of Psittacosaurus lujiatunensis through three growth stages, hatchling, juvenile, and adult, thus providing the first detailed study of ceratopsian braincase morphology through ontogeny. Notable ontogenetic changes in the braincase of P. lujiatunensis include a dramatic relative reduction in size of the supraoccipital, an increase in the lateral expansion of the paroccipital processes and a decrease in the angle between the lateral semicircular canal and the palatal plane. These ontogenetic morphological changes in the braincase relate to expansion of the cranium and brain through growth, as well as reflecting the switch from quadrupedal juveniles to bipedal adults as documented in the changing orientation of the horizontal semicircular canal through ontogeny. Recognition of these patterns in a basal ceratopsian has implications for understanding key events in later ceratopsian evolution, such as the development of the parieto-squamosal frill in derived neoceratopsians.

Quantitive studies of the reactions to horizontal angular accelerations in axolotls. II. head-turning reflexes in animals with a supernumerary pair of labyrinths

1977 ◽  
Vol 66 (1) ◽  
pp. 15-31
Author(s):  
K. Brandle
Keyword(s):  
Linear Relationship ◽  
Semicircular Canal ◽  
Time Course ◽  
Reaction Threshold ◽  
Head Turning ◽  
Horizontal Semicircular Canal ◽  
Reference Parameter ◽  
Intensity Functions ◽  
The Relationship ◽  
The Brain

In axolotls (Ambystoma mexicanun) the labyrinths and the associated parts of the medulla were doubled artificially. In these so-called tandem-heads the vestibular afferent fibres from both labyrinths on one side united within the medulla to form common bundles. The head-turning reflexes following impulse acceleration and during long-lasting acceleration were measured quantitatively and compared with those for normal animals. The form and the time-course of the reactions were almost identical in both groups. Tandem-heads showed a linear relationship between stimulus intensity and reaction strength, parallel to that in normal animals but with a greater reaction for a given stimulus. Consequent to this shift in the relationship, there was a significant decrease in the reaction threshold. The removal of one horizontal semicircular canal in tandem-heads proved that both pairs of labyrinths were functionally connected with the brain. It was suggested that during ontogenesis there exists a kind of specificity in the connexion of vestibular fibres. From the parallel shift of the intensity functions it was concluded that the input from both pairs of labyrinths in tandem-heads is not simply accumulate but compared with a reference parameter, which is also double in tandem-heads.

Prognosis and Horizontal Semicircular Canal Function in HC-BPPV

2005 ◽  
Vol 64 (6) ◽  
pp. 479-483 ◽  
Author(s):  
Nobuya Fujita ◽  
Toshiaki Yamanaka ◽  
Hideyuki Okamoto ◽  
Takayuki Murai ◽  
Hiroshi Hosoi
Keyword(s):  
Semicircular Canal ◽  
Horizontal Semicircular Canal

Neuro-Clinical Signatures of Language Impairments: A Theoretical Framework for Function-to-structure Mapping in Clinics

2020 ◽  
Vol 20 (9) ◽  
pp. 800-811 ◽  
Author(s):  
Ferath Kherif ◽  
Sandrine Muller
Keyword(s):  
Brain Mapping ◽  
Theoretical Framework ◽  
Brain Regions ◽  
Language Impairments ◽  
Structure Mapping ◽  
Language Functions ◽  
The Past ◽  
Language Recovery ◽  
The Brain ◽  
Bow Tie

In the past decades, neuroscientists and clinicians have collected a considerable amount of data and drastically increased our knowledge about the mapping of language in the brain. The emerging picture from the accumulated knowledge is that there are complex and combinatorial relationships between language functions and anatomical brain regions. Understanding the underlying principles of this complex mapping is of paramount importance for the identification of the brain signature of language and Neuro-Clinical signatures that explain language impairments and predict language recovery after stroke. We review recent attempts to addresses this question of language-brain mapping. We introduce the different concepts of mapping (from diffeomorphic one-to-one mapping to many-to-many mapping). We build those different forms of mapping to derive a theoretical framework where the current principles of brain architectures including redundancy, degeneracy, pluri-potentiality and bow-tie network are described.

Chemo- and Optogenetic Strategies for the Elucidation of Pain Pathways

2019 ◽  
pp. 816-832 ◽  
Author(s):  
Sascha R. A. Alles ◽  
Anne-Marie Malfait ◽  
Richard J. Miller
Keyword(s):  
Chronic Pain ◽  
Pain Response ◽  
Conscious Perception ◽  
Novel Therapies ◽  
The Past ◽  
Nociceptive Pathways ◽  
Pain Pathways ◽  
Technical Advances ◽  
The Brain

Pain is not a simple phenomenon and, beyond its conscious perception, involves circuitry that allows the brain to provide an affective context for nociception, which can influence mood and memory. In the past decade, neurobiological techniques have been developed that allow investigators to elucidate the importance of particular groups of neurons in different aspects of the pain response, something that may have important translational implications for the development of novel therapies. Chemo- and optogenetics represent two of the most important technical advances of recent times for gaining understanding of physiological circuitry underlying complex behaviors. The use of these techniques for teasing out the role of neurons and glia in nociceptive pathways is a rapidly growing area of research. The major findings of studies focused on understanding circuitry involved in different aspects of nociception and pain are highlighted in this article. In addition, attention is drawn to the possibility of modification of chemo- and optogenetic techniques for use as potential therapies for treatment of chronic pain disorders in human patients.

Examination of the cupula and stereocilia of the horizontal semicircular canal in the toadfishOpsanus tau

1998 ◽  
Vol 402 (1) ◽  
pp. 48-61 ◽  
Author(s):  
Robert B. Silver ◽  
Anthony P. Reeves ◽  
Antionette Steinacker ◽  
Stephen M. Highstein
Keyword(s):  
Semicircular Canal ◽  
Horizontal Semicircular Canal

scholarly journals DNA Methylation Profiles of Tph1A and BDNF in Gut and Brain of L. Rhamnosus-Treated Zebrafish

Biomolecules ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 142
Author(s):  
Mariella Cuomo ◽  
Luca Borrelli ◽  
Rosa Della Monica ◽  
Lorena Coretti ◽  
Giulia De Riso ◽  
...  
Keyword(s):  
Dna Methylation ◽  
Molecular Mechanisms ◽  
The Past ◽  
Targeted Analysis ◽  
Lack Of Information ◽  
High Resolution Power ◽  
Resolution Level ◽  
Health And Disease ◽  
High Doses ◽  
The Brain

The bidirectional microbiota–gut–brain axis has raised increasing interest over the past years in the context of health and disease, but there is a lack of information on molecular mechanisms underlying this connection. We hypothesized that change in microbiota composition may affect brain epigenetics leading to long-lasting effects on specific brain gene regulation. To test this hypothesis, we used Zebrafish (Danio Rerio) as a model system. As previously shown, treatment with high doses of probiotics can modulate behavior in Zebrafish, causing significant changes in the expression of some brain-relevant genes, such as BDNF and Tph1A. Using an ultra-deep targeted analysis, we investigated the methylation state of the BDNF and Tph1A promoter region in the brain and gut of probiotic-treated and untreated Zebrafishes. Thanks to the high resolution power of our analysis, we evaluated cell-to-cell methylation differences. At this resolution level, we found slight DNA methylation changes in probiotic-treated samples, likely related to a subgroup of brain and gut cells, and that specific DNA methylation signatures significantly correlated with specific behavioral scores.

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