Excitatory/inhibitory response types in the cochlear nucleus: relationships to discharge patterns and responses to electrical stimulation of the auditory nerve

1985 ◽  
Vol 54 (4) ◽  
pp. 917-939 ◽  
Author(s):  
W. P. Shofner ◽  
E. D. Young
Keyword(s):  
Receptive Field ◽  
Cochlear Nucleus ◽  
Auditory Nerve ◽  
Type I ◽  
Type Ii ◽  
Type Iii ◽  
Rate Level ◽  
Cochlear Nucleus Units ◽  
Excitatory Responses ◽  
Discharge Patterns

We have studied the response properties of single units in the cochlear nucleus of unanesthetized decerebrate cats. The purpose of the study was to compare the properties of cochlear nucleus units as described in two commonly used classification schemes. Units were first classified according to their receptive-field properties based on the relative prominence of excitatory and inhibitory responses to tones and noise. Units were then classified on the basis of their discharge patterns to short tone bursts at their best frequencies (BFs). Our results show that systematic relationships exist between the receptive-field properties and discharge patterns of cochlear nucleus units. Type I units give only excitatory responses to tones and noise. They are characterized by primary-like and chopper discharge patterns. Some units in the anteroventral cochlear nucleus have prepotentials in their spike waveforms. Prepotential units most often show primary-like discharge patterns, but prepotential units characterized by nonprimary-like discharge patterns are also found. Most prepotential units lack detectable inhibitory sidebands (type I), but two of the nonprimary-like prepotential units encountered in this study had inhibitory sidebands (type III). Type III units also give excitatory responses to BF tones, but they have inhibitory sidebands. Most type III units give chopper discharge patterns, and these units can be recorded throughout the cochlear nucleus. Some type III units in the dorsal cochlear nucleus give complex discharge patterns that can be described as a composite of the pauser pattern and other patterns. The complexity of these responses seems to increase as the amount of inhibition at BF increases. Type I/III units give excitatory responses to tones and noise, but have little or no spontaneous activity so they cannot be tested directly for inhibitory responses. Type I/III units typically show chopper discharge patterns. One group of type I/III units have rate-level functions with sloping saturation, suggesting that these may receive a predominance of input from low spontaneous rate auditory nerve fibers. Type II units are nonspontaneous and give excitatory responses to tones, but give weak or no responses to noise. While type II units are homogeneous as a group in terms of their response maps. BF rate-level functions, and responses to noise, they show a variety of discharge patterns in response to short tone bursts at BF.(ABSTRACT TRUNCATED AT 400 WORDS)

The Roles Potassium Currents Play in Regulating the Electrical Activity of Ventral Cochlear Nucleus Neurons

2003 ◽  
Vol 89 (6) ◽  
pp. 3097-3113 ◽  
Author(s):  
Jason S. Rothman ◽  
Paul B. Manis
Keyword(s):  
Cochlear Nucleus ◽  
Auditory Nerve ◽  
Threshold Current ◽  
Repetitive Firing ◽  
Resting Membrane Potential ◽  
Type I ◽  
Type Ii Cells ◽  
Type Ii ◽  
Ventral Cochlear Nucleus ◽  
Discharge Patterns

Using kinetic data from three different K+ currents in acutely isolated neurons, a single electrical compartment representing the soma of a ventral cochlear nucleus (VCN) neuron was created. The K+ currents include a fast transient current ( IA), a slow-inactivating low-threshold current ( ILT), and a noninactivating high-threshold current ( IHT). The model also includes a fast-inactivating Na+ current, a hyperpolarization-activated cation current ( Ih), and 1–50 auditory nerve synapses. With this model, the role IA, ILT, and IHT play in shaping the discharge patterns of VCN cells is explored. Simulation results indicate that IHT mainly functions to repolarize the membrane during an action potential, and IA functions to modulate the rate of repetitive firing. ILT is found to be responsible for the phasic discharge pattern observed in Type II cells (bushy cells). However, by adjusting the strength of ILT, both phasic and regular discharge patterns are observed, demonstrating that a critical level of ILT is necessary to produce the Type II response. Simulated Type II cells have a significantly faster membrane time constant in comparison to Type I cells (stellate cells) and are therefore better suited to preserve temporal information in their auditory nerve inputs by acting as precise coincidence detectors and having a short refractory period. Finally, we demonstrate that modulation of Ih, which changes the resting membrane potential, is a more effective means of modulating the activation level of ILT than simply modulating ILT itself. This result may explain why ILT and Ih are often coexpressed throughout the nervous system.

Response properties of units in the dorsal cochlear nucleus of unanesthetized decerebrate gerbil

1996 ◽  
Vol 75 (4) ◽  
pp. 1411-1431 ◽  
Author(s):  
K. A. Davis ◽  
J. Ding ◽  
T. E. Benson ◽  
H. F. Voigt
Keyword(s):  
Dorsal Cochlear Nucleus ◽  
Type I ◽  
Type Ii ◽  
Decerebrate Cat ◽  
Excitatory Response ◽  
Type Iii ◽  
Type Iv ◽  
Noise Type ◽  
Rate Versus ◽  
Excitatory Responses

1. The electrophysiological responses of single units in the dorsal cochlear nucleus of unanesthetized decerebrate Mongolian gerbil (Meriones unguiculatus) were recorded. Units were classified according to the response map scheme of Evans and Nelson as modified by Young and Brownell, Young and Voigt, and Shofner and Young. Type II units have a V-shaped excitatory response map similar to typical auditory nerve tuning curves but little or no spontaneous activity (SpAc < 2.5 spikes/s) and little or no response to noise. Type I/III units also have a V-shaped excitatory map and SpAc < 2.5 spikes/s, but have an excitatory response to noise. Type III units have a V-shaped excitatory map with inhibitory sidebands, SpAc > 2.5 spikes/s, and an excitatory response to noise. Type IV-T units typically also have a V-shaped excitatory map with inhibitory sidebands, but have a highly nonmonotonic rate versus level response to best frequency (BF) tones like type IV units, SpAc > 2.5 spikes/s, and an excitatory response to noise. Type IV units have a predominantly inhibitory response map above an island of excitation of BF, SpAc > 2.5 spikes/s, and an excitatory response to noise. We present results for 133 units recorded with glass micropipette electrodes. The purpose of this study was to establish a normative response map data base in this species for ongoing structure/function and correlation studies. 2. The major types of units (type II, type I/III, type III, type IV-T, and type IV) found in decerebrate cat are found in decerebrate gerbil. However, the percentage of type II (7.5%) and type IV (11.3%) units encountered are smaller and the percentage of type III (62.4%) units is larger in decerebrate gerbil than in decerebrate cat. In comparison, Shofner and Young found 18.5% type II units, 30.6% type IV units, and 23.1% type III units using metal electrodes. 3. Two new unit subtypes are described in gerbil: type III-i and type IV-i units. Type III-i units are similar to type III units except that type III-i units are inhibited by low levels of noise and excited by high levels of noise whereas type III units have strictly excitatory responses to noise. Type IV-i units are similar to type IV units except that type IV-i units are excited by low levels of noise and become inhibited by high levels of noise whereas type IV units have strictly excitatory responses to noise. Type III-i units are approximately 30% of the type III population and type IV-i units are approximately 50% of the type IV population. 4. On the basis of the paucity of classic type II units and the reciprocal responses to broadband noise of type III-i and type IV-i units, we postulate that some gerbil type III-i units are the same cell type and have similar synaptic connections as cat type II units. 5. Type II and type I/III units are distinguished from one another on the basis of both their relative noise response, rho, and the normalized slope of the BF tone rate versus level functions beyond the first maximum. Previously, type II units were defined to be those nonspontaneously active units with rho values < 0.3 where rho is defined as the ratio of the maximum noise response minus spontaneous rate to the maximum BF tone response minus spontaneous rate. In the gerbil, the average rho value for type II units is 0.25, although a few values are > 0.3, and the rate-level curves are consistently nonmonotonic with normalized slopes steeper than than -0.007/dB. The average rho value for type I/III units is 0.54, although a few values are < 0.3, and the rate-level curves tend to saturate with slopes shallower than -0.006/dB. In general, the response properties of type II units recorded in gerbil are similar to those recorded in decerebrate cat. 6. In comparison to decerebrate cat, the lower percentage of type IV units recorded in decerebrate gerbil may be due to a species difference (a reduced number of type II units in gerbil) or an electrode bias.

Labelling of non-A, non-B hepatitis infected chimpanzee hepatocytes with nuclease-gold conjugates

1984 ◽  
Vol 42 ◽  
pp. 250-251
Author(s):  
G. D. Gagne ◽  
M. F. Miller ◽  
D. A. Peterson
Keyword(s):  
Endoplasmic Reticulum ◽  
Experimental Infection ◽  
Uranyl Acetate ◽  
Type I ◽  
Cellular Injury ◽  
Type Ii ◽  
Tubular Structures ◽  
Type Iii ◽  
Type Iv ◽  
Infected Chimpanzee

Experimental infection of chimpanzees with non-A, non-B hepatitis (NANB) or with delta agent hepatitis results in the appearance of characteristic cytoplasmic alterations in the hepatocytes. These alterations include spongelike inclusions (Type I), attached convoluted membranes (Type II), tubular structures (Type III), and microtubular aggregates (Type IV) (Fig. 1). Type I, II and III structures are, by association, believed to be derived from endoplasmic reticulum and may be morphogenetically related. Type IV structures are generally observed free in the cytoplasm but sometimes in the vicinity of type III structures. It is not known whether these structures are somehow involved in the replication and/or assembly of the putative NANB virus or whether they are simply nonspecific responses to cellular injury. When treated with uranyl acetate, type I, II and III structures stain intensely as if they might contain nucleic acids. If these structures do correspond to intermediates in the replication of a virus, one might expect them to contain DNA or RNA and the present study was undertaken to explore this possibility.

scholarly journals Perforator preservation technologies (PPT) based on a new neuro-interventional classification in endovascular treatment of perforator involving aneurysms (piANs)

2021 ◽  
Vol 7 (1) ◽  
Author(s):  
Chen Li ◽  
Ao-Fei Liu ◽  
Han-Cheng Qiu ◽  
Xianli Lv ◽  
Ji Zhou ◽  
...  
Keyword(s):  
Endovascular Therapy ◽  
Saccular Aneurysm ◽  
Type I ◽  
Type Ii ◽  
Fusiform Aneurysm ◽  
Type Iii ◽  
Perforating Artery ◽  
Protection Technology ◽  
Perforating Arteries

Abstract Background Treatment of perforator involving aneurysm (piAN) remains a challenge to open and endovascular neurosurgeons. Our aim is to demonstrate a primary outcome of endovascular therapy for piANs with the use of perforator preservation technologies (PPT) based on a new neuro-interventional classification. Methods The piANs were classified into type I: aneurysm really arises from perforating artery, type II: saccular aneurysm involves perforating arteries arising from its neck (IIa) or dome (IIb), and type III: fusiform aneurysm involves perforating artery. Stent protection technology of PPT was applied in type I and III aneurysms, and coil-basket protection technology in type II aneurysms. An immediate outcome of aneurysmal obliteration after treatment was evaluated (satisfactory obliteration: the saccular aneurysm body is densely embolized (I), leaving a gap in the neck (IIa) or dome (IIb) where the perforating artery arising; fusiform aneurysm is repaired and has a smooth inner wall), and successful perforating artery preservation was defined as keeping the good antegrade flow of those perforators on postoperative angiography. The periprocedural complication was closely monitored, and clinical and angiographic follow-ups were performed. Results Six consecutive piANs (2 ruptured and 4 unruptured; 1 type I, 2 type IIa, 2 type IIb, and 1 type III) in 6 patients (aged from 43 to 66 years; 3 males) underwent endovascular therapy between November 2017 and July 2019. The immediate angiography after treatment showed 6 aneurysms obtained satisfactory obliteration, and all of their perforating arteries were successfully preserved. During clinical follow-up of 13–50 months, no ischemic or hemorrhagic event of the brain occurred in the 6 patients, but has one who developed ischemic event in the territory of involving perforators 4 h after operation and completely resolved within 24 h. Follow-up angiography at 3 to 10M showed patency of the parent artery and perforating arteries of treated aneurysms, with no aneurysmal recurrence. Conclusions Our perforator preservation technologies on the basis of the new neuro-interventional classification seem feasible, safe, and effective in protecting involved perforators while occluding aneurysm.

scholarly journals Intracellular and Extracellular Markers of Lethality in Osteogenesis Imperfecta: A Quantitative Proteomic Approach

2021 ◽  
Vol 22 (1) ◽  
pp. 429
Author(s):  
Luca Bini ◽  
Domitille Schvartz ◽  
Chiara Carnemolla ◽  
Roberta Besio ◽  
Nadia Garibaldi ◽  
...  
Keyword(s):  
Osteogenesis Imperfecta ◽  
Type I Collagen ◽  
Type I ◽  
Tandem Mass ◽  
Type Ii ◽  
Type Iii ◽  
Bioinformatic Tools ◽  
Proteomic Approach ◽  
Fibrillin 1 ◽  
Heritable Disorder

Osteogenesis imperfecta (OI) is a heritable disorder that mainly affects the skeleton. The inheritance is mostly autosomal dominant and associated to mutations in one of the two genes, COL1A1 and COL1A2, encoding for the type I collagen α chains. According to more than 1500 described mutation sites and to outcome spanning from very mild cases to perinatal-lethality, OI is characterized by a wide genotype/phenotype heterogeneity. In order to identify common affected molecular-pathways and disease biomarkers in OI probands with different mutations and lethal or surviving phenotypes, primary fibroblasts from dominant OI patients, carrying COL1A1 or COL1A2 defects, were investigated by applying a Tandem Mass Tag labeling-Liquid Chromatography-Tandem Mass Spectrometry (TMT LC-MS/MS) proteomics approach and bioinformatic tools for comparative protein-abundance profiling. While no difference in α1 or α2 abundance was detected among lethal (type II) and not-lethal (type III) OI patients, 17 proteins, with key effects on matrix structure and organization, cell signaling, and cell and tissue development and differentiation, were significantly different between type II and type III OI patients. Among them, some non–collagenous extracellular matrix (ECM) proteins (e.g., decorin and fibrillin-1) and proteins modulating cytoskeleton (e.g., nestin and palladin) directly correlate to the severity of the disease. Their defective presence may define proband-failure in balancing aberrances related to mutant collagen.

scholarly journals Brachial supporting structure of Spiriferida (Brachiopoda)

2020 ◽  
pp. 1-15
Author(s):  
Zhiwei Yuan ◽  
Wen Guo ◽  
Dan Lyu ◽  
Yuanlin Sun
Keyword(s):  
Mantle Cavity ◽  
Family Type ◽  
Type I ◽  
Type Ii ◽  
Feeding Apparatus ◽  
Single Family ◽  
Supporting Structure ◽  
Type Iii ◽  
Type Iv ◽  
Evolutionary Lineages

Abstract The filter-feeding organ of some extinct brachiopods is supported by a skeletal apparatus called the brachidium. Although relatively well studied in Atrypida and Athyridida, the brachidial morphology is usually neglected in Spiriferida. To investigate the variations of brachidial morphology in Spiriferida, 65 species belonging to eight superfamilies were analyzed. Based on the presence/absence of the jugal processes and normal/modified primary lamellae of the spiralia, four types of brachidium are recognized. Type-I (with jugal processes) and Type-II (without jugal processes), both having normal primary lamellae, could give rise to each other by losing/re-evolving the jugal processes. Type-III, without jugal processes, originated from Type-II through evolution of the modified lateral-convex primary lamellae, and it subsequently gave rise to Type-IV by evolving the modified medial-convex primary lamellae. The evolution of brachidia within individual evolutionary lineages must be clarified because two or more types can be present within a single family. Type-III and Type-IV are closely associated with the prolongation of the crura, representing innovative modifications of the feeding apparatus in response to possible shift in the position of the mouth towards the anterior, allowing for more efficient feeding on particles entering the mantle cavity from the anterior gape. Meanwhile, the modified primary lamellae adjusted/regulated the feeding currents. The absence of spires in some taxa with Type-IV brachidium might suggest that they developed a similar lophophore to that in some extant brachiopods, which can extend out of the shell.

scholarly journals Understanding the Evolution and Applications of Intelligent Systems via a Tri-X Intelligence (TI) Model

Processes ◽  
2021 ◽  
Vol 9 (6) ◽  
pp. 1080
Author(s):  
Min Zhao ◽  
Zhenbo Ning ◽  
Baicun Wang ◽  
Chen Peng ◽  
Xingyu Li ◽  
...  
Keyword(s):  
Intelligent Systems ◽  
Intelligent Manufacturing ◽  
Type I ◽  
Type Ii ◽  
Multiple Perspectives ◽  
Ternary Interaction ◽  
Physical Systems ◽  
Type Iii ◽  
Dynamic Level ◽  
Systematic Scheme

The evolution and application of intelligence have been discussed from perspectives of life, control theory and artificial intelligence. However, there has been no consensus on understanding the evolution of intelligence. In this study, we propose a Tri-X Intelligence (TI) model, aimed at providing a comprehensive perspective to understand complex intelligence and the implementation of intelligent systems. In this work, the essence and evolution of intelligent systems (or system intelligentization) are analyzed and discussed from multiple perspectives and at different stages (Type I, Type II and Type III), based on a Tri-X Intelligence model. Elemental intelligence based on scientific effects (e.g., conscious humans, cyber entities and physical objects) is at the primitive level of intelligence (Type I). Integrated intelligence formed by two-element integration (e.g., human-cyber systems and cyber-physical systems) is at the normal level of intelligence (Type II). Complex intelligence formed by ternary-interaction (e.g., a human-cyber-physical system) is at the dynamic level of intelligence (Type III). Representative cases are analyzed to deepen the understanding of intelligent systems and their future implementation, such as in intelligent manufacturing. This work provides a systematic scheme, and technical supports, to understand and develop intelligent systems.

Morphological types of spermatheca in Coreidae: bearing on intra-familial classification and tribal-groupings (Hemiptera: Heteroptera)

Zootaxa ◽  
2020 ◽  
Vol 4834 (4) ◽  
pp. 451-501
Author(s):  
DOMINIQUE PLUOT-SIGWALT ◽  
PIERRE MOULET
Keyword(s):  
Western Hemisphere ◽  
Type I ◽  
Type Ii ◽  
Type Iii ◽  
Spermathecal Duct ◽  
Eastern Hemisphere ◽  
Intermediate Part ◽  
Muscular Pump ◽  
Familial Classification

The morphology of the spermatheca is described in 109 species of 86 genera representing all four currently recognised subfamilies of Coreidae, covering the undivided Hydarinae, both tribes of Pseudophloeinae, all three tribes of Meropachyinae and 27 of the 32 tribes of Coreinae. Three types of spermatheca are recognised. Type I is bipartite, consisting only of a simple tube differentiated into distal seminal receptacle and proximal spermathecal duct and lacks the intermediate part present in most Pentatomomorpha, in which it serves as muscular pump. Type II is also bipartite but more elaborate in form with the receptacle generally distinctly wider than the duct. Type III is tripartite, with receptacle, duct and an often complex intermediate part. Four subtypes are recognised within type III. Type I is found only in Hydarinae and type II only in Pseudophloeinae. Type III is found in both Coreinae and Meropachyinae. Subtype IIIA (“Coreus-group”) unites many tribes from the Eastern Hemisphere and only one (Spartocerini) from the Western Hemisphere. Subtypes IIIB (“Nematopus-group”) and IIID (“Anisoscelis-group”) are confined to taxa from the Western Hemisphere and subtype IIIC (“Chariesterus-group”) is found in tribes from both hemispheres. The polarity of several characters of the intermediate part and some of the spermathecal duct is evaluated, suggesting autapomorphies or apomorphies potentially relevant to the classification of Coreidae at the sufamilial and tribal levels. Characters of the intermediate part strongly indicate that the separation of Meropachyinae and Coreinae as currently constituted cannot be substantiated. The tribes Anisoscelini, Colpurini, Daladerini and Hyselonotini are heterogeneous, each exhibiting two subtypes of spermatheca, and probably polyphyletic. Two tribes, Cloresmini and Colpurini, requiring further investigation remain unplaced. This study demonstrates the great importance of characters of the spermatheca, in particular its intermediate part, for research into the phylogeny and taxonomy of Pentatomomorpha. 

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