Wallenberg's lateral medullary syndrome with loss of pain and temperature sensation on the contralateral face: clinical, MRI and electrophysiological studies

1993 ◽  
Vol 240 (8) ◽  
pp. 462-467 ◽  
Author(s):  
Lie-Gan Chia ◽  
Wu-Chung Shen
Keyword(s):  
Temperature Sensation ◽  
Lateral Medullary Syndrome ◽  
Electrophysiological Studies ◽  
Clinical Mri

The Involuntary Capture of Attention by Sound

2010 ◽  
Vol 57 (1) ◽  
pp. 68-76 ◽  
Author(s):  
Fabrice B. R. Parmentier ◽  
Pilar Andrés
Keyword(s):  
Older Adults ◽  
Mismatch Negativity ◽  
Visual Task ◽  
The Novel ◽  
Auditory Oddball ◽  
Current Trial ◽  
Electrophysiological Responses ◽  
Electrophysiological Studies ◽  
The Cross ◽  
Task Sets

The presentation of auditory oddball stimuli (novels) among otherwise repeated sounds (standards) triggers a well-identified chain of electrophysiological responses: The detection of acoustic change (mismatch negativity), the involuntary orientation of attention to (P3a) and its reorientation from the novel. Behaviorally, novels reduce performance in an unrelated visual task (novelty distraction). Past studies of the cross-modal capture of attention by acoustic novelty have typically discarded from their analysis the data from the standard trials immediately following a novel, despite some evidence in mono-modal oddball tasks of distraction extending beyond the presentation of deviants/novels (postnovelty distraction). The present study measured novelty and postnovelty distraction and examined the hypothesis that both types of distraction may be underpinned by common frontally-related processes by comparing young and older adults. Our data establish that novels delayed responses not only on the current trial and but also on the subsequent standard trial. Both of these effects increased with age. We argue that both types of distraction relate to the reconfiguration of task-sets and discuss this contention in relation to recent electrophysiological studies.

Lateral medullary syndrome

2015 ◽  
Vol 4 (2) ◽  
pp. 188
Author(s):  
NV Sundarachary ◽  
A Sridhar
Keyword(s):  
Lateral Medullary Syndrome

The Neurobiology of Reading Differs for Deaf and Hearing Adults

2020 ◽  
pp. 346-359
Author(s):  
Karen Emmorey
Keyword(s):  
Semantic Processing ◽  
Event Related Potentials ◽  
Coarse Grained ◽  
Reading Success ◽  
Deaf Readers ◽  
Electrophysiological Studies ◽  
Deaf Adults ◽  
Related Potentials ◽  
Reading System ◽  
New Evidence

Recent neuroimaging and electrophysiological studies reveal how the reading system successfully adapts when phonological codes are relatively coarse-grained due to reduced auditory input during development. New evidence suggests that the optimal end-state for the reading system may differ for deaf versus hearing adults and indicates that certain neural patterns that are maladaptive for hearing readers may be beneficial for deaf readers. This chapter focuses on deaf adults who are signers and have achieved reading success. Although the left-hemisphere-dominant reading circuit is largely similar in both deaf and hearing individuals, skilled deaf readers exhibit a more bilateral neural response to written words and sentences than their hearing peers, as measured by event-related potentials and functional magnetic resonance imaging. Skilled deaf readers may also rely more on neural regions involved in semantic processing than hearing readers do. Overall, emerging evidence indicates that the neural markers for reading skill may differ for deaf and hearing adults.

scholarly journals Canine Myocytes Represent a Good Model for Human Ventricular Cells Regarding Their Electrophysiological Properties

2021 ◽  
Vol 14 (8) ◽  
pp. 748
Author(s):  
Péter P. Nánási ◽  
Balázs Horváth ◽  
Fábián Tar ◽  
János Almássy ◽  
Norbert Szentandrássy ◽  
...  
Keyword(s):  
Action Potential ◽  
Time Course ◽  
Laboratory Animals ◽  
Delayed Rectifier ◽  
Ion Currents ◽  
Human Cardiomyocytes ◽  
Ventricular Cells ◽  
Repolarization Reserve ◽  
Electrophysiological Studies ◽  
K Current

Due to the limited availability of healthy human ventricular tissues, the most suitable animal model has to be applied for electrophysiological and pharmacological studies. This can be best identified by studying the properties of ion currents shaping the action potential in the frequently used laboratory animals, such as dogs, rabbits, guinea pigs, or rats, and comparing them to those of human cardiomyocytes. The authors of this article with the experience of three decades of electrophysiological studies, performed in mammalian and human ventricular tissues and isolated cardiomyocytes, summarize their results obtained regarding the major canine and human cardiac ion currents. Accordingly, L-type Ca2+ current (ICa), late Na+ current (INa-late), rapid and slow components of the delayed rectifier K+ current (IKr and IKs, respectively), inward rectifier K+ current (IK1), transient outward K+ current (Ito1), and Na+/Ca2+ exchange current (INCX) were characterized and compared. Importantly, many of these measurements were performed using the action potential voltage clamp technique allowing for visualization of the actual current profiles flowing during the ventricular action potential. Densities and shapes of these ion currents, as well as the action potential configuration, were similar in human and canine ventricular cells, except for the density of IK1 and the recovery kinetics of Ito. IK1 displayed a largely four-fold larger density in canine than human myocytes, and Ito recovery from inactivation displayed a somewhat different time course in the two species. On the basis of these results, it is concluded that canine ventricular cells represent a reasonably good model for human myocytes for electrophysiological studies, however, it must be borne in mind that due to their stronger IK1, the repolarization reserve is more pronounced in canine cells, and moderate differences in the frequency-dependent repolarization patterns can also be anticipated.

scholarly journals Morphological Characterization of the Antennal Sensilla of the Afrotropical Sand Fly, Phlebotomus duboscqi (Diptera: Psychodidae)

2020 ◽  
Author(s):  
Ana Cristina Bahia ◽  
Ana Beatriz F Barletta ◽  
Luciana Conceição Pinto ◽  
Alessandra S Orfanó ◽  
Rafael Nacif-Pimenta ◽  
...  
Keyword(s):  
Morphological Characters ◽  
Morphological Characterization ◽  
Sand Fly ◽  
Antennal Sensilla ◽  
Olfactory Sensilla ◽  
Zoonotic Cutaneous Leishmaniasis ◽  
Electrophysiological Studies ◽  
Phlebotomus Duboscqi ◽  
Well Differentiated ◽  
Function Number

Abstract We investigated by scanning electron microscopy the morphology, distribution, and abundance of antennal sensilla of females Phlebotomus duboscqi sand fly, an important vector of zoonotic cutaneous leishmaniasis at Afrotropical region. Thirteen well-differentiated sensilla were identified, among six types of cuticular sensilla. The probable function of these sensillary types is discussed in relation to their external structure and distribution. Five sensillary types were classified as olfactory sensilla, as they have specific morphological characters of sensilla with this function. Number and distribution of sensilla significantly differed between antennal segments. The results of the present work, besides corroborating in the expansion of the morphological and ultrastructural knowledge of P. duboscqi, can foment future electrophysiological studies for the development of volatile semiochemicals, to be used as attractants in traps for monitoring and selective vector control of this sand fly.

scholarly journals Defining the Role of Attention in Hierarchical Auditory Processing

2021 ◽  
Vol 11 (1) ◽  
pp. 112-128
Author(s):  
Caitlin N. Price ◽  
Deborah Moncrieff
Keyword(s):  
Auditory Processing ◽  
Auditory Pathway ◽  
Simultaneous Recording ◽  
Neural Encoding ◽  
Top Down ◽  
Attentional Processes ◽  
Clinical Interventions ◽  
Speech In Noise ◽  
Behavioral Studies ◽  
Electrophysiological Studies

Communication in noise is a complex process requiring efficient neural encoding throughout the entire auditory pathway as well as contributions from higher-order cognitive processes (i.e., attention) to extract speech cues for perception. Thus, identifying effective clinical interventions for individuals with speech-in-noise deficits relies on the disentanglement of bottom-up (sensory) and top-down (cognitive) factors to appropriately determine the area of deficit; yet, how attention may interact with early encoding of sensory inputs remains unclear. For decades, attentional theorists have attempted to address this question with cleverly designed behavioral studies, but the neural processes and interactions underlying attention’s role in speech perception remain unresolved. While anatomical and electrophysiological studies have investigated the neurological structures contributing to attentional processes and revealed relevant brain–behavior relationships, recent electrophysiological techniques (i.e., simultaneous recording of brainstem and cortical responses) may provide novel insight regarding the relationship between early sensory processing and top-down attentional influences. In this article, we review relevant theories that guide our present understanding of attentional processes, discuss current electrophysiological evidence of attentional involvement in auditory processing across subcortical and cortical levels, and propose areas for future study that will inform the development of more targeted and effective clinical interventions for individuals with speech-in-noise deficits.

scholarly journals Comprehensive phenotyping revealed transient startle response reduction and histopathological gadolinium localization to perineuronal nets after gadodiamide administration in rats

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Johanna Habermeyer ◽  
Janina Boyken ◽  
Julia Harrer ◽  
Fabio Canneva ◽  
Veronika Ratz ◽  
...  
Keyword(s):  
Neuronal Cell ◽  
Cell Loss ◽  
Repeated Administration ◽  
Perineuronal Net ◽  
Treatment Groups ◽  
Long Time ◽  
Clinical Consequences ◽  
Molecular Weight Fractions ◽  
Clinical Mri ◽  
Pathway Deregulation

AbstractGadolinium based contrast agents (GBCAs) are widely used in clinical MRI since the mid-1980s. Recently, concerns have been raised that trace amounts of Gadolinium (Gd), detected in brains even long time after GBCA application, may cause yet unrecognized clinical consequences. We therefore assessed the behavioral phenotype, neuro-histopathology, and Gd localization after repeated administration of linear (gadodiamide) or macrocyclic (gadobutrol) GBCA in rats. While most behavioral tests revealed no difference between treatment groups, we observed a transient and reversible decrease of the startle reflex after gadodiamide application. Residual Gd in the lateral cerebellar nucleus was neither associated with a general gene expression pathway deregulation nor with neuronal cell loss, but in gadodiamide-treated rats Gd was associated with the perineuronal net protein aggrecan and segregated to high molecular weight fractions. Our behavioral finding together with Gd distribution and speciation support a substance class difference for Gd presence in the brain after GBCA application.

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