scholarly journals The Medullary Targets of Neurally Conveyed Sensory Information from the Rat Hepatic Portal and Superior Mesenteric Veins

eNeuro ◽  
2021 ◽  
Vol 8 (1) ◽  
pp. ENEURO.0419-20.2021
Author(s):  
Cinthia Garcia-Luna ◽  
Graciela Sanchez-Watts ◽  
Myrtha Arnold ◽  
Guillaume de Lartigue ◽  
Nick DeWalt ◽  
...  
Keyword(s):  
Sensory Information ◽  
Mesenteric Veins ◽  
Hepatic Portal

Convergence of sensory information from abdominal viscera in the rat brain stem

1986 ◽  
Vol 251 (2) ◽  
pp. G169-G175 ◽  
Author(s):  
F. Appia ◽  
W. R. Ewart ◽  
B. S. Pittam ◽  
D. L. Wingate
Keyword(s):  
Portal Vein ◽  
Brain Stem ◽  
Rat Brain ◽  
Sensory Information ◽  
Vagal Afferents ◽  
Gastric Distension ◽  
Significant Difference ◽  
Hepatic Portal Vein ◽  
Hepatic Portal ◽  
Portal Vein Infusion

This study was carried out to establish whether there was convergence of sensory information in the rat brain stem stimulated by physiological activation of gastric mechanoreceptors and hepatic glucoreceptors. Extracellular recordings were made from single neurons in the region of the dorsal vagal nucleus and nucleus of the solitary tract in the medulla. The responses of these neurons to gastric distension, hepatic portal vein perfusion of isotonic D-glucose, and hepatic portal vein infusion of isotonic saline were studied. Fifty-six neurons were studied; it was found that there was no significant difference in the proportion of neurons responding to gastric distension compared with the number responding to either form of hepatic stimulation. In 20 neurons (all 3 types of stimulation were tested on the same neuron), both excitation and inhibition were observed with both forms of visceral stimulation. Of the seven of these neurons that responded to hepatic portal vein infusion, four of them also had an input from gastric mechanoreceptors. Only three of the neurons that responded to hepatic stimulation showed a specific response to hepatic glucose perfusion; in the remainder a component of the response was due to the infusion of the volume itself. The results from these experiments have demonstrated an apparently weak functional synaptic projection carried by hepatic vagal afferents, particularly those responding to changes in portal glucose concentration, which may indicate a rather diffuse and nonspecific sensory system in the liver. These results have also demonstrated the convergence onto neurons in the brain stem of information from gastric and hepatic enteroceptors.(ABSTRACT TRUNCATED AT 250 WORDS)

Relation Between Level of Prefrontal Activity and Subject's Performance

1999 ◽  
Vol 13 (2) ◽  
pp. 117-125 ◽  
Author(s):  
Laurence Casini ◽  
Françoise Macar ◽  
Marie-Hélène Giard
Keyword(s):  
Brain Activity ◽  
Sensory Information ◽  
Practice Phase ◽  
Trained Subjects ◽  
Anagram Task ◽  
Economic Information ◽  
Long Duration ◽  
Level Of Activity ◽  
The Brain ◽  
Processing Mechanism

Abstract The experiment reported here was aimed at determining whether the level of brain activity can be related to performance in trained subjects. Two tasks were compared: a temporal and a linguistic task. An array of four letters appeared on a screen. In the temporal task, subjects had to decide whether the letters remained on the screen for a short or a long duration as learned in a practice phase. In the linguistic task, they had to determine whether the four letters could form a word or not (anagram task). These tasks allowed us to compare the level of brain activity obtained in correct and incorrect responses. The current density measures recorded over prefrontal areas showed a relationship between the performance and the level of activity in the temporal task only. The level of activity obtained with correct responses was lower than that obtained with incorrect responses. This suggests that a good temporal performance could be the result of an efficacious, but economic, information-processing mechanism in the brain. In addition, the absence of this relation in the anagram task results in the question of whether this relation is specific to the processing of sensory information only.

Pulvino-cortical interaction: an integrative role in the control of attention

2019 ◽  
Author(s):  
Alexia Bourgeois ◽  
Carole Guedj ◽  
Emmanuel Carrera ◽  
Patrik Vuilleumier
Keyword(s):  
Executive Control ◽  
Sensory Information ◽  
Relevant Information ◽  
Cortical Circuits ◽  
Attention And Executive Control ◽  
Neural Communication ◽  
Subcortical Regions ◽  
Theoretical Proposal ◽  
Selection Of

Selective attention is a fundamental cognitive function that guides behavior by selecting and prioritizing salient or relevant sensory information of our environment. Despite early evidence and theoretical proposal pointing to an implication of thalamic control in attention, most studies in the past two decades focused on cortical substrates, largely ignoring the contribution of subcortical regions as well as cortico-subcortical interactions. Here, we suggest a key role of the pulvinar in the selection of salient and relevant information via its involvement in priority maps computation. Prioritization may be achieved through a pulvinar- mediated generation of alpha oscillations, which may then modulate neuronal gain in thalamo-cortical circuits. Such mechanism might orchestrate the synchrony of cortico-cortical interaction, by rendering neural communication more effective, precise and selective. We propose that this theoretical framework will support a timely shift from the prevailing cortico- centric view of cognition to a more integrative perspective of thalamic contributions to attention and executive control processes.

الذاكرة الادراكية والسيمانتية لدى طلبة الجامعة

2020 ◽  
pp. 77-93
Author(s):  
أ.م.د عبد العزيز حيدر ◽  
أ.م.د ناجي محمود ناجي ◽  
د.اسراء حسن علي
Keyword(s):  
Sensory Information ◽  
Information Storage ◽  
Term Memory

تعد الذاكرة من العمليات العقلية العليا التي يتم بها تسجيل وحفظ واسترجاع الخبرة الماضية من مدركات وميول وسلوك(Norman, 1980,p1 ) .واذا عرفنا ان السلوك نشاط كلي مركب ديناميكي ، فالذاكرة هي الركيزة الاساسية المميزة لهذا النشاط بابعاده المعرفية و الوجدانية والحركية حيث تعتبر الذاكرة المحور الاساسي لكل العمليات العقلية ،وهي القوة الكامنة وراء كل نشاط نفسي وعقلي اذ بدونها يرى الفرد تكرار الحياة ولايستطيع تعلمها (الازيرجاوي، 1991،ص79).  ان الادراك و التعلم وحل المشكلات ،كل ذلك يستلزم القدرة على تخزين المعلومات، فالادراك يعتمد غالبا على المقارنة بين المعلومات و الماضي و الحاضر، والتعلم يتطلب اكتساب عادات ومعلومات جديدة . ويعتمد حل المشكلات على حفظ سلسلة من الافكار، وكذلك التحدث يتطلب تذكر الكلمات والمعلومات وقليل من قواعد اللغة (دافيدوف، 1976،ص331). ان الوظيفة الرئيسية للذاكرة هي استرجاع الاحداث والمواقف التي سبق ان مرت بخبرة الفرد (الشرقاوي، 1992، ص125) .وعملية التذكر تعتبر من العمليات المعقدة ، حيث انها تتناول عدة عمليات عقلية كالحفظ  retention ، والتعرف recognition، والاستدعاءrecall . وتؤدي الذاكرة دورا هاما في نظام تكوين تناول المعلومات لاعتمادكثير من العمليات العقلية في هذا النظام على عملية التذكر،ويمكن تحديد ثلاث مظاهر اساسية للذاكرة الانسانية: أول هذه المظاهر مايسمى بنظام تخزين المعلومات الحسي  Sensory information Storage وهو على درجة كبيرة من الاهمية بالنسبة لعملية التناول الادراكي للمعلومات الحسية ، والتي عادة لاتستغرق اكثر من اجزاء معدودة من الثانية . اما ثاني هذه المظاهر فهو مايسمى بنظام الذاكرة قصيرة الاجل Short_ term memory حيث تبقى المعلومات لمدة ثوان او ربما لعدة دقائق. ويختلف هذا النظام عن النظام السابق في ان المعلومات تكون قد استغرقت بعد تصنيفها عقب عملية تناولها حسيا وقد يكون الفرد في حاجة ماسة وسريعة الى هذه المعلومات مما يستدعي استرجاعها بشكل فوري ، او انه يقوم باعادة تناولها وتنظيمها للاحتفاظ  بها في الذاكرة مدة اطول .اما ثالث الاجهزة مايسمى بنظام الذاكرة طويلة الاجل Lang_ term memory حيث تبقى التسجيلات الدائمة لخبرات الفرد التي كونها عبر فترات حياته.ويتميز هذا المظهر من الذاكرة بان طاقته ليست محدودة كما في المظهرين السابقين. واهم وظائفه تنظيم المعلومات خلال عملية تخزينها في الذاكرة .والقيام بعملية البحث عن المعلومات المطلوب استرجاعها بعد ذلك حسب مايقتضيه الموقف الذي يكون فيه الفرد(Rabinowitz and Gloter,1985,p80) ان الذاكرة تقوم بوظائف اخرى بعضها يختص باعمال ضبط المعلومات اثناء عملية تناولها سواء اثناء عمل كل نظام من هذه النظم ،او خلال انتقالها عبر هذه النظم . كما تساهم بعض النظم الاخرى في اختيار اجراءات عمل الذاكرة والاشراف على تتابع هذه الاجراءات .

Comparative analysis of intelligent planning methods

2012 ◽  
Vol 9 (2) ◽  
pp. 53-57 ◽  
Author(s):  
O.V. Darintsev ◽  
A.B. Migranov
Keyword(s):  
Neural Networks ◽  
Genetic Algorithms ◽  
Fuzzy Logic ◽  
Comparative Analysis ◽  
Mobile Robots ◽  
Sensory Information ◽  
Working Environment ◽  
Planning Methods ◽  
Intelligent Planning

The main stages of solving the problem of planning movements by mobile robots in a non-stationary working environment based on neural networks, genetic algorithms and fuzzy logic are considered. The features common to the considered intellectual algorithms are singled out and their comparative analysis is carried out. Recommendations are given on the use of this or that method depending on the type of problem being solved and the requirements for the speed of the algorithm, the quality of the trajectory, the availability (volume) of sensory information, etc.

Neuromuscular Control of Movement

2018 ◽  
Keyword(s):  
Nervous System ◽  
Sensory Information ◽  
Neuromuscular Control ◽  
Complex Environments ◽  
Locomotor Rhythm ◽  
Motor Responses ◽  
Reflex Pathways ◽  
Local Reflex ◽  
Local Circuits ◽  
And Control

The control of movement is essential for animals traversing complex environments and operating across a range of speeds and gaits. We consider how animals process sensory information and initiate motor responses, primarily focusing on simple motor responses that involve local reflex pathways of feedback and control, rather than the more complex, longer-term responses that require the broader integration of higher centers within the nervous system. We explore how local circuits facilitate decentralized coordination of locomotor rhythm and examine the fundamentals of sensory receptors located in the muscles, tendons, joints, and at the animal’s body surface. These sensors monitor the animal’s physical environment and the action of its muscles. The sensory information is then carried back to the animal’s nervous system by afferent neurons, providing feedback that is integrated at the level of the spinal cord of vertebrates and sensory-motor ganglia of invertebrates.

Measuring the World

2018 ◽  
Author(s):  
Ann-Sophie Barwich
Keyword(s):  
Sensory Information ◽  
Network Models ◽  
Model System ◽  
Stimulus Input ◽  
Expectancy Effects ◽  
Neural Network Models ◽  
Perceptual Object ◽  
External Objects ◽  
The Common ◽  
The Brain

How much does stimulus input shape perception? The common-sense view is that our perceptions are representations of objects and their features and that the stimulus structures the perceptual object. The problem for this view concerns perceptual biases as responsible for distortions and the subjectivity of perceptual experience. These biases are increasingly studied as constitutive factors of brain processes in recent neuroscience. In neural network models the brain is said to cope with the plethora of sensory information by predicting stimulus regularities on the basis of previous experiences. Drawing on this development, this chapter analyses perceptions as processes. Looking at olfaction as a model system, it argues for the need to abandon a stimulus-centred perspective, where smells are thought of as stable percepts, computationally linked to external objects such as odorous molecules. Perception here is presented as a measure of changing signal ratios in an environment informed by expectancy effects from top-down processes.

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