Thèses sur le sujet « Rat Barrel Cortex Dynamics »
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Beeren, L. K. « Probing network dynamics in barrel cortex ». Thesis, University College London (University of London), 2012. http://discovery.ucl.ac.uk/1348307/.
Texte intégralLehohla, Molupe. « A study of glutamate receptor function in the rat barrel cortex ». Master's thesis, University of Cape Town, 2001. http://hdl.handle.net/11427/3261.
Texte intégralSalazar, Eduardo 1962. « GABAᴀ Receptors in Rat Whisker Barrel Cortex : Effects of Sensory Deprivation ». Thesis, University of North Texas, 1995. https://digital.library.unt.edu/ark:/67531/metadc279232/.
Texte intégralDoron, Guy. « Psychophysical characterization of single neuron stimulation effects in rat barrel cortex ». Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2013. http://dx.doi.org/10.18452/16757.
Texte intégralThe action potential (AP) activity of single cortical neurons can evoke measurable sensory effects, but it is not known how spiking parameters and specific neuronal subtypes affect the evoked sensations. Here we applied a reverse physiology approach to investigate the relationship between single neuron activity and sensation. First, we provide a detailed description of the procedures involved in nanostimulation, a single-cell stimulation method derived from the juxtacellular labeling technique. Nanostimulation is easy to apply and can be directed to a wide variety of identifiable neurons in anesthetized and awake animals. We describe the recording approach and the parameters of the electric configuration underlying nanostimulation. While exact AP timing has not been achieved, AP frequency and AP number can be parametrically controlled. We demonstrate that nanostimulation can also be used to selectively inhibit sensory responses in identifiable neurons. Next, we examined the effects of AP frequency, AP number and spike train regularity on the detectability of single-cell stimulation in rat somatosensory cortex. For putative excitatory, regular spiking neurons detectability increased with decreasing AP frequencies and decreasing AP numbers. Stimulation of single putative inhibitory, fast spiking neurons led to much larger sensory effects that were not dependent on AP frequency and AP number. In addition, we found that spike train irregularity greatly increased the sensory effects of putative excitatory neurons, with irregular spike trains being detected in on average 8% of trials. Our data suggest that the behaving animal is extremely sensitive to cortical APs and their temporal patterning.
Tanaka, Yasuhiro. « Local connections of excitatory neurons to corticothalamic neurons in the rat barrel cortex ». Kyoto University, 2012. http://hdl.handle.net/2433/157432.
Texte intégralBobrov, Evgeny. « Rat social touch ». Doctoral thesis, Humboldt-Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2014. http://dx.doi.org/10.18452/17036.
Texte intégralRats use their stiff facial hairs (whiskers) for somatosensation, and the pathway from the whiskers to the primary somatosensory cortex (barrel cortex, BC) is well known. Rats also show diverse social behaviors, including touch of conspecifics with their whiskers. The representation of these social touch signals in the brain is however unknown. Thus, the present study aimed at characterizing the neuronal representation of social touch signals in BC and comparing them with non-social somatosensory stimulation. Using extracellular single-cell recordings in freely-moving rats, I could show that the activity of a large fraction of BC neurons is modulated by social touch. Responses were typically excitatory and the pattern of firing rates during interactions differed between cortical layers. Rats preferred interactions with alive conspecifics over inanimate stimuli. Whisking strategies also differed in that inanimate stimuli were whisked at with more regular movements from more protracted set angles. Neuronal responses were also different, such that objects elicited slightly but consistently weaker responses than alive rats. Interestingly, I observed sex-specific differences in neuronal responses. Prominently, there was stronger modulation by social touch in regular-spikers (RS) recorded from males. This could not be explained by behavioral measures, possibly indicating a neural origin of this difference. Further, RS from females fired much more weakly when females were in estrus. In summary, this is the first study that investigated social signals in a primary sensory area of freely-moving animals at the cellular level. It suggests that representations in sensory cortices might be less stimulus-driven and more top-down modulated than previously thought.
Davies, Lucy Anne. « Encoding strategies and mechanisms underpinning adaptation to stimulus statistics in the rat barrel cortex ». Thesis, University of Plymouth, 2011. http://hdl.handle.net/10026.1/559.
Texte intégralEstebanez, Luc. « Caractérisation des traitements sensoriels dans le cortex à tonneaux du rat anesthésié ». Phd thesis, Ecole Normale Supérieure de Paris - ENS Paris, 2011. http://tel.archives-ouvertes.fr/tel-00696553.
Texte intégralHaack, Gina [Verfasser]. « Synaptic structure, physiology and morphology of layer 4 excitatory neurons in rat barrel cortex / Gina Haack ». Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2011. http://d-nb.info/1018202870/34.
Texte intégralBender, Kevin James. « Mechanisms of deprivation-induced map plasticity at layer 4 to layer 2/3 synapses in rat barrel cortex / ». Diss., Connected to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2005. http://wwwlib.umi.com/cr/ucsd/fullcit?p3187822.
Texte intégralTitle from first page of PDF file (viewed January 11, 2006). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references.
Kesterson, Kay Lee. « Effects of Elevated Serotonin Levels on Patterns of GAP-43 Expression During Barrel Development in Rat Somatosensory Cortex ». University of Toledo Health Science Campus / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=mco1130268171.
Texte intégralDoron, Guy [Verfasser], Michael [Akademischer Betreuer] Brecht, Benjamin [Akademischer Betreuer] Lindner et Matthew [Akademischer Betreuer] Larkum. « Psychophysical characterization of single neuron stimulation effects in rat barrel cortex / Guy Doron. Gutachter : Michael Brecht ; Benjamin Lindner ; Matthew Larkum ». Berlin : Humboldt Universität zu Berlin, Mathematisch-Naturwissenschaftliche Fakultät I, 2013. http://d-nb.info/1036680320/34.
Texte intégralMolina, Leonardo A. « Alteration of neural dynamics in the rat medial prefrontal cortex by an NMDA antagonist ». Thesis, Lethbridge, Alta. : University of Lethbridge, Dept. of Neuroscience, c2012, 2012. http://hdl.handle.net/10133/3264.
Texte intégralxi, 42 leaves : ill. ; 29 cm
Yang, Danqing [Verfasser], Dirk [Akademischer Betreuer] Feldmeyer et Björn Michael [Akademischer Betreuer] Kampa. « Characterization of synaptic connections and cholinergic modulation of layer 6A microcircuitry in rat barrel cortex / Danqing Yang ; Dirk Feldmeyer, Björn Michael Kampa ». Aachen : Universitätsbibliothek der RWTH Aachen, 2018. http://d-nb.info/1187346438/34.
Texte intégralQi, Guanxiao [Verfasser]. « Intra- and interlaminar excitatory synaptic connections of layer 4 spiny neurons and layer 6A pyramidal cells in rat barrel cortex / Guanxiao Qi ». Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2011. http://d-nb.info/1014298148/34.
Texte intégralSivarajan, Vishalini [Verfasser], Dirk [Akademischer Betreuer] Feldmeyer et Björn M. [Akademischer Betreuer] Kampa. « Morphological and functional characterisation of non-fast spiking interneurons in layer 4 microcircuitry of rat barrel cortex / Vishalini Sivarajan ; Dirk Feldmeyer, Björn M. Kampa ». Aachen : Universitätsbibliothek der RWTH Aachen, 2017. http://d-nb.info/1158667817/34.
Texte intégralCecchetto, Claudia. « Neuronal Population Encoding of Sensory Information in the Rat Barrel Cortex : Local Field Potential Recording and Characterization by an Innovative High-Resolution Brain-Chip Interface ». Doctoral thesis, Università degli studi di Padova, 2016. http://hdl.handle.net/11577/3424482.
Texte intégralLe reti neuronali sono alla base della codifica dell'informazione cerebrale. L'obiettivo principale dello studio delle popolazioni neuronali è quello di caratterizzare la relazione tra uno stimolo e la risposta individuale o globale dei neuroni e di studiare il rapporto tra le varie attività elettriche dei neuroni appartenenti ad una particolare rete, comprendendo anche come la topologia e la connettività della rete neuronale influiscano sulla loro funzionalità. Fino ad oggi, molte tecniche sono state sviluppate per studiare questi sistemi complessi: studi a singola cellula mirano a studiare singoli neuroni e le loro connessioni con un numero limitato di altre cellule; sul lato opposto, approcci su larga scala e a bassa risoluzione, come la risonanza magnetica funzionale o l'elettroencefalogramma, registrano segnali elettrofisiologici generati nel cervello da vaste popolazioni di cellule. Più recentemente, sono state sviluppate tecniche di registrazione multisito che mirano ad abbattere le limitazioni dei precedenti approcci, rendendo possibile la misurazione ad alta risoluzione di segnali generati da grandi ensamble neuronali e da diverse regioni del cervello simultaneamente, ad esempio mediante l'uso di chip impiantabili a semiconduttore. I potenziali di campo locali (LFP) catturano processi sinaptici chiave che non possono essere estratti dall'attività di spiking di qualche neurone isolato. Numerosi studi hanno utilizzato gli LFP per studiare i meccanismi corticali coinvolti nei processi sensoriali, motori e cognitivi, come la memoria e la percezione. Gli LFP rappresentano anche dei segnali interessanti nell'ambito delle applicazioni neuroprotesiche e per monitorare l'attività cerebrale negli esseri umani, dal momento che possono essere registrati più stabilmente e facilmente in impianti cronici rispetto agli spike neuronali. In questo studio, sono riportati dei profili LFP registrati dalla barrel cortex di ratto tramite chip ad ago ad alta risoluzione basati su tecnologia CMOS e confrontati con quelli ottenuti tramite elettrodi convenzionali in Ag/AgCl inseriti in micropipette di vetro, strumenti comunemente usati in elettrofisiologia. La barrel cortex di ratto è un esempio ben noto di mapping topografico, nel quale ogni baffo sul muso dell'animale è mappato in una specifica area corticale, chiamata barrel. La barrel cortex contiene la rappresentazione sensoriale dei baffi dell'animale e rappresenta uno dei primi stadi di elaborazione dell'informazione tattile, insieme al ganglio del trigemino e al talamo. Essa è un'area di primaria importanza per lo studio del funzionamento della corteccia cerebrale, visto che le colonne corticali che formano i blocchi di base della neocorteccia possono essere visualizzati facilmente all'interno della barrel cortex. La barrel cortex inoltre è utilizzata come sistema di test in numerose metodologie innovative, grazie alla sua struttura unica ed istantaneamente identificabile, e grazie anche al fatto che le specie dotate di barrel, i roditori, sono gli animali da laboratorio più comuni. La barrel cortex e le sue interconnessioni neuronali sono stati oggetto delle ricerche più disparate in questi ultimi decenni. Attualmente, alcuni studi (come questo) non mirano solamente a comprendere meglio la barrel cortex, ma anche ad analizzare problematiche in campi scientifici collegati, utilizzando la barrel cortex come modello base. In questo lavoro, sono stati evocati segnali LFP nella barrel cortex tramite deflessioni ripetute dei baffi dell'animale, realizzate in modo controllato tramite un sistema di deflessione piezoelettrica a closed-loop innescato da un sistema di acquisizione LabView. Le risposte evocate generate nella barrel dalla stimolazione ripetuta dei baffi presentano elevata variabilità nella forma e nelle latenze temporali. Inoltre, il tipo di anestesia utilizzata può influenzare profondamente il profilo della risposta evocata. Questo studio riporta i risultati preliminari sulla variabilità della risposta neuronale e sull'effetto di due anestetici di uso comune su questi segnali, confrontando le distribuzioni delle risposte evocate in ratti anestetizzati con tiletamina-xylazina (il quale agisce prevalentemente sui recettori eccitatori di tipo NMDA) e uretano (che agisce in modo più bilanciato e complesso su entrambi i sistemi eccitatori ed inibitori, preservando la plasticità sinaptica). Sono state analizzate e discusse alcune caratteristiche rappresentative del segnale evocato (ad esempio, le latenze temporali e l'ampiezza degli eventi), registrato a varie profondità corticali. Per tutte le prondità corticali acquisite, sono state stimate le distribuzioni statistiche di tali parametri, in modo da valutare la variabilità degli LFP evocati dalle stimolazioni meccaniche individuali delle vibrisse del ratto lungo l'intera colonna corticale. I primi risultati presentano una grande variabilità nelle risposte corticali, sia in latenza che in ampiezza. Inoltre, è stata riscontrata una differenza significativa nella latenza del primo picco principale delle risposte evocate: gli LFP evocati in animali anestetizzati con tiletamina-xylazina presentavano una latenza più lunga di quelli registrati in ratti anestetizzati con uretano. Inoltre, le distribuzioni dei parametri analizzati erano più strette e piccate in uretano, in corrispondenza di tutte le profondità corticali. Questo comportamento è sicuramente da attribuire al differente meccanismo d'azione dei due anestetici su specifici recettori sinaptici, e quindi nell'elaborazione e nella trasmissione dell'informazione sensoriale lungo tutto il percorso corticale. E' stato inoltre discusso il ruolo della attività basale nella modulazione della risposta evocata. A questo proposito, è stata registrata l'attività spontanea in corrispondenza dei vari layer corticali ed analizzata nel contesto statistico delle 'valanghe neuronali'. Una valanga neuronale è una cascata di attività elettrica in una rete neuronale, la cui distribuzione statistica dei parametri principali (dimensione e vita media) può essere approssimata da una legge di potenza. La distribuzione delle dimensioni di una valanga in una rete neuronale segue una legge di potenza del tipo P(s)=s^-a, con a=1.5. Tale esponente è un riflesso delle correlazioni spaziali a lungo raggio nell'attività neuronale spontanea. Dal momento che i picchi negativi (nLFPs) nelle tracce elettrofisiologiche originano dalla somma di potenziali d'azione sincronizzati generati da neuroni posti nelle vicinanze dell'elettrodo di registrazione, ci siamo chiesti se fosse possibile modellizare i singoli nLFP registrati nell'attività basale tramite un singolo elettrodo come il risultato di valanghe neuronali locali. Pertanto, abbiamo analizzato la distribuzione della dimensione (cioè l'ampiezza in uV) di tali picchi, in modo da identificare una distribuzione power-law appropriata, che potesse descrivere anche le registrazioni a singolo elettrodo. Infine, sono presentate e discusse le prime registrazioni in assoluto degli LFP evocati lungo un'intera colonna corticale ottenute tramite l'ultima generazione di chip impiantabili a tecnologia CMOS. Questi ultimi presentano una matrice di 256 siti di registrazione, organizzata secondo due possibili topologie, 16 x 16 o 4 x 64, e avente una distanza tra gli elettrodi pari a 15 um o 33 um rispettivamente. Una precisa dinamica di propagazione dei potenziali evocati può già essere riconosciuta in questi primissimi profili corticali. Nel prossimo futuro, l'uso di questi dispositivi a semiconduttore potrà aiutare a comprendere il decorso di sindromi neurodegerative come il Parkinson o l'Alzheimer, associando sintomi e comportamenti tipo della malattia a specifiche caratteristiche neuronali. I chip impiantabili potranno anche essere utilizzati come 'electroceuticals', ossia potranno aiutare a rallentare (o addirittura a capovolgere) il decorso delle malattie neurogenerative, costituendo le basi di protesi neuronali in grado di sostenere fisicamente o allenare funzionalmente le popolazioni neuronali danneggiate. L'identificazione e il rilevamento di segnali neuronali ad alta risoluzione aiuterà anche a sviluppare complesse interfacce cervello-macchina, che consentiranno il controllo di protesi intelligenti e che forniranno sofisticati meccanismi di feedback a chi ha perso l'uso di alcune parti del proprio corpo o determinate funzioni cerebrali.
Marx, Manuel [Verfasser]. « Intralaminar and translaminar microcircuits involving excitatory and inhibitory neurons in layer 6B of the somatosensory rat barrel cortex : a morphological, physiological and immunofluorescence study / Manuel Marx ». Aachen : Hochschulbibliothek der Rheinisch-Westfälischen Technischen Hochschule Aachen, 2014. http://d-nb.info/1051528771/34.
Texte intégralWilliams, Mark. « Dynamique de l’excitabilité corticale dans l’épilepsie-absence et intégration sensorielle Integrative properties and transfer function of cortical neurons initiating absence seizures in a rat genetic model Building Up Absence Seizures in the Somatosensory Cortex : From Network to Cellular Epileptogenic Processes ». Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS608.
Texte intégralAn epileptic seizure results from the sudden occurrence of abnormally intense, rhythmic and synchronous neuronal activity, in a more or less broad region of the central nervous system. The clinical consequences are extremely varied, depending on the affected brain areas and the duration of the seizures, ranging from brief localized muscular twitches to a complete loss of consciousness, potentially associated with convulsions. Absence epilepsy is a generalised epilepsy of genetic origin, mostly affecting children of school age. During absence attacks, children experience a suspension of conscious processes in all their dimensions, including an interruption of conscious perceptions. These symptoms are correlated with bilateral spike-wave discharges (SWD) in the electroencephalograms (EEGs). The pathophysiological mechanisms underlying the alteration of consciousness during absences remain the subject of an intense debate, opposing functional dysfunctions on large scale neural networks to a filtering of sensory information by epileptic oscillations. During my PhD research, I explored the alternative, but not exclusive, hypothesis of a dynamic dysfunction in sensory integration processes within primary thalamo-cortical circuits. Given that multi-scale electrophysiological investigations cannot be conducted in epileptic children, I used a genetic model prsenting a strong homology with the human pathology: the Genetic Absence Epilepsy Rat from Strasbourg (GAERS).By combining in vivo electrocorticographic (ECoG) and intracellular recordings in the primary somatosensory cortex (S1), previously identified as the site of seizure initiation, I first analysed the integrative properties and excitability of S1 pyramidal neurons, during and in between seizures, and compared them to those measured in homologous neurons from non-epileptic rats. I showed that these neurons exhibit a higher excitability during inter-ictal periods, expressed as an increased firing response to excitatory stimuli of increasing intensity, as well as an exacerbated tendency to depolarize following a hyperpolarization of large amplitude, suggesting an augmented cationic current h. During seizures, the same neurons showed specific changes in their membrane excitability, according to the spike or wave component in the corresponding ECoG. The spike component was associated with increased current-evoked firing and a decreased membrane resistance. Conversely, the wave was correlated with an increase in membrane resistance and a decrease in excitability. These dynamic changes in neuronal integrative properties suggest an instability of cortical responses during the spike-wave epileptic cycle that could "scramble" sensory signals during seizures. I tested this hypothesis by analysing the sensory responses of cortical neurons, and corresponding thalamo-cortical neurons, to stimulations applied to contralateral whiskers. Although synaptic responses induced in S1 neurons by sensory stimuli were not globally impaired during seizures, they were larger and more likely to trigger action potentials during wave compared to the spike component. This relative increase in neuronal responsiveness during the ECoG wave probably results from the previously described increase in membrane resistance, an augmented driving force of glutamatergic synaptic currents and a higher probability of action potentials discharge in the corresponding thalamic neurons during this component. My doctoral research indicates that sensory inputs processing persists in the thalamo-cortical circuits during SWDs, but that the alternation of the spike and wave components introduces a strong instability of the neuronal responses during seizures. This new pathophysiological mechanism could contribute to the inability to generate a conscious, stable and effective, perception during generalised epileptic seizures
Machado, Lemos Rodrigues Manuel Jürgen [Verfasser], Klaus [Gutachter] Funke et Zoltán F. [Gutachter] Kisvárday. « Modulation of event-related potentials by deviance detection during mismatch negativity-like oddball paradigm in rat barrel cortex / Manuel Jürgen Machado Lemos Rodrigues ; Gutachter : Klaus Funke, Zoltán F. Kisvárday ; Medizinische Fakultät ». Bochum : Ruhr-Universität Bochum, 2017. http://d-nb.info/1150509538/34.
Texte intégralBessieres, Benjamin. « Implication fonctionnelle des récepteurs NMDA corticaux au cours des processus de consolidation systémique et d’oubli de la mémoire associative chez le rat ». Thesis, Bordeaux, 2016. http://www.theses.fr/2016BORD0039/document.
Texte intégralInitially encoded in the hippocampus, new declarative memories are thought to become progressively dependent on a broadly distributed cortical network as they mature and consolidate over time. Although we have a good understanding of the mechanisms underlying the formation of new memories in the hippocampus, little is known about the cellular and molecular mechanisms by which recently acquired information is transformed into remote memories at the cortical level. The N-‐methyl-‐D-‐aspartate receptor (NMDAR) is widely known to be a key player in many aspects of long-‐term experience-‐dependent synaptic changes underlying associative memory processes. Based on their distinct biophysical properties, we postulated that the activity-‐dependent surface dynamics of the two predominant GluN2 subunits (GluN2A and GluN2B) of NMDARs present in the adult neocortex could provide a metaplastic control of synaptic plasticity supporting the progressive embedding and stabilization of long-‐lasting associative memories within cortical networks during memory consolidation. By combining, in adult rats, behavioral, biochemical, pharmacological and innovative strategies consisting in manipulating trafficking of NMDAR subunits at the cell membrane, our results identify a cortical switch in the synaptic GluN2-‐containing NMDAR composition which drives the progressive embedding and stabilization of long-‐lasting memories within cortical networks. We first established that cortical GluN2B-‐containing NMDARs and their specific interactions with the synaptic signaling CaMKII protein are preferentially recruited upon encoding of associative olfactory memories to enable neuronal allocation, the process via which a new memory trace is thought to be allocated to a given neuronal network. As these memories are progressively processed and embedded into cortical networks, we observed a learning-‐induced surface redistribution of cortical GluN2B-‐containing NMDARs outwards or inwards synapses which respectively drives the progressive stabilization and subsequent forgetting of remote memories over time. Finally, increasing the strength, upon encoding, of the initial memory leads to a faster increase of the cortical GluN2A/GluN2B synaptic ratio and accelerates the kinetics of hippocampal-‐cortical interactions, which translated into a faster stabilization of memories within cortical networks. Taken together, our results provide evidence that GluN2B-‐NMDAR surface trafficking controls the fate of remote memories (i.e. stabilization versus forgetting), shedding light on a novel mechanism used by the brain to organize recent and remote memories
Thompson, Garth John. « Neural basis and behavioral effects of dynamic resting state functional magnetic resonance imaging as defined by sliding window correlation and quasi-periodic patterns ». Diss., Georgia Institute of Technology, 2013. http://hdl.handle.net/1853/49083.
Texte intégralNevian, Thomas [Verfasser]. « Calcium dynamics in dendrites and spines of spiny neurons in the somatosensory 'barrel' cortex of the rat / presented by Thomas Nevian ». 2003. http://d-nb.info/966590384/34.
Texte intégralDalefield, Martin. « Temporal Dynamics of Cortical Adaptation ». Master's thesis, 2015. http://hdl.handle.net/1885/112033.
Texte intégralJi, Chin-Yi, et 紀欽益. « Surround Modulation in Different Cortical Layers of Rat Barrel Field Cortex ». Thesis, 2019. http://ndltd.ncl.edu.tw/handle/n37ua9.
Texte intégral國立臺灣大學
心理學研究所
107
The discrete architecture modules of the rat barrel cortex are an important animal model in studying cortical coding of sensory information and its circuitry. Neurons within the same barrel tend to respond mainly to the deflection of a single whisker (called ‘principal whisker’, PW). However, their responses also modulated when surrounding whiskers (SWs) are deflected alone with the PW. When studying the surround modulation effect, most previous studies deflect only the PW and a single SW, a scheme differs significantly from the synchronous movement of multi-whiskers when rats are exploring the environment. In this study, we aimed on the effect of surround modulation by deflecting multi-whiskers simultaneously with different stimulus patterns: a single whisker (single condition), multi-whiskers (n = 5, chosen randomly) moving in the same direction (correlated condition), multi-whiskers (n = 5, chosen randomly) moving in different directions (uncorrelated condition). We tried to address three questions. First, how firing rate and directional tuning were affected by surround modulation in different stimulus patterns (the contextual effect). Second, were the effect of surround modulation different across different cortical layers. Third, in what degree the response in barrel cortex could be characterized by the linear-nonlinear model. Half of the recorded neurons showed significant surround modulation effect. Comparing to the single-whisker condition, neurons in the multi-whisker conditions tended to have lower firing rates and higher directional selectivity indices. Neurons with significant surround suppression were three times as many as those with significant surround facilitation, indicating that surround suppression was dominant in barrel field cortex. The contextual effect in multi-whisker conditions was found only in the supragranular layer – the reduction in firing rate was larger in the correlated condition than in the uncorrelated condition, maybe due to abandon lateral connections among neurons with similar properties. In contrast, the contextual effect was not evident in other two layers. Moreover, cortical responses in barrel field under multi-whisker conditions were less characterized by the LN model than those under single whisker condition. Overall, these results indicated that surround suppression was dominant especially for neurons in the supragranular layer of the barrel field cortex, which might serve an important role in integrating inputs from the granular layer. In contrast, neurons in the granular layer were less affected by surround stimulation and might serve as critical feature detectors (Brecht, 2007).
Zhang, Wanying. « In vivo Dissection of Long Range Inputs to the Rat Barrel Cortex ». Thesis, 2014. https://doi.org/10.7916/D8BV7F7X.
Texte intégralChen, Chi-Sheng, et 陳繼勝. « Functional reorganization between barrel row and barrel arc in rat first somatosensory cortex : A 14C-2-deoxyglucose study ». Thesis, 1997. http://ndltd.ncl.edu.tw/handle/38454619251825737756.
Texte intégralKuo, Kuo-Hsing, et 郭國星. « Direction of functional reorganization in the rat barrel cortex : A 14C-2-Deoxyglucose Study ». Thesis, 1994. http://ndltd.ncl.edu.tw/handle/89244261308305663855.
Texte intégralYang, Jenq-Wei [Verfasser]. « Neural network activity in the neonatal rat barrel cortex in vivo / vorgelegt von Jenq-Wei Yang ». 2011. http://d-nb.info/1012656098/34.
Texte intégralDyhrfjeld-Johnsen, Jonas [Verfasser]. « Investigations of microcircuitry in the rat barrel cortex using an experimentally constrained layer V pyramidal neuron model / vorgelegt von Jonas Dyhrfjeld-Johnsen ». 2004. http://d-nb.info/970132964/34.
Texte intégralAgahari, Fransiscus Adrian. « Serotonergic Modulation of Glutamate Release in Layer II of Rat Somatosensory Cortex : Mechanisms and Network Specificity ». Phd thesis, 2017. http://hdl.handle.net/1885/133300.
Texte intégral