The Experts below are selected from a list of 324 Experts worldwide ranked by ideXlab platform

G Kobal - One of the best experts on this subject based on the ideXlab platform.

  • sensitivity of the negative mucosal potential to the trigeminal Target Stimulus co2
    Brain Research, 2002
    Co-Authors: Norbert Thurauf, Michael Gunther, E Pauli, G Kobal
    Abstract:

    CO 2 is frequently used in an experimental pain model and in imaging studies investigating the central processing of trigeminal nociceptive information because of its specific trigeminal stimulation properties. The aim of the current study was (1) to investigate the sensitivity of the NMP to small increments of CO 2 Stimulus concentrations (3% CO 2 , v/v) and (2) to characterize the sensory input of CO 2 by determining NMP, detection and pain thresholds and by registering subjective verbal descriptions. Ten subjects participated in the first experimental sessions investigating NMP responses to stimuli of 62, 65, 68% CO 2 (v/v) (Stimulus duration: 1000 ms). Our statistical analysis revealed a dose-dependent increase of the NMP amplitudes and areas under the curves (AUCs) demonstrating the high dynamic resolution of the NMP. Ten subjects participated in the second experimental sessions determining thresholds for NMP, detection and pain (Stimulus duration: 1000 ms). MANOVA analysis revealed significantly different thresholds for detection, NMP and subjective pain judgements (mean and S.D. as percentage CO 2 (v/v): detection: 20.6±9.6, NMP: 42.6±12.5, pain: 50.4±12.0). We could demonstrate the existence of a prepain range below subjective pain thresholds with activation of trigeminal nociceptive sensors resulting in the generation of NMPs. The detection threshold of 20.6% CO 2 (v/v) was surprisingly low, i.e. 22% CO 2 (v/v) below the NMP threshold. The involvement of newly discovered α-gustducin positive trigeminal chemosensory cells in CO 2 detection is hypothesized.

  • Sensitivity of the negative mucosal potential to the trigeminal Target Stimulus CO(2).
    Brain research, 2002
    Co-Authors: Norbert Thurauf, Michael Gunther, E Pauli, G Kobal
    Abstract:

    CO(2) is frequently used in an experimental pain model and in imaging studies investigating the central processing of trigeminal nociceptive information because of its specific trigeminal stimulation properties. The aim of the current study was (1) to investigate the sensitivity of the NMP to small increments of CO(2) Stimulus concentrations (3% CO(2), v/v) and (2) to characterize the sensory input of CO(2) by determining NMP, detection and pain thresholds and by registering subjective verbal descriptions. Ten subjects participated in the first experimental sessions investigating NMP responses to stimuli of 62, 65, 68% CO(2) (v/v) (Stimulus duration: 1000 ms). Our statistical analysis revealed a dose-dependent increase of the NMP amplitudes and areas under the curves (AUCs) demonstrating the high dynamic resolution of the NMP. Ten subjects participated in the second experimental sessions determining thresholds for NMP, detection and pain (Stimulus duration: 1000 ms). MANOVA analysis revealed significantly different thresholds for detection, NMP and subjective pain judgements (mean and S.D. as percentage CO(2) (v/v): detection: 20.6+/-9.6, NMP: 42.6+/-12.5, pain: 50.4+/-12.0). We could demonstrate the existence of a prepain range below subjective pain thresholds with activation of trigeminal nociceptive sensors resulting in the generation of NMPs. The detection threshold of 20.6% CO(2) (v/v) was surprisingly low, i.e. 22% CO(2) (v/v) below the NMP threshold. The involvement of newly discovered alpha-gustducin positive trigeminal chemosensory cells in CO(2) detection is hypothesized.

Ivan Rektor - One of the best experts on this subject based on the ideXlab platform.

  • effective connectivity in Target Stimulus processing a dynamic causal modeling study of visual oddball task
    NeuroImage, 2007
    Co-Authors: Milan Brazdil, Michal Mikl, Radek Marecek, Petr Krupa, Ivan Rektor
    Abstract:

    Abstract Purpose To investigate the fundamental connectivity architecture of neural structures involved in the goal-directed processing of Target events. Methods Twenty healthy volunteers underwent event-related functional magnetic resonance imaging (fMRI) while performing a standard oddball task. In the task, two types of visual stimuli – rare (Target) and frequent – were randomly presented, and subjects were instructed to mentally count the Target stimuli. Dynamic causal modeling (DCM), in combination with Bayes factors was used to compare competing neurophysiological models with different intrinsic connectivity structures and input regions within the network of brain regions underlying Target Stimulus processing. Results Conventional analysis of fMRI data revealed significantly greater activation in response to the Target stimuli (in comparison to the frequent stimuli) in several brain regions, including the intraparietal sulci and supramarginal gyri, the anterior and posterior cingulate gyri, the inferior and middle frontal gyri, the superior temporal sulcus, the precuneus/cuneus, and the subcortical grey matter (caudate and thalamus). The most extensive cortical activations were found in the right intraparietal sulcus (IPS), the anterior cingulate cortex (ACC), and the right lateral prefrontal cortex (PFC). These three regions were entered into the DCM. A comparison on a group level revealed that the dynamic causal models in which the ACC and alternatively the IPS served as input regions were superior to a model in which the PFC was assumed to receive external inputs. No significant difference was observed between the fully connected models with ACC and IPS as input regions. Subsequent analysis of the intrinsic connectivity within two investigated models (IPS and ACC) disclosed significant parallel forward connections from the IPS to the frontal areas and from the ACC to the PFC and the IPS. Conclusion Our findings indicate that during Target Stimulus processing there is a bidirectional frontoparietal information flow, very likely reflecting parallel activation of two distinct but partially overlapping attentional or attentional/event-encoding neural systems. Additionally, a simple hierarchy within the right frontal lobe is suggested with the ACC exerting influence over the PFC.

  • Temporal characteristics of cortical activation induced bynon-Target Stimulus in visual oddball setup (intra-cerebralstudy in humans)
    2003
    Co-Authors: Miloslav Kukleta, Milan Brazdil, Robert Roman, Ivan Rektor
    Abstract:

    Temporal characteristics of cortical activation induced by non-Target Stimulus in visual oddball were studied in epileptic patients.

Paul A. S. Breslin - One of the best experts on this subject based on the ideXlab platform.

  • Selective removal of a Target Stimulus localized by taste in humans.
    Chemical senses, 2000
    Co-Authors: Jeannine F. Delwiche, Melissa F. Lera, Paul A. S. Breslin
    Abstract:

    Recent studies have shown that people can localize a punctate gustatory Stimulus on the lingual epithelium in the absence of discriminative tactile cues. The present studies examined the human ability to localize taste sensations on the tongue and to use this information to remove selectively a Target Stimulus (a flavored, 1 cm 3 gelatin cube) from the mouth when presented with non-Target distractors that vary in number and taste. Findings indicate that humans are capable of localizing and removing either an aversive or an appetitive gustatory Target from a field of tactile distractors via taste sensations alone, although this ability diminishes as the number of distractors increases (implicating serial searches, rather than parallel). In addition, humans can localize and selectively remove a Target taste in the presence of distractors of another distinct taste quality. Under these conditions performance is either unaffected or reduced, which indicates that contrast with the distinct taste of the distractors does not enhance performance. Humans also are capable of removing a nearly tasteless cube from a field of flavored distractors, but this is clearly a more difficult task, suggesting that ‘tactile capture’ of taste occurs for the tasteless Target cube and interferes with the localization of taste. Finally, perceived suprathreshold Stimulus intensity did not seem to be related to the ability to localize and remove a Target Stimulus via taste sensations and failed to account for variations in performance across individuals.

Norbert Thurauf - One of the best experts on this subject based on the ideXlab platform.

  • sensitivity of the negative mucosal potential to the trigeminal Target Stimulus co2
    Brain Research, 2002
    Co-Authors: Norbert Thurauf, Michael Gunther, E Pauli, G Kobal
    Abstract:

    CO 2 is frequently used in an experimental pain model and in imaging studies investigating the central processing of trigeminal nociceptive information because of its specific trigeminal stimulation properties. The aim of the current study was (1) to investigate the sensitivity of the NMP to small increments of CO 2 Stimulus concentrations (3% CO 2 , v/v) and (2) to characterize the sensory input of CO 2 by determining NMP, detection and pain thresholds and by registering subjective verbal descriptions. Ten subjects participated in the first experimental sessions investigating NMP responses to stimuli of 62, 65, 68% CO 2 (v/v) (Stimulus duration: 1000 ms). Our statistical analysis revealed a dose-dependent increase of the NMP amplitudes and areas under the curves (AUCs) demonstrating the high dynamic resolution of the NMP. Ten subjects participated in the second experimental sessions determining thresholds for NMP, detection and pain (Stimulus duration: 1000 ms). MANOVA analysis revealed significantly different thresholds for detection, NMP and subjective pain judgements (mean and S.D. as percentage CO 2 (v/v): detection: 20.6±9.6, NMP: 42.6±12.5, pain: 50.4±12.0). We could demonstrate the existence of a prepain range below subjective pain thresholds with activation of trigeminal nociceptive sensors resulting in the generation of NMPs. The detection threshold of 20.6% CO 2 (v/v) was surprisingly low, i.e. 22% CO 2 (v/v) below the NMP threshold. The involvement of newly discovered α-gustducin positive trigeminal chemosensory cells in CO 2 detection is hypothesized.

  • Sensitivity of the negative mucosal potential to the trigeminal Target Stimulus CO(2).
    Brain research, 2002
    Co-Authors: Norbert Thurauf, Michael Gunther, E Pauli, G Kobal
    Abstract:

    CO(2) is frequently used in an experimental pain model and in imaging studies investigating the central processing of trigeminal nociceptive information because of its specific trigeminal stimulation properties. The aim of the current study was (1) to investigate the sensitivity of the NMP to small increments of CO(2) Stimulus concentrations (3% CO(2), v/v) and (2) to characterize the sensory input of CO(2) by determining NMP, detection and pain thresholds and by registering subjective verbal descriptions. Ten subjects participated in the first experimental sessions investigating NMP responses to stimuli of 62, 65, 68% CO(2) (v/v) (Stimulus duration: 1000 ms). Our statistical analysis revealed a dose-dependent increase of the NMP amplitudes and areas under the curves (AUCs) demonstrating the high dynamic resolution of the NMP. Ten subjects participated in the second experimental sessions determining thresholds for NMP, detection and pain (Stimulus duration: 1000 ms). MANOVA analysis revealed significantly different thresholds for detection, NMP and subjective pain judgements (mean and S.D. as percentage CO(2) (v/v): detection: 20.6+/-9.6, NMP: 42.6+/-12.5, pain: 50.4+/-12.0). We could demonstrate the existence of a prepain range below subjective pain thresholds with activation of trigeminal nociceptive sensors resulting in the generation of NMPs. The detection threshold of 20.6% CO(2) (v/v) was surprisingly low, i.e. 22% CO(2) (v/v) below the NMP threshold. The involvement of newly discovered alpha-gustducin positive trigeminal chemosensory cells in CO(2) detection is hypothesized.

Michael Gunther - One of the best experts on this subject based on the ideXlab platform.

  • sensitivity of the negative mucosal potential to the trigeminal Target Stimulus co2
    Brain Research, 2002
    Co-Authors: Norbert Thurauf, Michael Gunther, E Pauli, G Kobal
    Abstract:

    CO 2 is frequently used in an experimental pain model and in imaging studies investigating the central processing of trigeminal nociceptive information because of its specific trigeminal stimulation properties. The aim of the current study was (1) to investigate the sensitivity of the NMP to small increments of CO 2 Stimulus concentrations (3% CO 2 , v/v) and (2) to characterize the sensory input of CO 2 by determining NMP, detection and pain thresholds and by registering subjective verbal descriptions. Ten subjects participated in the first experimental sessions investigating NMP responses to stimuli of 62, 65, 68% CO 2 (v/v) (Stimulus duration: 1000 ms). Our statistical analysis revealed a dose-dependent increase of the NMP amplitudes and areas under the curves (AUCs) demonstrating the high dynamic resolution of the NMP. Ten subjects participated in the second experimental sessions determining thresholds for NMP, detection and pain (Stimulus duration: 1000 ms). MANOVA analysis revealed significantly different thresholds for detection, NMP and subjective pain judgements (mean and S.D. as percentage CO 2 (v/v): detection: 20.6±9.6, NMP: 42.6±12.5, pain: 50.4±12.0). We could demonstrate the existence of a prepain range below subjective pain thresholds with activation of trigeminal nociceptive sensors resulting in the generation of NMPs. The detection threshold of 20.6% CO 2 (v/v) was surprisingly low, i.e. 22% CO 2 (v/v) below the NMP threshold. The involvement of newly discovered α-gustducin positive trigeminal chemosensory cells in CO 2 detection is hypothesized.

  • Sensitivity of the negative mucosal potential to the trigeminal Target Stimulus CO(2).
    Brain research, 2002
    Co-Authors: Norbert Thurauf, Michael Gunther, E Pauli, G Kobal
    Abstract:

    CO(2) is frequently used in an experimental pain model and in imaging studies investigating the central processing of trigeminal nociceptive information because of its specific trigeminal stimulation properties. The aim of the current study was (1) to investigate the sensitivity of the NMP to small increments of CO(2) Stimulus concentrations (3% CO(2), v/v) and (2) to characterize the sensory input of CO(2) by determining NMP, detection and pain thresholds and by registering subjective verbal descriptions. Ten subjects participated in the first experimental sessions investigating NMP responses to stimuli of 62, 65, 68% CO(2) (v/v) (Stimulus duration: 1000 ms). Our statistical analysis revealed a dose-dependent increase of the NMP amplitudes and areas under the curves (AUCs) demonstrating the high dynamic resolution of the NMP. Ten subjects participated in the second experimental sessions determining thresholds for NMP, detection and pain (Stimulus duration: 1000 ms). MANOVA analysis revealed significantly different thresholds for detection, NMP and subjective pain judgements (mean and S.D. as percentage CO(2) (v/v): detection: 20.6+/-9.6, NMP: 42.6+/-12.5, pain: 50.4+/-12.0). We could demonstrate the existence of a prepain range below subjective pain thresholds with activation of trigeminal nociceptive sensors resulting in the generation of NMPs. The detection threshold of 20.6% CO(2) (v/v) was surprisingly low, i.e. 22% CO(2) (v/v) below the NMP threshold. The involvement of newly discovered alpha-gustducin positive trigeminal chemosensory cells in CO(2) detection is hypothesized.