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Ottmar V. Lipp - One of the best experts on this subject based on the ideXlab platform.
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The effect of Stimulus Modality and task difficulty on attentional modulation of blink startle.
Psychophysiology, 2004Co-Authors: David L. Neumann, Ottmar V. Lipp, Meredith J. MchughAbstract:The effects of the sensory Modality of the lead Stimulus and of task difficulty on attentional modulation of the electrical and acoustic blink reflex were examined. Participants performed a discrimination and counting task with either two acoustic, two visual, or two tactile lead stimuli. In Experiment 1, facilitation of the electrically elicited blink was greater during task-relevant than during task-irrelevant lead stimuli. Increasing task difficulty enhanced magnitude facilitation for acoustic lead stimuli. In Experiment 2, acoustic blink facilitation was greater during task-relevant lead stimuli, but was unaffected by task difficulty. Experiment 3 showed that a further increase in task difficulty did not affect acoustic blink facilitation during visual lead stimuli. The observation that blink reflexes are facilitated by attention in the present task domain is consistent across a range of Stimulus Modality and task difficulty conditions.
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The effects of lead Stimulus and reflex Stimulus Modality on modulation of the blink reflex at very short, short, and long lead intervals
Perception & psychophysics, 2004Co-Authors: David L. Neumann, Ottmar V. Lipp, Natalie R. PretoriusAbstract:The blink reflex is modulated if a weak lead Stimulus precedes the blink-eliciting Stimulus. In two experiments, we examined the effects of the sensory Modality of the lead and blink-eliciting stimuli on blink modulation. Acoustic, visual, or tactile lead stimuli were followed by an acoustic (Experiment 1) or an electrotactile (Experiment 2) blink-eliciting Stimulus at lead intervals of -30, 0, 30, 60, 120, 240, 360, and 4,500 msec. The inhibition of blink magnitude at the short (60- to 360-msec) lead intervals and the facilitation of blink magnitude at the long (4,500-msec) lead interval observed for each lead Stimulus Modality was relatively unaffected by the blink-eliciting Stimulus Modality. The facilitation of blink magnitude at the very short (-30- to 30-msec) lead intervals was dependent on the combination of the lead and the blink-eliciting Stimulus modalities. Modality specific and nonspecific processes operate at different levels of perceptual processing.
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Attentional blink modulation in a reaction time task: performance feedback, warning Stimulus Modality, and task difficulty.
Biological psychology, 2003Co-Authors: Ottmar V. Lipp, S. A. HardwickAbstract:The present research investigated the effect of performance feedback on the modulation of the acoustic startle reflex in a Go/NoGo reaction time task. Experiment 1 (n=120) crossed warning Stimulus Modality (acoustic, visual, and tactile) with the provision of feedback in a between subject design. Provision of performance feedback increased the number of errors committed and reduced reaction time, but did not affect blink modulation significantly. Attentional blink latency and magnitude modulation was larger during acoustic than during visual and larger during visual than during tactile warning stimuli. In comparison to control blinks, latency shortening was significant in all Modality conditions whereas magnitude facilitation was not significant during tactile warning stimuli. Experiment 2 (n=80) employed visual warning stimuli only and crossed the provision of feedback with task difficulty. Feedback and difficulty affected accuracy and reaction time. Whereas blink latency shortening was not affected, blink magnitude modulation was smallest in the Easy/No Feedback and the Difficult/Feedback conditions.
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Lead Stimulus Modality change and the attentional modulation of the acoustic and electrical blink reflex.
Biological psychology, 2003Co-Authors: Ottmar V. Lipp, David L. Neumann, Meredith J. MchughAbstract:Two experiments investigated the effects of the sensory Modality of the lead and of the blink-eliciting Stimulus during lead Stimulus Modality change on blink modulation at lead intervals of 2500 and 3500 ms. Participants were presented with acoustic, visual, or tactile change stimuli after habituation training with lead stimuli from the same or a different sensory Modality. In Experiment 1, latency and magnitude of the acoustic blink were facilitated during a change to acoustic or visual lead stimuli, but not during a change to tactile lead stimuli. After habituation to acoustic lead stimuli, blink magnitude was smaller during tactile change stimuli than during habituation stimuli. The latter finding was replicated in Experiment 2 in which blink was elicited by electrical stimulation of the trigeminal nerve. The consistency of the findings across different combinations of lead Stimulus and blink-eliciting Stimulus modalities does not support a Modality-specific account of attentional blink modulation. Rather, blink modulation during generalized orienting reflects Modality non-specific processes, although modulation may not always be found during tactile lead stimuli.
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The effect of warning Stimulus Modality on blink startle modification in reaction time tasks
Psychophysiology, 2000Co-Authors: Ottmar V. Lipp, David A.t. Siddle, Patricia J. DallAbstract:The present study investigated the effects of lead Stimulus Modality on modification of the acoustic startle reflex during three reaction time tasks. In Experiment 1, participants (N = 48) were required to press a button at the offset of one Stimulus (task relevant) and to ignore presentations of a second (task irrelevant). Two tones that differed in pitch or two lights served as signal stimuli. Blink startle was elicited during some of the stimuli and during interStimulus intervals. Skin conductance responses were larger during task-relevant stimuli in both groups. Larger blink facilitation during task-relevant stimuli was found only in the group presented with auditory stimuli, whereas larger blink latency shortening during task-relevant stimuli was found in both groups. Experiment 2 (N = 32) used only a task-relevant Stimulus. Blink magnitude facilitation was significant only in the group presented with tones, whereas blink latency shortening was significant in both groups. Experiment 3 (N = 80) used a go/nogo task that required participants to press a button if one element of a compound Stimulus ended before the second, but not if the asynchrony was reversed. The offset asynchrony was varied between groups as a manipulation of task difficulty. Startle magnitude facilitation was larger during acoustic than during visual stimuli and larger in the easy condition. The present data indicate that startle facilitation in a reaction time task is affected by Stimulus Modality and by task demands. The effects of the task demands seem to be independent of lead Stimulus Modality.
Patricia J. Dall - One of the best experts on this subject based on the ideXlab platform.
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The effect of warning Stimulus Modality on blink startle modification in reaction time tasks
Psychophysiology, 2000Co-Authors: Ottmar V. Lipp, David A.t. Siddle, Patricia J. DallAbstract:The present study investigated the effects of lead Stimulus Modality on modification of the acoustic startle reflex during three reaction time tasks. In Experiment 1, participants (N = 48) were required to press a button at the offset of one Stimulus (task relevant) and to ignore presentations of a second (task irrelevant). Two tones that differed in pitch or two lights served as signal stimuli. Blink startle was elicited during some of the stimuli and during interStimulus intervals. Skin conductance responses were larger during task-relevant stimuli in both groups. Larger blink facilitation during task-relevant stimuli was found only in the group presented with auditory stimuli, whereas larger blink latency shortening during task-relevant stimuli was found in both groups. Experiment 2 (N = 32) used only a task-relevant Stimulus. Blink magnitude facilitation was significant only in the group presented with tones, whereas blink latency shortening was significant in both groups. Experiment 3 (N = 80) used a go/nogo task that required participants to press a button if one element of a compound Stimulus ended before the second, but not if the asynchrony was reversed. The offset asynchrony was varied between groups as a manipulation of task difficulty. Startle magnitude facilitation was larger during acoustic than during visual stimuli and larger in the easy condition. The present data indicate that startle facilitation in a reaction time task is affected by Stimulus Modality and by task demands. The effects of the task demands seem to be independent of lead Stimulus Modality.
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The effects of change in lead Stimulus Modality on the modulation of acoustic blink startle
Psychophysiology, 2000Co-Authors: Ottmar V. Lipp, David A.t. Siddle, Patricia J. DallAbstract:In two experiments we investigated the effect of generalized orienting induced by changing the Modality of the lead Stimulus on the modulation of blink reflexes elicited by acoustic stimuli. In Experiment 1 (n = 32), participants were presented with acoustic or visual change stimuli after habituation training with tactile lead stimuli. In Experiment 2 (n = 64), Modality of the lead Stimulus (acoustic vs. visual) was crossed with experimental condition (change vs. no change). Lead Stimulus change resulted in increased electrodermal orienting in both experiments. Blink latency shortening and blink magnitude facilitation increased from habituation to change trials regardless of whether the change Stimulus was presented in the same or in a different Modality as the reflex-eliciting Stimulus. These results are not consistent with Modality-specific accounts of attentional startle modulation.
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Effects of Stimulus Modality and task condition on blink startle modification and on electrodermal responses
Psychophysiology, 1998Co-Authors: Ottmar V. Lipp, David A.t. Siddle, Patricia J. DallAbstract:Participants in Experiments 1 and 2 performed a discrimination and counting task to assess the effect of lead Stimulus Modality on attentional modification of the acoustic startle reflex. Modality of the discrimination stimuli was changed across subjects. Electrodermal responses were larger during task-relevant stimuli than during task-irrelevant stimuli in all conditions. Larger blink magnitude facilitation was found during auditory and visual task-relevant stimuli, but not for tactile stimuli. Experiment 3 used acoustic, visual, and tactile conditioned stimuli (CSs) in differential conditioning with an aversive unconditioned Stimulus (US). Startle magnitude facilitation and electrodermal responses were larger during a CS that preceded the US than during a CS that was presented alone regardless of lead Stimulus Modality. Although not unequivocal, the present data pose problems for attentional accounts of blink modification that emphasize the importance of lead Stimulus Modality.
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The effect of unconditional Stimulus Modality and intensity on blink startle and electrodermal responses
Psychophysiology, 1997Co-Authors: David A.t. Siddle, Ottmar V. Lipp, Patricia J. DallAbstract:Attentional accounts of blink facilitation during Pavlovian conditioning predict enhanced reflexes if reflex and unconditional stimuli (US) are from the same Modality. Emotional accounts emphasize the importance of US intensity. In Experiment 1, we crossed US Modality (tone vs, shock) and intensity in a 2 X 2 between-subjects design. US intensity but not US Modality affected blink facilitation. Tn Experiment 2, we demonstrated that the results from Experiment 1 were not due to the motor task requirements employed. In Experiment 3, we used a within-subjects design to investigate the effects of US Modality and intensity. Contrary to predictions derived from an attentional account, blink facilitation was larger during conditional stimuli that preceded shock than during those that preceded tones. The present results are not consistent with an attentional account of blink facilitation during Pavlovian conditioning in humans.
Sebastian Halder - One of the best experts on this subject based on the ideXlab platform.
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Stimulus Modality influences session-to-session transfer of training effects in auditory and tactile streaming-based P300 brain-computer interfaces.
Scientific reports, 2020Co-Authors: P Ziebell, J Stümpfig, Matthias Eidel, Sonja C. Kleih, Andrea Kübler, M E Latoschik, Sebastian HalderAbstract:Despite recent successes, patients suffering from locked-in syndrome (LIS) still struggle to communicate using vision-independent brain-computer interfaces (BCIs). In this study, we compared auditory and tactile BCIs, regarding training effects and cross-Stimulus-Modality transfer effects, when switching between Stimulus modalities. We utilized a streaming-based P300 BCI, which was developed as a low workload approach to prevent potential BCI-inefficiency. We randomly assigned 20 healthy participants to two groups. The participants received three sessions of training either using an auditory BCI or using a tactile BCI. In an additional fourth session, BCI versions were switched to explore possible cross-Stimulus-Modality transfer effects. Both BCI versions could be operated successfully in the first session by the majority of the participants, with the tactile BCI being experienced as more intuitive. Significant training effects were found mostly in the auditory BCI group and strong evidence for a cross-Stimulus-Modality transfer occurred for the auditory training group that switched to the tactile version but not vice versa. All participants were able to control at least one BCI version, suggesting that the investigated paradigms are generally feasible and merit further research into their applicability with LIS end-users. Individual preferences regarding Stimulus Modality should be considered.
David A.t. Siddle - One of the best experts on this subject based on the ideXlab platform.
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The effect of warning Stimulus Modality on blink startle modification in reaction time tasks
Psychophysiology, 2000Co-Authors: Ottmar V. Lipp, David A.t. Siddle, Patricia J. DallAbstract:The present study investigated the effects of lead Stimulus Modality on modification of the acoustic startle reflex during three reaction time tasks. In Experiment 1, participants (N = 48) were required to press a button at the offset of one Stimulus (task relevant) and to ignore presentations of a second (task irrelevant). Two tones that differed in pitch or two lights served as signal stimuli. Blink startle was elicited during some of the stimuli and during interStimulus intervals. Skin conductance responses were larger during task-relevant stimuli in both groups. Larger blink facilitation during task-relevant stimuli was found only in the group presented with auditory stimuli, whereas larger blink latency shortening during task-relevant stimuli was found in both groups. Experiment 2 (N = 32) used only a task-relevant Stimulus. Blink magnitude facilitation was significant only in the group presented with tones, whereas blink latency shortening was significant in both groups. Experiment 3 (N = 80) used a go/nogo task that required participants to press a button if one element of a compound Stimulus ended before the second, but not if the asynchrony was reversed. The offset asynchrony was varied between groups as a manipulation of task difficulty. Startle magnitude facilitation was larger during acoustic than during visual stimuli and larger in the easy condition. The present data indicate that startle facilitation in a reaction time task is affected by Stimulus Modality and by task demands. The effects of the task demands seem to be independent of lead Stimulus Modality.
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The effects of change in lead Stimulus Modality on the modulation of acoustic blink startle
Psychophysiology, 2000Co-Authors: Ottmar V. Lipp, David A.t. Siddle, Patricia J. DallAbstract:In two experiments we investigated the effect of generalized orienting induced by changing the Modality of the lead Stimulus on the modulation of blink reflexes elicited by acoustic stimuli. In Experiment 1 (n = 32), participants were presented with acoustic or visual change stimuli after habituation training with tactile lead stimuli. In Experiment 2 (n = 64), Modality of the lead Stimulus (acoustic vs. visual) was crossed with experimental condition (change vs. no change). Lead Stimulus change resulted in increased electrodermal orienting in both experiments. Blink latency shortening and blink magnitude facilitation increased from habituation to change trials regardless of whether the change Stimulus was presented in the same or in a different Modality as the reflex-eliciting Stimulus. These results are not consistent with Modality-specific accounts of attentional startle modulation.
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Effects of Stimulus Modality and task condition on blink startle modification and on electrodermal responses
Psychophysiology, 1998Co-Authors: Ottmar V. Lipp, David A.t. Siddle, Patricia J. DallAbstract:Participants in Experiments 1 and 2 performed a discrimination and counting task to assess the effect of lead Stimulus Modality on attentional modification of the acoustic startle reflex. Modality of the discrimination stimuli was changed across subjects. Electrodermal responses were larger during task-relevant stimuli than during task-irrelevant stimuli in all conditions. Larger blink magnitude facilitation was found during auditory and visual task-relevant stimuli, but not for tactile stimuli. Experiment 3 used acoustic, visual, and tactile conditioned stimuli (CSs) in differential conditioning with an aversive unconditioned Stimulus (US). Startle magnitude facilitation and electrodermal responses were larger during a CS that preceded the US than during a CS that was presented alone regardless of lead Stimulus Modality. Although not unequivocal, the present data pose problems for attentional accounts of blink modification that emphasize the importance of lead Stimulus Modality.
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The effect of unconditional Stimulus Modality and intensity on blink startle and electrodermal responses
Psychophysiology, 1997Co-Authors: David A.t. Siddle, Ottmar V. Lipp, Patricia J. DallAbstract:Attentional accounts of blink facilitation during Pavlovian conditioning predict enhanced reflexes if reflex and unconditional stimuli (US) are from the same Modality. Emotional accounts emphasize the importance of US intensity. In Experiment 1, we crossed US Modality (tone vs, shock) and intensity in a 2 X 2 between-subjects design. US intensity but not US Modality affected blink facilitation. Tn Experiment 2, we demonstrated that the results from Experiment 1 were not due to the motor task requirements employed. In Experiment 3, we used a within-subjects design to investigate the effects of US Modality and intensity. Contrary to predictions derived from an attentional account, blink facilitation was larger during conditional stimuli that preceded shock than during those that preceded tones. The present results are not consistent with an attentional account of blink facilitation during Pavlovian conditioning in humans.
Gian Domenico Iannetti - One of the best experts on this subject based on the ideXlab platform.
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Dishabituation of Laser-evoked EEG Responses: Dissecting the Effect of Certain and Uncertain Changes in Stimulus Modality
Journal of Cognitive Neuroscience, 2011Co-Authors: Elia Valentini, Diana M. E. Torta, André Mouraux, Gian Domenico IannettiAbstract:The repetition of nociceptive stimuli of identical Modality, intensity, and location at short and constant interStimulus intervals (ISIs) determines a strong habituation of the corresponding EEG responses, without affecting the subjective perception of pain. To understand what determines this response habituation, we (i) examined the effect of introducing a change in the Modality of the repeated Stimulus, and (ii) dissected the relative contribution of bottom–up, Stimulus-driven changes in Modality and top–down, cognitive expectations of such a change, on both laser-evoked and auditory-evoked EEG responses. Multichannel EEG was recorded while participants received trains of three stimuli (S1–S2–S3, a triplet) delivered to the hand dorsum at 1-sec ISI. S3 belonged either to the same Modality as S1 and S2 or to the other Modality. In addition, participants were either explicitly informed or not informed of the Modality of S3. We found that introducing a change in Stimulus Modality produced a significant dishabituation of the laser-evoked N1, N2, and P2 waves; the auditory N1 and P2 waves; and the laser- and auditory-induced event-related synchronization and desynchronization. In contrast, the lack of explicit knowledge of a possible change in the sensory Modality of the Stimulus (i.e., uncertainty) only increased the ascending portion of the laser-evoked and auditory-evoked P2 wave. Altogether, these results indicate that bottom–up novelty resulting from the change of Stimulus Modality, and not top–down cognitive expectations, plays a major role in determining the habituation of these brain responses.
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functional characterisation of sensory erps using probabilistic ica effect of Stimulus Modality and Stimulus location
Clinical Neurophysiology, 2010Co-Authors: Meng Liang, André Mouraux, Gian Domenico Iannetti, V Chan, Colin BlakemoreAbstract:Objective: To decompose sensory event-related brain potentials (ERPs) into a set of independent components according to the Modality and the spatial location of the eliciting sensory Stimulus, and thus provide a quantitative analysis of their underlying components. Methods: Auditory, somatosensory and visual ERPs were recorded from 124 electrodes in thirteen healthy participants. Probabilistic Independent Component Analysis (P-ICA) was used to decompose these sensory ERPs into a set of independent components according to the Modality (auditory, somatosensory, visual or multimodal) and the spatial location (left or right side) of the eliciting Stimulus. Results: Middle-latency sensory ERPs were explained by a large contribution of multimodal neural activities, and a smaller contribution of unimodal neural activities. While a significant fraction of unimodal neural activities were dependent on the location of the eliciting Stimulus, virtually all multimodal neural activities were not (i.e. their scalp distributions and time courses were not different when stimuli were presented on the left and right sides). Conclusion: These findings show that P-ICA can be used to dissect effectively sensory ERPs into physiologically meaningful components, and indicate a new approach for exploring the effect of various experimental modulations of sensory ERPs. Significance: This approach offers a better understanding of the functional significance of sensory ERPs. (C) 2009 International Federation of Clinical Neurophysiology. Published by Elsevier Ireland Ltd. All rights reserved.
