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Rufin Vanrullen - One of the best experts on this subject based on the ideXlab platform.

  • individual alpha peak frequency predicts 10 hz flicker effects on selective attention
    The Journal of Neuroscience, 2017
    Co-Authors: Rasa Gulbinaite, Tara Van Viegen, Martijn Wieling, Michael X Cohen, Rufin Vanrullen
    Abstract:

    Rhythmic visual stimulation (“flicker”) is primarily used to “tag” processing of low-level visual and high-level cognitive phenomena. However, preliminary evidence suggests that flicker may also entrain endogenous brain oscillations, thereby modulating cognitive processes supported by those brain rhythms. Here we tested the interaction between 10 Hz flicker and endogenous alpha-band (∼10 Hz) oscillations during a selective visuospatial attention Task. We recorded EEG from human participants (both genders) while they performed a modified Eriksen Flanker Task in which distractors and targets flickered within (10 Hz) or outside (7.5 or 15 Hz) the alpha band. By using a combination of EEG source separation, time-frequency, and single-trial linear mixed effects modeling, we demonstrate that 10 Hz flicker interfered with stimulus processing more on incongruent than congruent trials (high vs. low selective attention demands). Crucially, the effect of 10 Hz flicker on Task performance was predicted by the distance between 10 Hz and individual alpha peak frequency (estimated during the Task). Finally, the flicker effect on Task performance was more strongly predicted by EEG flicker responses during stimulus processing than during preparation for the upcoming stimulus, suggesting that 10 Hz flicker interfered more with reactive than proactive selective attention. These findings are consistent with our hypothesis that visual flicker entrained endogenous alpha-band networks, which in turn impaired Task performance. Our findings also provide novel evidence for frequency-dependent exogenous modulation of cognition that is determined by the correspondence between the exogenous flicker frequency and the endogenous brain rhythms. SIGNIFICANCE STATEMENT Here we provide novel evidence that the interaction between exogenous rhythmic visual stimulation and endogenous brain rhythms can have frequency-specific behavioral effects. We show that alpha-band (10 Hz) flicker impairs stimulus processing in a selective attention Task when the stimulus flicker rate matches individual alpha peak frequency. The effect of sensory flicker on Task performance was stronger when selective attention demands were high, and was stronger during stimulus processing and response selection compared to the pre-stimulus anticipatory period. These findings provide novel evidence that frequency-specific sensory flicker affects online attentional processing, and also demonstrate that the correspondence between exogenous and endogenous rhythms is an overlooked prerequisite when testing for frequency-specific cognitive effects of flicker.

  • individual alpha peak frequency predicts 10 hz flicker effects on selective attention
    bioRxiv, 2017
    Co-Authors: Rasa Gulbinaite, Tara Van Viegen, Martijn Wieling, Michael X Cohen, Rufin Vanrullen
    Abstract:

    Rhythmic visual stimulation ("flicker") is primarily used to "tag" processing of low-level visual and high-level cognitive phenomena. However, preliminary evidence suggests that flicker may also entrain endogenous brain oscillations, thereby modulating cognitive processes supported by those brain rhythms. Here we tested the interaction between 10 Hz flicker and endogenous alpha-band (~10 Hz) oscillations during a selective visuospatial attention Task. We recorded EEG from human participants (both genders) while they performed a modified Eriksen Flanker Task in which distractors and targets flickered within (10 Hz) or outside (7.5 or 15 Hz) the alpha band. By using a combination of EEG source separation, time-frequency, and single-trial linear mixed effects modeling, we demonstrate that 10 Hz flicker interfered with stimulus processing more on incongruent than congruent trials (high vs. low selective attention demands). Crucially, the effect of 10 Hz flicker on Task performance was predicted by the distance between 10 Hz and individual alpha peak frequency (estimated during the Task). Finally, the flicker effect on Task performance was more strongly predicted by EEG flicker responses during stimulus processing than during preparation for the upcoming stimulus, suggesting that 10 Hz flicker interfered more with reactive than proactive selective attention. These findings are consistent with our hypothesis that visual flicker entrained endogenous alpha-band networks, which in turn impaired Task performance. Our findings also provide novel evidence for frequency-dependent exogenous modulation of cognition that is determined by the correspondence between the exogenous flicker frequency and the endogenous brain rhythms.

Rasa Gulbinaite - One of the best experts on this subject based on the ideXlab platform.

  • individual alpha peak frequency predicts 10 hz flicker effects on selective attention
    The Journal of Neuroscience, 2017
    Co-Authors: Rasa Gulbinaite, Tara Van Viegen, Martijn Wieling, Michael X Cohen, Rufin Vanrullen
    Abstract:

    Rhythmic visual stimulation (“flicker”) is primarily used to “tag” processing of low-level visual and high-level cognitive phenomena. However, preliminary evidence suggests that flicker may also entrain endogenous brain oscillations, thereby modulating cognitive processes supported by those brain rhythms. Here we tested the interaction between 10 Hz flicker and endogenous alpha-band (∼10 Hz) oscillations during a selective visuospatial attention Task. We recorded EEG from human participants (both genders) while they performed a modified Eriksen Flanker Task in which distractors and targets flickered within (10 Hz) or outside (7.5 or 15 Hz) the alpha band. By using a combination of EEG source separation, time-frequency, and single-trial linear mixed effects modeling, we demonstrate that 10 Hz flicker interfered with stimulus processing more on incongruent than congruent trials (high vs. low selective attention demands). Crucially, the effect of 10 Hz flicker on Task performance was predicted by the distance between 10 Hz and individual alpha peak frequency (estimated during the Task). Finally, the flicker effect on Task performance was more strongly predicted by EEG flicker responses during stimulus processing than during preparation for the upcoming stimulus, suggesting that 10 Hz flicker interfered more with reactive than proactive selective attention. These findings are consistent with our hypothesis that visual flicker entrained endogenous alpha-band networks, which in turn impaired Task performance. Our findings also provide novel evidence for frequency-dependent exogenous modulation of cognition that is determined by the correspondence between the exogenous flicker frequency and the endogenous brain rhythms. SIGNIFICANCE STATEMENT Here we provide novel evidence that the interaction between exogenous rhythmic visual stimulation and endogenous brain rhythms can have frequency-specific behavioral effects. We show that alpha-band (10 Hz) flicker impairs stimulus processing in a selective attention Task when the stimulus flicker rate matches individual alpha peak frequency. The effect of sensory flicker on Task performance was stronger when selective attention demands were high, and was stronger during stimulus processing and response selection compared to the pre-stimulus anticipatory period. These findings provide novel evidence that frequency-specific sensory flicker affects online attentional processing, and also demonstrate that the correspondence between exogenous and endogenous rhythms is an overlooked prerequisite when testing for frequency-specific cognitive effects of flicker.

  • individual alpha peak frequency predicts 10 hz flicker effects on selective attention
    bioRxiv, 2017
    Co-Authors: Rasa Gulbinaite, Tara Van Viegen, Martijn Wieling, Michael X Cohen, Rufin Vanrullen
    Abstract:

    Rhythmic visual stimulation ("flicker") is primarily used to "tag" processing of low-level visual and high-level cognitive phenomena. However, preliminary evidence suggests that flicker may also entrain endogenous brain oscillations, thereby modulating cognitive processes supported by those brain rhythms. Here we tested the interaction between 10 Hz flicker and endogenous alpha-band (~10 Hz) oscillations during a selective visuospatial attention Task. We recorded EEG from human participants (both genders) while they performed a modified Eriksen Flanker Task in which distractors and targets flickered within (10 Hz) or outside (7.5 or 15 Hz) the alpha band. By using a combination of EEG source separation, time-frequency, and single-trial linear mixed effects modeling, we demonstrate that 10 Hz flicker interfered with stimulus processing more on incongruent than congruent trials (high vs. low selective attention demands). Crucially, the effect of 10 Hz flicker on Task performance was predicted by the distance between 10 Hz and individual alpha peak frequency (estimated during the Task). Finally, the flicker effect on Task performance was more strongly predicted by EEG flicker responses during stimulus processing than during preparation for the upcoming stimulus, suggesting that 10 Hz flicker interfered more with reactive than proactive selective attention. These findings are consistent with our hypothesis that visual flicker entrained endogenous alpha-band networks, which in turn impaired Task performance. Our findings also provide novel evidence for frequency-dependent exogenous modulation of cognition that is determined by the correspondence between the exogenous flicker frequency and the endogenous brain rhythms.

Lisa Tobel - One of the best experts on this subject based on the ideXlab platform.

  • conflict resolution in the Eriksen Flanker Task similarities and differences to the simon Task
    PLOS ONE, 2019
    Co-Authors: Ronald Hubner, Lisa Tobel
    Abstract:

    : In the Eriksen Flanker Task as well as in the Simon Task irrelevant activation produces a response conflict that has to be resolved by mental control mechanisms. Despite these similarities, however, the Tasks differ with respect to their delta functions, which express how the congruency effects develop with response time. The slope of the delta function is mostly positive for the Flanker Task, but negative for the Simon Task. Much effort has been spent to explain this difference and to investigate whether it results from Task-specific control. A prominent account is that the temporal overlap between irrelevant and relevant response activation is larger in the Flanker Task than in the Simon Task. To test this hypothesis, we increased the temporal distance in a Flanker Task by presenting the Flankers ahead of the target. This not only produced negatively sloped delta functions but also caused reversed congruency effects. We also conducted a Simon-Task experiment in which we varied the proportion of congruent stimuli. As a result, the delta function was negatively sloped only if the proportion was low. These results demonstrate that a long temporal distance is necessary but not sufficient for observing negatively sloped delta functions. Finally, we modeled the data with drift-diffusion models. Together, our results show that differently sloped delta functions can be produced with both Tasks. They further indicate that activation suppression is an important control mechanism that can be adapted rather flexibly to the control demands.

  • conflict resolution in the Eriksen Flanker Task similarities and differences to the simon Task
    PLOS ONE, 2019
    Co-Authors: Ronald Hubner, Lisa Tobel
    Abstract:

    : In the Eriksen Flanker Task as well as in the Simon Task irrelevant activation produces a response conflict that has to be resolved by mental control mechanisms. Despite these similarities, however, the Tasks differ with respect to their delta functions, which express how the congruency effects develop with response time. The slope of the delta function is mostly positive for the Flanker Task, but negative for the Simon Task. Much effort has been spent to explain this difference and to investigate whether it results from Task-specific control. A prominent account is that the temporal overlap between irrelevant and relevant response activation is larger in the Flanker Task than in the Simon Task. To test this hypothesis, we increased the temporal distance in a Flanker Task by presenting the Flankers ahead of the target. This not only produced negatively sloped delta functions but also caused reversed congruency effects. We also conducted a Simon-Task experiment in which we varied the proportion of congruent stimuli. As a result, the delta function was negatively sloped only if the proportion was low. These results demonstrate that a long temporal distance is necessary but not sufficient for observing negatively sloped delta functions. Finally, we modeled the data with drift-diffusion models. Together, our results show that differently sloped delta functions can be produced with both Tasks. They further indicate that activation suppression is an important control mechanism that can be adapted rather flexibly to the control demands.

Mike Wendt - One of the best experts on this subject based on the ideXlab platform.

  • more than attentional tuning investigating the mechanisms underlying practice gains and preparation in Task switching
    Frontiers in Psychology, 2017
    Co-Authors: Mike Wendt, Stina Klein, Tilo Strobach
    Abstract:

    In Task switching, participants perform trials of Task repetitions (i.e., the same Task is executed in consecutive trials) and Task switches (i.e., different Tasks are executed in consecutive trials) and the longer reaction times in switch trials in comparison to these times in repetition trials are referred to as switch costs. These costs are reduced by lengthening of an interval following a cue that indicates the upcoming Task; this effect demonstrated effective Task preparation. To investigate the role of Task switching practice for these preparation effects and Task switch costs, we applied a Task switching paradigm, involving two digit classification Tasks, in six successive practice sessions and varied the length of the preparation interval. To further examine practice-related processing alterations on preparation, particularly concerning the focusing of visual attention and control of response competition, we added an Eriksen Flanker Task in the initial and the final session. Unlike the two digit Tasks, which were always validly cued, the Eriksen Flanker Task occurred randomly after a cue that indicated one of the other two Tasks (i.e., invalid Task cuing). The results showed that, in the initial session, Task switch costs for the digit Tasks were reduced after a long preparation interval but this reduction disappeared after practice. This finding is consistent with the assumption of practice-related enhancement of preparation efficiency concerning non-perceptual Task processes. Flanker interference was larger after preparation for a Task repetition than for a Task switch and (regarding error rates) larger in the final than in the initial session. Possible mechanisms underlying these attentional modulations evoked by Task-sequence-dependent preparation and by Task switching practice are discussed.

  • adaptation to frequent conflict in the Eriksen Flanker Task
    Journal of Psychophysiology, 2011
    Co-Authors: Sascha Purmann, Stephanie Badde, Aquiles Lunarodriguez, Mike Wendt
    Abstract:

    We examined adaptation to frequent conflict in a Flanker Task using event-related potentials (ERPs). A prominent model of cognitive control suggests the fronto-central N2 as an indicator of conflict monitoring. Based on this model we predicted (1) an increased N2 amplitude for incompatible compared to compatible stimuli and (2) that this difference in N2 amplitude would be less pronounced under conditions of frequent conflict (high cognitive control). In this model, adaptation to frequent conflict is implemented as modulation of early visual processing. Traditionally, variations in processing selectivity in the Flanker Task have been related to a zoom lens model of visual attention. Therefore, we further predicted (3) effects of conflict frequency on early visual ERP components of the event-related potential, and (4) generalization of conflict adaptation due to increased conflict frequency in the Flanker Task to other visuospatial Tasks, intermixed within Flanker Task trials. Frequent conflict was associa...

  • adaptation to frequent conflict in the Eriksen Flanker Task
    Journal of Psychophysiology, 2011
    Co-Authors: Sascha Purmann, Stephanie Badde, Aquiles Lunarodriguez, Mike Wendt
    Abstract:

    We examined adaptation to frequent conflict in a Flanker Task using event-related potentials (ERPs). A prominent model of cognitive control suggests the fronto-central N2 as an indicator of conflict monitoring. Based on this model we predicted (1) an increased N2 amplitude for incompatible compared to compatible stimuli and (2) that this difference in N2 amplitude would be less pronounced under conditions of frequent conflict (high cognitive control). In this model, adaptation to frequent conflict is implemented as modulation of early visual processing. Traditionally, variations in processing selectivity in the Flanker Task have been related to a zoom lens model of visual attention. Therefore, we further predicted (3) effects of conflict frequency on early visual ERP components of the event-related potential, and (4) generalization of conflict adaptation due to increased conflict frequency in the Flanker Task to other visuospatial Tasks, intermixed within Flanker Task trials. Frequent conflict was associa...

Markus Kiefer - One of the best experts on this subject based on the ideXlab platform.

  • mechanisms underlying flexible adaptation of cognitive control behavioral and neuroimaging evidence in a Flanker Task
    Brain Research, 2011
    Co-Authors: Blandyna żurawska Vel Grajewska, Klaus Hoenig, Barbel Herrnberger, Markus Kiefer
    Abstract:

    Abstract Cognitive control can be adapted flexibly according to the conflict level in a given situation. In the Eriksen Flanker Task, interference evoked by Flankers is larger in conditions with a higher, rather than a lower proportion of compatible trials. Such compatibility ratio effects also occur for stimuli presented at two spatial locations suggesting that different cognitive control settings can be simultaneously maintained. However, the conditions and the neural correlates of this flexible adaptation of cognitive control are only poorly understood. In the present study, we further elucidated the mechanisms underlying the simultaneous maintenance of two cognitive control settings. In behavioral experiments, stimuli were presented centrally above and below fixation and hence processed by both hemispheres or lateralized to stimulate hemispheres differentially. The different compatibility ratio at two stimulus locations had a differential influence on the Flanker effect in both experiments. In an fMRI experiment, blocks with an identical compatibility ratio at two central spatial locations elicited stronger activity in a network of prefrontal and parietal brain areas, which are known to be involved in conflict resolution and cognitive control, as compared with blocks with a different compatibility ratio at the same spatial locations. This demonstrates that the simultaneous maintenance of two conflicting control settings vs. one single setting does not recruit additional neural circuits suggesting the involvement of one single cognitive control system. Instead a crosstalk between multiple control settings renders adaptation of cognitive control more efficient when only one uniform rather than two different control settings has to be simultaneously maintained.

  • physical fitness but not acute exercise modulates event related potential indices for executive control in healthy adolescents
    Brain Research, 2009
    Co-Authors: S Stroth, Sabine Kubesch, Katrin Dieterle, Martin Ruchsow, Ruediger Heim, Markus Kiefer
    Abstract:

    Physical activity and aerobic exercise in particular, promotes health and effective cognitive functioning. To elucidate mechanisms underlying the beneficial effects of physical fitness and acute exercise, behavioral and electrophysiological indices of Task preparation and response inhibition as a part of executive functions were assessed in a modified version of an Eriksen Flanker Task subsequent to an acute bout of aerobic exercise and a period of rest, respectively. 35 higher- and lower-fit adolescents between 13 and 14 years of age participated in a controlled cross-over study design. Results indicate that higher-fit individuals show significantly greater CNV amplitudes, reflecting enhanced Task preparation processes, as well as decreased amplitudes in N2, indexing more efficient executive control processes. P3 amplitudes associated with the allocation of attentional and memory control neither showed influences of physical fitness nor the acute bout of exercise. Furthermore, acute aerobic exercise was not related to any of the dependent measures. The current findings suggest that physical fitness, but not an acute bout of aerobic exercise enhances cognitive processing by increasing attentional allocation to stimulus encoding during Task preparation.