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Beat Meier - One of the best experts on this subject based on the ideXlab platform.
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Age affects the adjustment of cognitive control after a conflict: evidence from the bivalency effect.
Neuropsychology development and cognition. Section B Aging neuropsychology and cognition, 2014Co-Authors: Alodie Rey-mermet, Beat MeierAbstract:Age affects cognitive control. When facing a conflict, older adults are less able to activate goal-relevant information and inhibit irrelevant information. However, cognitive control also affects the events after a conflict. The purpose of this study was to determine whether age affects the adjustment of cognitive control following a conflict. To this end, we investigated the bivalency effect, that is, the performance slowing occurring after the conflict induced by bivalent stimuli (i.e., stimuli with features for two tasks). In two experiments, we tested young adults (aged 20-30) and older adults (aged 65-85) in a paradigm requiring alternations between three tasks, with bivalent stimuli occasionally occurring on one task. The young adults showed a slowing for all trials following bivalent stimuli. This indicates a widespread and long-lasting bivalency effect, replicating previous findings. In contrast, the older adults showed a more specific and shorter-lived slowing. Thus, age affects the adjustment of cognitive control following a conflict.
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More conflict does not trigger more adjustment of cognitive control for subsequent events: a study of the bivalency effect.
Acta psychologica, 2013Co-Authors: Alodie Rey-mermet, Beat MeierAbstract:Encountering a conflict triggers an adjustment of cognitive control. This adjustment of cognitive control can even affect subsequent performance. The purpose of the present study was to determine whether more conflict triggers more adjustment of cognitive control for subsequent performance. To this end, we focussed on the bivalency effect, that is, the adjustment of cognitive control following the conflict induced by bivalent stimuli (i.e., stimuli with relevant features for two tasks). In two experiments, we tested whether the amount of conflict triggered by bivalent stimuli affected the bivalency effect. Bivalent stimuli were either compatible (i.e., affording one response) or incompatible (i.e., affording two different responses). Thus, compatible bivalent stimuli involved a task conflict, whereas incompatible bivalent stimuli involved a task and a response conflict. The results showed that the bivalency effect was not affected by this manipulation. This indicates that more conflict does not trigger more adjustment of cognitive control for subsequent performance. Therefore, only the occurrence of conflict--not its amount--is determinant for cognitive control.
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An orienting response is not enough: Bivalency not infrequency causes the bivalency effect
Advances in Cognitive Psychology, 2013Co-Authors: Alodie Rey-mermet, Beat MeierAbstract:When switching tasks, occasionally responding to bivalent stimuli (i.e., stimuli with relevant features for two different tasks) slows performance on subsequent univalent stimuli, even when they do not share relevant features with bivalent stimuli. This performance slowing is labelled the bivalency effect here, we investigated whether the bivalency effect results from an orienting response to the infrequent stimuli (i.e., the bivalent stimuli). To this end, we compared the impact of responding to infrequent univalent stimuli to the impact of responding to infrequent bivalent stimuli. For the latter, the results showed a performance slowing for all trials following bivalent stimuli. This indicates a long-lasting bivalency effect, replicating previous findings. For infrequent univalent stimuli, however, the results showed a smaller and shorter-lived performance slowing. These results demonstrate that the bivalency effect does not simply reflect an orienting response to infrequent stimuli. Rather it results from the conflict induced by bivalent stimuli, probably by episodic binding with the more demanding context created by them
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The bivalency effect represents an interference-triggered adjustment of cognitive control: an ERP study.
Cognitive affective & behavioral neuroscience, 2013Co-Authors: Alodie Rey-mermet, Thomas Koenig, Beat MeierAbstract:When bivalent stimuli (i.e., stimuli with relevant features for two different tasks) occur occasionally among univalent stimuli, performance is slowed on subsequent univalent stimuli even if they have no overlapping stimulus features. This finding has been labeled the bivalency effect. It indexes an adjustment of cognitive control, but the underlying mechanism is not well understood yet. The purpose of the present study was to shed light on this question, using event-related potentials. We used a paradigm requiring predictable alternations between three tasks, with bivalent stimuli occasionally occurring on one task. The results revealed that the bivalency effect elicited a sustained parietal positivity and a frontal negativity, a neural signature that is typical for control processes implemented to resolve interference. We suggest that the bivalency effect reflects interference, which may be caused by episodic context binding.
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Episodic context binding in task switching: Evidence from amnesia
Neuropsychologia, 2013Co-Authors: Beat Meier, Alodie Rey-mermet, Todd S. Woodward, René M. Müri, Klemens GutbrodAbstract:The purpose of the present study was to investigate whether amnesic patients show a bivalency effect. The bivalency effect refers to the performance slowing that occurs when switching tasks and bivalent stimuli appear occasionally among univalent stimuli. According to the episodic context binding account, bivalent stimuli create a conflict-loaded context that is re-activated on subsequent trials and thus it is assumed that it depends on memory binding processes. Given the profound memory deficit in amnesia, we hypothesized that the bivalency effect would be largely reduced in amnesic patients. We tested sixteen severely amnesic patients and a control group with a paradigm requiring predictable alternations between three simple cognitive tasks, with bivalent stimuli occasionally occurring on one of these tasks. The results showed the typical bivalency effect for the control group, that is, a generalized slowing for each task. In contrast, for amnesic patients, only a short-lived slowing was present on the task that followed immediately after a bivalent stimulus, indicating that the binding between tasks and context was impaired in amnesic patients.
Judith M. Shedden - One of the best experts on this subject based on the ideXlab platform.
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Support for a history-dependent predictive model of dACC activity in producing the bivalency effect: an event-related potential study.
Neuropsychologia, 2014Co-Authors: John G. Grundy, Judith M. SheddenAbstract:Abstract In the present study, we examine electrophysiological correlates of factors influencing an adjustment in cognitive control known as the bivalency effect. During task-switching, the occasional presence of bivalent stimuli in a block of univalent trials is enough to elicit a response slowing on all subsequent univalent trials. Bivalent stimuli can be congruent or incongruent with respect to the response afforded by the irrelevant stimulus feature. Here we show that the incongruent bivalency effect, the congruent bivalency effect, and an effect of a simple violation of expectancy are captured at a frontal ERP component (between 300 and 550 ms) associated with ACC activity, and that the unexpectedness effect is distinguished from both congruent and incongruent bivalency effects at an earlier component (100–120 ms) associated with the temporal parietal junction. We suggest that the frontal component reflects the dACC’s role in predicting future cognitive load based on recent history. In contrast, the posterior component may index early visual feature extraction in response to bivalent stimuli that cue currently ongoing tasks; dACC activity may trigger the temporal parietal activity only when specific task cueing is involved and not for simple violations of expectancy.
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A role for recency of response conflict in producing the bivalency effect.
Psychological research, 2013Co-Authors: John G. Grundy, Judith M. SheddenAbstract:The bivalency effect is a block-wise response slowing that is observed during task-switching when rare stimuli that cue two tasks (bivalent stimuli) are encountered. This adjustment in response style affects all trials that follow bivalent stimuli, including those trials that do not share any features with bivalent stimuli. However, the specific stimulus and response properties that trigger the bivalency effect are not well understood. In typical bivalency effect experiments, bivalent stimuli can be congruent or incongruent with respect to the response afforded by the irrelevant stimulus feature, and this distinction has never been examined. In the present study, we show that cognitive load defined by the response incongruence on bivalent trials plays a critical role in producing the subsequent response slowing observed in the bivalency effect, as well as maintaining the magnitude of the bivalency effect across practice. We propose that the bivalency effect reflects a process involved in predicting future cognitive load based on recent cognitive load experience. This is in line with a recent proposal for a role of the ACC in monitoring ongoing changes in the environment to optimize future performance (Sheth et al., in Nature 488:218–221, 2012).
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The Bivalency effect in task switching: Event-related potentials
Human brain mapping, 2011Co-Authors: John G. Grundy, Todd S. Woodward, Miriam F.f. Benarroch, Paul D. Metzak, Jennifer C. Whitman, Judith M. SheddenAbstract:During task switching, if we occasionally encounter stimuli that cue more than one task (i.e., bivalent stimuli), response slowing is observed on all univalent trials within that block, even when no features overlap with the bivalent stimuli. This observation is known as the bivalency effect. Previous fMRI work (Woodward et al., 2008) clearly suggests a role for the dorsal anterior cingulate cortex (dACC) in the bivalency effect, but the time course remains uncertain. Here, we present the first high-temporal resolution account for the bivalency effect using stimulus-locked event-related potentials. Participants alternated among three simple tasks in six experimental blocks, with bivalent stimuli appearing occasionally in bivalent blocks (blocks 2, 4, and 6). The increased reaction times for univalent stimuli in bivalent blocks demonstrate that these stimuli are being processed differently from univalent stimuli in purely univalent blocks. Frontal electrode sites captured significant amplitude differences associated with the bivalency effect within time windows 100–120 ms, 375–450 ms, and 500–550 ms, which may reflect additional extraction of visual features present in bivalent stimuli (100–120 ms) and suppression of processing carried over from irrelevant cues (375–450 ms and 500–550 ms). Our results support the fMRI findings and provide additional evidence for involvement of the dACC. Furthermore, the bivalency effect dissipated with extended practice both behaviorally and electrophysiologically. These findings are discussed in relation to the differential processing involved in a controlled response style. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.
Alodie Rey-mermet - One of the best experts on this subject based on the ideXlab platform.
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Age affects the adjustment of cognitive control after a conflict: evidence from the bivalency effect.
Neuropsychology development and cognition. Section B Aging neuropsychology and cognition, 2014Co-Authors: Alodie Rey-mermet, Beat MeierAbstract:Age affects cognitive control. When facing a conflict, older adults are less able to activate goal-relevant information and inhibit irrelevant information. However, cognitive control also affects the events after a conflict. The purpose of this study was to determine whether age affects the adjustment of cognitive control following a conflict. To this end, we investigated the bivalency effect, that is, the performance slowing occurring after the conflict induced by bivalent stimuli (i.e., stimuli with features for two tasks). In two experiments, we tested young adults (aged 20-30) and older adults (aged 65-85) in a paradigm requiring alternations between three tasks, with bivalent stimuli occasionally occurring on one task. The young adults showed a slowing for all trials following bivalent stimuli. This indicates a widespread and long-lasting bivalency effect, replicating previous findings. In contrast, the older adults showed a more specific and shorter-lived slowing. Thus, age affects the adjustment of cognitive control following a conflict.
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More conflict does not trigger more adjustment of cognitive control for subsequent events: a study of the bivalency effect.
Acta psychologica, 2013Co-Authors: Alodie Rey-mermet, Beat MeierAbstract:Encountering a conflict triggers an adjustment of cognitive control. This adjustment of cognitive control can even affect subsequent performance. The purpose of the present study was to determine whether more conflict triggers more adjustment of cognitive control for subsequent performance. To this end, we focussed on the bivalency effect, that is, the adjustment of cognitive control following the conflict induced by bivalent stimuli (i.e., stimuli with relevant features for two tasks). In two experiments, we tested whether the amount of conflict triggered by bivalent stimuli affected the bivalency effect. Bivalent stimuli were either compatible (i.e., affording one response) or incompatible (i.e., affording two different responses). Thus, compatible bivalent stimuli involved a task conflict, whereas incompatible bivalent stimuli involved a task and a response conflict. The results showed that the bivalency effect was not affected by this manipulation. This indicates that more conflict does not trigger more adjustment of cognitive control for subsequent performance. Therefore, only the occurrence of conflict--not its amount--is determinant for cognitive control.
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An orienting response is not enough: Bivalency not infrequency causes the bivalency effect
Advances in Cognitive Psychology, 2013Co-Authors: Alodie Rey-mermet, Beat MeierAbstract:When switching tasks, occasionally responding to bivalent stimuli (i.e., stimuli with relevant features for two different tasks) slows performance on subsequent univalent stimuli, even when they do not share relevant features with bivalent stimuli. This performance slowing is labelled the bivalency effect here, we investigated whether the bivalency effect results from an orienting response to the infrequent stimuli (i.e., the bivalent stimuli). To this end, we compared the impact of responding to infrequent univalent stimuli to the impact of responding to infrequent bivalent stimuli. For the latter, the results showed a performance slowing for all trials following bivalent stimuli. This indicates a long-lasting bivalency effect, replicating previous findings. For infrequent univalent stimuli, however, the results showed a smaller and shorter-lived performance slowing. These results demonstrate that the bivalency effect does not simply reflect an orienting response to infrequent stimuli. Rather it results from the conflict induced by bivalent stimuli, probably by episodic binding with the more demanding context created by them
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The bivalency effect represents an interference-triggered adjustment of cognitive control: an ERP study.
Cognitive affective & behavioral neuroscience, 2013Co-Authors: Alodie Rey-mermet, Thomas Koenig, Beat MeierAbstract:When bivalent stimuli (i.e., stimuli with relevant features for two different tasks) occur occasionally among univalent stimuli, performance is slowed on subsequent univalent stimuli even if they have no overlapping stimulus features. This finding has been labeled the bivalency effect. It indexes an adjustment of cognitive control, but the underlying mechanism is not well understood yet. The purpose of the present study was to shed light on this question, using event-related potentials. We used a paradigm requiring predictable alternations between three tasks, with bivalent stimuli occasionally occurring on one task. The results revealed that the bivalency effect elicited a sustained parietal positivity and a frontal negativity, a neural signature that is typical for control processes implemented to resolve interference. We suggest that the bivalency effect reflects interference, which may be caused by episodic context binding.
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Episodic context binding in task switching: Evidence from amnesia
Neuropsychologia, 2013Co-Authors: Beat Meier, Alodie Rey-mermet, Todd S. Woodward, René M. Müri, Klemens GutbrodAbstract:The purpose of the present study was to investigate whether amnesic patients show a bivalency effect. The bivalency effect refers to the performance slowing that occurs when switching tasks and bivalent stimuli appear occasionally among univalent stimuli. According to the episodic context binding account, bivalent stimuli create a conflict-loaded context that is re-activated on subsequent trials and thus it is assumed that it depends on memory binding processes. Given the profound memory deficit in amnesia, we hypothesized that the bivalency effect would be largely reduced in amnesic patients. We tested sixteen severely amnesic patients and a control group with a paradigm requiring predictable alternations between three simple cognitive tasks, with bivalent stimuli occasionally occurring on one of these tasks. The results showed the typical bivalency effect for the control group, that is, a generalized slowing for each task. In contrast, for amnesic patients, only a short-lived slowing was present on the task that followed immediately after a bivalent stimulus, indicating that the binding between tasks and context was impaired in amnesic patients.
Todd S. Woodward - One of the best experts on this subject based on the ideXlab platform.
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Episodic context binding in task switching: Evidence from amnesia
Neuropsychologia, 2013Co-Authors: Beat Meier, Alodie Rey-mermet, Todd S. Woodward, René M. Müri, Klemens GutbrodAbstract:The purpose of the present study was to investigate whether amnesic patients show a bivalency effect. The bivalency effect refers to the performance slowing that occurs when switching tasks and bivalent stimuli appear occasionally among univalent stimuli. According to the episodic context binding account, bivalent stimuli create a conflict-loaded context that is re-activated on subsequent trials and thus it is assumed that it depends on memory binding processes. Given the profound memory deficit in amnesia, we hypothesized that the bivalency effect would be largely reduced in amnesic patients. We tested sixteen severely amnesic patients and a control group with a paradigm requiring predictable alternations between three simple cognitive tasks, with bivalent stimuli occasionally occurring on one of these tasks. The results showed the typical bivalency effect for the control group, that is, a generalized slowing for each task. In contrast, for amnesic patients, only a short-lived slowing was present on the task that followed immediately after a bivalent stimulus, indicating that the binding between tasks and context was impaired in amnesic patients.
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More than a surprise: The bivalency effect in task switching
Journal of Cognitive Psychology, 2013Co-Authors: Paul D. Metzak, Beat Meier, Peter Graf, Todd S. WoodwardAbstract:When switching tasks, if stimuli are presented that contain features that cue two of the tasks in the set (i.e., bivalent stimuli), performance slowing is observed on all tasks. This generalized slowing extends to tasks in the set which have no features in common with the bivalent stimulus and is referred to as the bivalency effect. In previous work, the bivalency effect was invoked by presenting occasionally occurring bivalent stimuli; therefore, the possibility that the generalized slowing is simply due to surprise (as opposed to bivalency) has not yet been discounted. This question was addressed in two task switching experiments where the occasionally occurring stimuli were either bivalent (bivalent version) or merely surprising (surprising version). The results confirmed that the generalized slowing was much greater in the bivalent version of both experiments, demonstrating that the magnitude of this effect is greater than can be accounted for by simple surprise. This set of results confirms that slowing task execution when encountering bivalent stimuli may be fundamental for efficient task switching, as adaptive tuning of response style may serve to prepare the cognitive system for possible future high conflict trials.
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The Bivalency effect in task switching: Event-related potentials
Human brain mapping, 2011Co-Authors: John G. Grundy, Todd S. Woodward, Miriam F.f. Benarroch, Paul D. Metzak, Jennifer C. Whitman, Judith M. SheddenAbstract:During task switching, if we occasionally encounter stimuli that cue more than one task (i.e., bivalent stimuli), response slowing is observed on all univalent trials within that block, even when no features overlap with the bivalent stimuli. This observation is known as the bivalency effect. Previous fMRI work (Woodward et al., 2008) clearly suggests a role for the dorsal anterior cingulate cortex (dACC) in the bivalency effect, but the time course remains uncertain. Here, we present the first high-temporal resolution account for the bivalency effect using stimulus-locked event-related potentials. Participants alternated among three simple tasks in six experimental blocks, with bivalent stimuli appearing occasionally in bivalent blocks (blocks 2, 4, and 6). The increased reaction times for univalent stimuli in bivalent blocks demonstrate that these stimuli are being processed differently from univalent stimuli in purely univalent blocks. Frontal electrode sites captured significant amplitude differences associated with the bivalency effect within time windows 100–120 ms, 375–450 ms, and 500–550 ms, which may reflect additional extraction of visual features present in bivalent stimuli (100–120 ms) and suppression of processing carried over from irrelevant cues (375–450 ms and 500–550 ms). Our results support the fMRI findings and provide additional evidence for involvement of the dACC. Furthermore, the bivalency effect dissipated with extended practice both behaviorally and electrophysiologically. These findings are discussed in relation to the differential processing involved in a controlled response style. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.
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The bivalency effect in task switching: general and enduring.
Canadian journal of experimental psychology = Revue canadienne de psychologie experimentale, 2009Co-Authors: Beat Meier, Alodie Rey-mermet, Todd S. Woodward, Peter GrafAbstract:The purpose of this study was to investigate the generality and temporal endurance of the bivalency effect in task switching. This effect refers to the slowing on univalent stimuli that occurs when bivalent stimuli appear occasionally. We used a paradigm involving predictable switches between 3 simple tasks, with bivalent stimuli occasionally occurring on one of the tasks. The generality of the bivalency effect was investigated by using different tasks and different types of bivalent stimuli, and the endurance of this effect was investigated across different intertrial intervals (ITIs) and across the univalent trials that followed trials with bivalent stimuli. In 3 experiments, the results showed a general, robust, and enduring bivalency effect for all ITI conditions. Although the effect declined across trials, it remained significant for about 4 trials following one with a bivalent stimulus. Our findings emphasise the importance of top–down processes in task-switching performance.
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Anterior cingulate cortex signals the requirement to break inertia when switching tasks: a study of the bivalency effect.
NeuroImage, 2008Co-Authors: Todd S. Woodward, Beat Meier, Paul D. Metzak, Clay B. HolroydAbstract:When switching tasks, if stimuli are presented that cue two of the tasks in the task set (i.e., bivalent stimuli), performance slowing is observed on all tasks, including those not cued by the bivalent stimulus. This slowing has been coined the bivalency effect, and may reflect adaptive tuning of the response style under conditions that appear to require adjustments in control over the course of action. Recent work on the function of the dorsal anterior cingulate (dACC) cortex has suggested that this neural region may be recruited under such conditions. In the current task switching study, we used tightly matched experimental and control conditions to isolate the bivalency effect. As predicted, dACC activation was associated with the bivalency effect, supporting an account stating that the role of the dACC is to signal a break in task inertia in order to adaptively tune the response style due to conditions that may require adjustments in control over the course of action. This result may extend the conflict monitoring account of dACC activation to situations where conflict occurred on past trials (i.e., conflict is not elicited by the current stimulus), and/or may support a more generalized account of dACC function involving monitoring internal states for conditions that may require adjustments in control over the course of action.
John G. Grundy - One of the best experts on this subject based on the ideXlab platform.
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Support for a history-dependent predictive model of dACC activity in producing the bivalency effect: an event-related potential study.
Neuropsychologia, 2014Co-Authors: John G. Grundy, Judith M. SheddenAbstract:Abstract In the present study, we examine electrophysiological correlates of factors influencing an adjustment in cognitive control known as the bivalency effect. During task-switching, the occasional presence of bivalent stimuli in a block of univalent trials is enough to elicit a response slowing on all subsequent univalent trials. Bivalent stimuli can be congruent or incongruent with respect to the response afforded by the irrelevant stimulus feature. Here we show that the incongruent bivalency effect, the congruent bivalency effect, and an effect of a simple violation of expectancy are captured at a frontal ERP component (between 300 and 550 ms) associated with ACC activity, and that the unexpectedness effect is distinguished from both congruent and incongruent bivalency effects at an earlier component (100–120 ms) associated with the temporal parietal junction. We suggest that the frontal component reflects the dACC’s role in predicting future cognitive load based on recent history. In contrast, the posterior component may index early visual feature extraction in response to bivalent stimuli that cue currently ongoing tasks; dACC activity may trigger the temporal parietal activity only when specific task cueing is involved and not for simple violations of expectancy.
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A role for recency of response conflict in producing the bivalency effect.
Psychological research, 2013Co-Authors: John G. Grundy, Judith M. SheddenAbstract:The bivalency effect is a block-wise response slowing that is observed during task-switching when rare stimuli that cue two tasks (bivalent stimuli) are encountered. This adjustment in response style affects all trials that follow bivalent stimuli, including those trials that do not share any features with bivalent stimuli. However, the specific stimulus and response properties that trigger the bivalency effect are not well understood. In typical bivalency effect experiments, bivalent stimuli can be congruent or incongruent with respect to the response afforded by the irrelevant stimulus feature, and this distinction has never been examined. In the present study, we show that cognitive load defined by the response incongruence on bivalent trials plays a critical role in producing the subsequent response slowing observed in the bivalency effect, as well as maintaining the magnitude of the bivalency effect across practice. We propose that the bivalency effect reflects a process involved in predicting future cognitive load based on recent cognitive load experience. This is in line with a recent proposal for a role of the ACC in monitoring ongoing changes in the environment to optimize future performance (Sheth et al., in Nature 488:218–221, 2012).
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The Bivalency effect in task switching: Event-related potentials
Human brain mapping, 2011Co-Authors: John G. Grundy, Todd S. Woodward, Miriam F.f. Benarroch, Paul D. Metzak, Jennifer C. Whitman, Judith M. SheddenAbstract:During task switching, if we occasionally encounter stimuli that cue more than one task (i.e., bivalent stimuli), response slowing is observed on all univalent trials within that block, even when no features overlap with the bivalent stimuli. This observation is known as the bivalency effect. Previous fMRI work (Woodward et al., 2008) clearly suggests a role for the dorsal anterior cingulate cortex (dACC) in the bivalency effect, but the time course remains uncertain. Here, we present the first high-temporal resolution account for the bivalency effect using stimulus-locked event-related potentials. Participants alternated among three simple tasks in six experimental blocks, with bivalent stimuli appearing occasionally in bivalent blocks (blocks 2, 4, and 6). The increased reaction times for univalent stimuli in bivalent blocks demonstrate that these stimuli are being processed differently from univalent stimuli in purely univalent blocks. Frontal electrode sites captured significant amplitude differences associated with the bivalency effect within time windows 100–120 ms, 375–450 ms, and 500–550 ms, which may reflect additional extraction of visual features present in bivalent stimuli (100–120 ms) and suppression of processing carried over from irrelevant cues (375–450 ms and 500–550 ms). Our results support the fMRI findings and provide additional evidence for involvement of the dACC. Furthermore, the bivalency effect dissipated with extended practice both behaviorally and electrophysiologically. These findings are discussed in relation to the differential processing involved in a controlled response style. Hum Brain Mapp, 2013. © 2011 Wiley Periodicals, Inc.