Trial Sequence Effects Research Articles

Semantic congruency modulates the speed-up of multisensory responses

Responses to multisensory signals are often faster compared to their unisensory components. This speed-up is typically attributed to target redundancy in that a correct response can be triggered by one or the other signal. In addition, semantic congruency of signals can also modulate multisensory responses; however, the contribution of semantic content is difficult to isolate as its manipulation commonly changes signal redundancy as well. To disentangle the effects of redundancy and semantic congruency, we manipulated semantic content but kept redundancy constant. We presented semantically congruent/incongruent animal pictures and sounds and asked participants to respond with the same response to two target animals (cats and dogs). We find that the speed-up of multisensory responses is larger for congruent (e.g., barking dogs) than incongruent combinations (e.g., barking cats). We then used a computational modelling approach to analyse audio-visual processing interferences that may underlie the effect. Our data is best described by a model that explains the semantic congruency modulation with a parameter that was previously linked to trial sequence effects, which in our experiment occur from the repetition/switching of both sensory modality and animal category. Yet, a systematic analysis of such trial sequence effects shows that the reported congruency effect is an independent phenomenon. Consequently, we discuss potential contributors to the semantic modulation of multisensory responses.

Memory load, distracter interference, and dynamic adjustments in cognitive control influence working memory performance across the lifespan.

Capacity-limited working memory (WM) systems have been known to degrade in older age. In line with inhibition-deficit theories of aging, WM deficits in older individuals have been attributed to failures in the ability to suppress the processing of task irrelevant, distracting information. Yet, other cognitive mechanisms underlying age-related WM deficits have been observed, including failures in WM with increasing memory load. Moreover, both distracting information and high memory load have been shown to trigger adjustments in cognitive control leading to subsequent performance benefits on later trials. However, no studies have characterized these dynamic adjustments across the life span or examined their contribution to WM deficits in older adults. We investigated the contribution of distracter interference, memory load, and dynamic adjustments in cognitive control on WM performance in 505 individuals with ages ranging from adolescence to older adulthood. Distracter interference and memory load were parametrically manipulated (high vs. low) in a delayed-recognition WM task, and accuracy was examined as a function of current (N) and previous (N-1) trial demands. Curvilinear models revealed that performance differs over the life span depending on specific WM task demands. Specifically, the ability to suppress task irrelevant distracters was greater in adulthood compared with adolescence, but worse in later life. In contrast, memory load resulted in performance deficits with increasing age, which were exacerbated when high load and interference demands combined. Dynamic adjustments in cognitive control was spared, in part, with memory-load triggered sequential trial effects maintained across the life span, but interference-triggered benefits observable up to middle age. (PsycInfo Database Record (c) 2020 APA, all rights reserved).

Associative priming and conflict differentially affect two processes underlying cognitive control: Evidence from reaching behavior.

Previous research has indicated that two components of reaching behavior, initiation time and reach curvature, exhibit distinct patterns of trial sequence effects in congruency tasks. The observed patterns have been proposed to reflect two dissociable processes underlying decision behavior, with initiation times capturing the functioning of a threshold adjustment process involving the temporary inhibition of motor output, and reach curvatures reflecting a controlled selection process that supports goal-driven stimulus-response translation. The tasks used in previous studies, however, did not control for a range of associative-priming confounds commonly featured in congruency tasks. Consequently, the extent to which the observed patterns reflected the proposed processes or associative-priming confounds remained unclear. We therefore presented 45 adult participants with a reach-tracking version of the Stroop task that featured both confound-minimized and confound-laden trials. Initiation times revealed main effects of previous and current congruency on both confound-minimized and confound-laden trials, consistent with the claim that initiation times can be used to target the functioning of the threshold adjustment process. Conversely, reach curvatures exhibited a clear sensitivity to associative-priming effects, revealing a congruency sequence effect on confound-laden but not on confound-minimized trials. This finding is consistent with the claim that reach curvatures can be used to target the functioning of the controlled selection process. Thus, by directly evaluating the influence of associative-priming confounds, the present study revealed the strongest evidence to date that decision behavior in tasks involving conflict is fundamentally structured by the functioning of two dissociable processes.

More evidence that a switch is not (always) a switch: Binning bilinguals reveals dissociations between task and language switching.

The current study examined the cognitive mechanisms underlying task and language switching by comparing them with each other, and with flanker task performance, at multiple points of the response time distribution. Ninety-eight Spanish-English bilinguals completed cued language and color-shape switching tasks, and 2 versions of a nonlinguistic flanker task. Bilinguals responded more quickly and exhibited smaller mixing costs in the language task, but surprisingly exhibited larger switching costs than in the color-shape task. This language-task disadvantage was especially apparent in slower reaction times (RTs), because switching costs increased significantly through the slowest end of the RT distribution only in the language task (but not in the color-shape task). Although the flanker task resembled the language task to a greater extent than the color-shape task in some measures (e.g., flanker effects were largest in the slowest RT bins, like language switching costs), in other measures the 2 switching tasks resembled each other and the flanker task stood out as different (i.e., trial sequence effects and correlations between tasks in various cost measures). These results reveal that different measures of switching costs even in tasks with very similar designs, vary in the extent to which they measure switching ability, both between tasks, and even between different trials within the same task. Distributional analysis of RTs across tasks suggests that slow responses, particularly when switching between non-naturally competing responses, might not measure switching ability at all, and raises the possibility that smaller switching costs can even reflect reduced ability to juggle tasks in some cases. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Deconstructing the Gratton effect: Targeting dissociable trial sequence effects in children, pre-adolescents, and adults

The Gratton effect refers to the observation that performance on congruency tasks is often enhanced when the congruency of the current trial matches that of the previous trial. This effect has been at the center of recent debates in the literature on cognitive control as researchers have sought to identify the cognitive and neural underpinnings of the effect. Here, we use a technique known as reach tracking to demonstrate that the Gratton effect originally observed in the flanker task is not a singular effect but the result of two separate trial sequence effects that impact dissociable processes underlying cognitive control. Further, our results indicate that these dissociable processes follow divergent developmental trajectories across childhood, pre-adolescence, and adulthood. Taken together, these findings suggest that manual dynamics can be used to disentangle how key processes underlying cognitive control contribute to the response time effects observed across a wide range of cognitive tasks and age groups.

Overriding actions in Parkinson’s disease: Impaired stopping and changing of motor responses.

We administered a stop-change paradigm, an extended version of the stop task that requires (a) stopping an ongoing motor response and (b) changing to an alternative (change) response. Performance of a group of patients diagnosed with Parkinson's disease (PD) and taking dopaminergic medication was compared with that of matched healthy control (HC) participants. Behavioral results indicated that response latencies to the initial go signal did not distinguish between the 2 groups, but that stopping latencies were prolonged in PD patients. In addition, the change response was delayed in the clinical group, indicating difficulties in flexibly changing to alternative motor actions upon external cues. The change deficit in PD related to the inhibition deficit. This dependence points to a serial processing architecture in PD according to which the stopping process has to finish before the change process can be initiated. In contrast, the HC group showed parallel stop and change processing. Analyses of sequential trial effects suggest that both HC and PD patients are susceptible to aftereffects of action override, due to the consequences of the automatic retrieval of recent associations between action and goal representations. Interestingly, postchange performance of the clinical group was hampered disproportionately, suggesting that PD is associated with an impairment in overriding previously formed action-goal associations. These findings support the notion that both higher-order cognitive control processes, such as inhibiting and changing actions, as well as lower-order feature binding mechanisms rely on basal ganglia functioning and are compromised by the basal ganglia dysfunction caused by PD. (PsycINFO Database Record

Inhibition in motor imagery: a novel action mode switching paradigm

Motor imagery requires that actual movements are prevented (i.e., inhibited) from execution. To investigate at what level inhibition takes place in motor imagery, we developed a novel action mode switching paradigm. Participants imagined (indicating only start and end) and executed movements from start buttons to target buttons, and we analyzed trial sequence effects. Trial sequences depended on current action mode (imagination or execution), previous action mode (pure blocks/same mode, mixed blocks/same mode, or mixed blocks/other mode), and movement sequence (action repetition, hand repetition, or hand alternation). Results provided evidence for global inhibition (indicated by switch benefits in execution-imagination (E-I)-sequences in comparison to I-I-sequences), effector-specific inhibition (indicated by hand repetition costs after an imagination trial), and target inhibition (indicated by target repetition benefits in I-I-sequences). No evidence for subthreshold motor activation or action-specific inhibition (inhibition of the movement of an effector to a specific target) was obtained. Two (global inhibition and effector-specific inhibition) of the three observed mechanisms are active inhibition mechanisms. In conclusion, motor imagery is not simply a weaker form of execution, which often is implied in views focusing on similarities between imagination and execution.

Neural correlates of and processes underlying generalized and differential return of fear.

Relapse represents a major limitation to long-term remission of psychopathology (anxiety, addiction). Relapse of anxiety can be modeled in the laboratory as return of fear (ROF) following un-signaled re-presentation of the aversive event (reinstatement, RI) after extinction. In humans, response enhancement to both the CS+ and CS- (generalized RI) or specifically to the CS+ (differential RI) has been described following RI. The (psychological) mechanisms and boundary conditions underlying these different RI qualities were investigated in 76 healthy participants using autonomic measures and functional magnetic resonance imaging. Our results suggest that both processes reflect distinct albeit intertwined (psychological) processes which are reflected in different neural activation patterns. Differential RI was linked to CS+ related hippocampal activation and CS- related disinhibition of the ventromedial prefrontal cortex (vmPFC). The latter likely contributes to robust generalized RI which was mirrored in thalamic and visual areas (as well as the bed nucleus of the striatum and inusula) possibly indicating generally facilitated salience processing. In addition, we also present data on experimental boundary conditions of RI (trial sequence effects, time stability). Taken together, this first comprehensive analysis of RI-induced ROF aids not only experimental research on ROF but also understanding of factors promoting clinical relapse and the role of the vmPFC.

Influence of Stimulus Type on Effects of Flanker, Flanker Position, and Trial Sequence in a Saccadic Eye Movement Task

Using the flanker paradigm in a task requiring eye movement responses, we examined how stimulus type (arrows vs. letters) modulated effects of flanker and flanker position. Further, we examined trial sequence effects and the impact of stimulus type on these effects. Participants responded to a central target with a left- or rightward saccade. We reasoned that arrows, being overlearned symbols of direction, are processed with less effort and are therefore linked more easily to a direction and a required response than are letters. The main findings demonstrate that (a) flanker effects were stronger for arrows than for letters, (b) flanker position more strongly modulated the flanker effect for letters than for arrows, and (c) trial sequence effects partly differed between the two stimulus types. We discuss these findings in the context of a more automatic and effortless processing of arrow relative to letter stimuli.

Can human autonomic classical conditioning occur without contingency awareness? The critical importance of the trial sequence

Most evidence suggests that awareness of the CS–US contingency is necessary for human autonomic conditioning. However, Schultz and Helmstetter (2010) reported unaware skin conductance conditioning using difficult-to-discriminate visual CSs. We sought to replicate these findings with procedures nearly identical to Schultz and Helmstetter among 66 participants. Results replicated the findings of significantly greater autonomic responding to CS+ than CS−; however, participants also demonstrated greater expectancy of shock to CS+ than CS− despite being classified as unaware. The differential expectancy and conditioning occurred only on trials that followed a CS+/CS− alternating sequence. On non-alternating trials, there was significantly higher expectancy and skin conductance responding to CS− compared to CS+. These results indicate that what initially appeared to be unaware differential conditioning was likely due to differential expectancy arising from a predictable trial sequence. These results underscore the critical importance of controlling for trial sequence effects in the study of learning.

Trial History Effects in Stroop Task Performance Are Independent of Top-Down Control

In this study we sought to elucidate what mechanisms underlie the effects of trial history on information processing. We explicitly focused on the contribution of conflict control and S-R binding to sequential trial effects. Performance and brain activity were measured during two hours of continuous Stroop task performance. Mental fatigue, known to influence top-down processing, was used to elucidate separate effects via top-down and bottom-up mechanisms. Here we confirm that performance in the Stroop task is indeed strongly modulated by stimulus history. Performance was affected by the kind of advance information available; dependent on this information adjustments were made, resulting in differential effects of cognitive conflict, and S-R binding on subsequent performance. The influence of mental fatigue on information processing was mainly related to general effects on attention.

Negative Emotion Does Not Modulate Rapid Feature Integration Effects

Emotional arousal at encoding is known to facilitate later memory recall. In the present study, we asked whether this emotion-modulation of episodic memory is also evident at very short time scales, as measured by “feature integration effects,” the moment-by-moment binding of relevant stimulus and response features in episodic memory. This question was motivated by recent findings that negative emotion appears to potentiate first-order trial sequence effects in classic conflict tasks, which has been attributed to emotion-modulation of conflict-driven cognitive control processes. However, these effects could equally well have been carried by emotion-modulation of mnemonic feature binding processes, which were perfectly confounded with putative control processes in these studies. In the present experiments, we tried to shed light on this question by testing explicitly whether feature integration processes, assessed in isolation of conflict–control, are in fact susceptible to negative emotion-modulation. For this purpose, we adopted a standard protocol for assessing the rapid binding of stimulus and response features in episodic memory (Experiment 1) and paired it with the presentation of either neutral or fearful background face stimuli, shown either at encoding only (Experiment 2), or at both encoding and retrieval (Experiment 3). Whereas reliable feature integration effects were observed in all three experiments, no evidence for emotion-modulation of these effects was detected, in spite of significant effects of emotion on response times. These findings suggest that rapid feature integration of foreground stimulus and response features is not subject to modulation by negative emotional background stimuli and further suggest that previous reports of emotion-modulated trial–transition effects are likely attributable to the effects of emotion on cognitive control processes.

Impaired visual decision-making in individuals with amblyopia

This study examined the effects of amblyopia on perceptual decision-making processes to determine the consequences of visual deprivation on the development of higher level cortical networks outside of the visual cortex. A variant of the Eriksen flanker task was used to measure response time and accuracy for decisions made in the presence of response-selection conflict. Performance of adults with amblyopia was compared to that of neurotypical participants of the same age. Additionally, simple and choice reaction time tasks presented in the visual and the auditory modality were used to control for factors such as feature visibility, crowding, and motor execution speed. A selective deficit in response time for visual decisions was found when individuals with amblyopia used either the amblyopic or non-amblyopic (dominant) eye, and this deficit was independent of visual acuity, motor time, and performance accuracy. In trial conditions that provoked response-selection conflict, responses were significantly delayed in amblyopic relative to neurotypical participants and were not subject to standard trial sequence effects. Our results indicate that, beyond the known effects of abnormal visual experience on visual cortex, suboptimal binocular input during a developmental critical period may also impact cortical connections to downstream areas of the brain, including parietal and frontal cortices, that are believed to underlie decision and response-selection processes.

Conflict adaptation and sequential trial effects: Support for the conflict monitoring theory

The purpose of this study was to investigate the cognitive control process of conflict adaptation and the recruitment of cognitive control across sequential trials-termed higher-order trial effects-using the N2 and P3 components of the scalp-recorded event-related potential (ERP). High-density ERPs were obtained from 181 healthy individuals (93 female, 88 male) during a modified Eriksen flanker task. Behavioral measures (i.e., error rates, reaction times [RTs]) and N2 and P3 amplitudes showed reliable conflict adaptation (i.e., previous-trial congruencies influenced current-trial measures). Higher-order trial effects were quantified across multiple sequential presentations of congruent or incongruent trials (e.g., four consecutive incongruent trials). For higher-order trial effects, P3 amplitudes and RTs reliably decreased across both congruent and incongruent trials. Consistent with the conflict monitoring theory, N2 amplitudes decreased across incongruent trials and increased across congruent trials. N2 amplitudes were positively correlated with incongruent-trial RTs; no significant correlations were found for P3 amplitudes and RTs. Effects remained when stimulus–response repetitions were removed. Results indicate that RTs and ERP measures are sensitive to modulations of cognitive control associated with conflict across multiple congruent and incongruent trials. Implications for the conflict monitoring theory of cognitive control are discussed.

Dynamic Coding of Events within the Inferior Frontal Gyrus in a Probabilistic Selective Attention Task

Besides the fact that RTs in cognitive tasks are affected by the specific demands of a trial, the context in which this trial occurs codetermines the speed of the response. For instance, invalid spatial cues generally prolong RTs to targets in the location-cueing paradigm, whereas the magnitude of these RT costs additionally varies as a function of the preceding trial types so that RTs for invalid trials may be increased when preceded by valid rather than invalid trials. In the present fMRI study, we investigated trial sequence effects in a combined oddball and location-cueing paradigm. In particular, we tested whether RTs and neural activity to infrequent invalid or deviant targets varied as a function of the number of preceding valid standard trials. As expected, RTs in invalid and deviant trials were significantly slower when more valid standard trials had been presented beforehand. This behavioral effect was reflected in the neural activity of the right inferior/middle frontal gyrus where the amplitude of the hemodynamic response in invalid and deviant trials was positively related to the number of preceding valid standard trials. In contrast, decreased activity (i.e., a negative parametric modulation effect) was observed when more valid standard trials were successively presented. Further positive parametric effects for the number of preceding valid standard trials were observed in the left caudate nucleus and lingual gyrus. The data suggest that inferior frontal cortex extracts both event regularities and irregularities in event streams.

Mechanisms underlying sequence effects in the stroop task

Event Abstract Back to Event Mechanisms underlying sequence effects in the stroop task Monicque Lorist1* 1 Department of Experimental Psychology, University of Groningen, Netherlands Not only congruency of the current trial affects performance in a Stroop task. Congruency of the preceding stimulus was found to modulate the processing of the current stimulus, as well. Sequential trial effects have been explained by top-down adjustments in cognitive control processes or by bottom-up associative priming mechanisms. In this study performance and related brain activity were measured during Stroop task performance in order to examine the contribution of conflict control elicited by incongruent colour and word meaning and the formation of stimulus–response associations to sequential trial effects. As expected, faster responses and lower error rates were observed in congruent Stroop trials compared to incongruent trials. Moreover, we confirmed that performance in the Stroop task is strongly modulated by stimulus history. These sequential trial effects were dependent on the stimulus features that were repeated. For example, congruency of the previous trial induced adjustments in information processing, except for trials in which the relevant stimulus feature (i.e. colour of the Stroop word) was repeated. In this condition a clear beneficial effect on performance efficiency was observed independent of congruency of the previous stimulus. Available models explaining sequence effects based on single stimulus features seem to fall short in explaining these effects. Performance seems to be modulated by the kind of information available; dependent on this information, top-down adjustments in cognitive control processes will be made and/or changes might be implemented via bottom-up mechanisms, resulting in differential effects of cognitive conflict and repetition priming on subsequent performance. Keywords: Attention, Stroop Conference: XI International Conference on Cognitive Neuroscience (ICON XI), Palma, Mallorca, Spain, 25 Sep - 29 Sep, 2011. Presentation Type: Poster Presentation Topic: Poster Sessions: Neurophysiology of Cognition and Attention Citation: Lorist M (2011). Mechanisms underlying sequence effects in the stroop task. Conference Abstract: XI International Conference on Cognitive Neuroscience (ICON XI). doi: 10.3389/conf.fnhum.2011.207.00317 Copyright: The abstracts in this collection have not been subject to any Frontiers peer review or checks, and are not endorsed by Frontiers. They are made available through the Frontiers publishing platform as a service to conference organizers and presenters. The copyright in the individual abstracts is owned by the author of each abstract or his/her employer unless otherwise stated. Each abstract, as well as the collection of abstracts, are published under a Creative Commons CC-BY 4.0 (attribution) licence (https://creativecommons.org/licenses/by/4.0/) and may thus be reproduced, translated, adapted and be the subject of derivative works provided the authors and Frontiers are attributed. For Frontiers’ terms and conditions please see https://www.frontiersin.org/legal/terms-and-conditions. Received: 22 Nov 2011; Published Online: 28 Nov 2011. * Correspondence: Dr. Monicque Lorist, Department of Experimental Psychology, University of Groningen, Groningen, Netherlands, m.m.lorist@rug.nl Login Required This action requires you to be registered with Frontiers and logged in. To register or login click here. Abstract Info Abstract The Authors in Frontiers Monicque Lorist Google Monicque Lorist Google Scholar Monicque Lorist PubMed Monicque Lorist Related Article in Frontiers Google Scholar PubMed Abstract Close Back to top Javascript is disabled. Please enable Javascript in your browser settings in order to see all the content on this page.

Conditional accuracy in response interference tasks: Evidence from the Eriksen flanker task and the spatial conflict task

Two well-known response interference tasks are the Eriksen flanker task and the spatial conflict task. The tasks are logically equivalent, and comparable effects of current and previous stimulus type (congruent or incongruent) have been shown with regard to reaction time (RT). Here, we investigated whether interference and sequential trial effects also had comparable effects on accuracy. We specifically tested whether these effects interacted with the speed of responding using conditional accuracy functions (CAFs). The CAFs revealed that in both tasks congruency and sequential trial effects on accuracy are found only in trials with fast responses (< 600 ms). Sequential trial effects on accuracy were weaker for the flanker task than for the spatial conflict task. In very fast trials (< 400 ms) response activation by distracting flankers led to below-chance performance in the flanker task, but response activation by incongruent spatial location did not lead to below-chance performance in the spatial conflict task. The pattern of results hints at subtle differences in processing architecture between the tasks.

Accounting for sequential trial effects in the flanker task: Conflict adaptation or associative priming?

The conflict-control loop theory proposes that the detection of conflict in information processing triggers an increase in cognitive control, resulting in improved performance on the subsequent trial. This theory seems consistent with the robust finding that conflict susceptibility is reduced following correct trials associated with high conflict: the conflict adaptation effect. However, despite providing favorable conditions for eliciting and detecting conflict-triggered performance adjustments, none of the five experiments reported here provide unequivocal evidence of such adjustments. Instead, the results corroborate and extend earlier findings by demonstrating that the conflict adaptation effect, at least in the flanker task, is only present for a specific subset of trial sequences that is characterized by a response repetition. This pattern of results provides strong evidence that the conflict adaptation effect reflects associative stimulus-response priming instead of conflict-driven adaptations in cognitive control.

Adjustments of Cognitive Control in Younger and Older Adults

The effects of aging on behavioral and electrophysiological indices of adjustments of cognitive control were examined in two experiments. Specifically, we considered the effects of aging of patterns of response time and modulations of the event-related brain potentials (ERPs) on sequential trial effects, error-related slowing, and local switch costs in two modified Stroop tasks. The behavioral data reveal that sequential trial effects were observed when color, but not word, identification was required and that these effects were similar in younger and older adults; that the degree of error-related slowing was similar for younger and older adults in Experiment 1 and greater in older than younger adults in Experiment 2; that local switch costs in response time were similar in younger and older adults and that the requirement to switch between color and word identification resulted in a dramatic increase in the number of color intrusion errors in older adults in Experiment 2. The ERP data revealed that endogenously generated adjustments of cognitive control were associated with a parietal slow wave that mirrored the behavioral data and was similar in amplitude in younger and older adults and an anterior frontal slow wave that was absent in older adults. The ERP data also revealed that an enhancement of the P3 component and a frontal slow wave that differentiated color switch trials from color non-switch and word trials in younger adults were attenuated in older adults.