Response-stimulus Interval Research Articles

Sleep Disruption Impairs Sustained Attention in Food-Restricted Rats Using a Food-Reinforced Rodent Psychomotor Vigilance Test.

Sleep disruption (SD) impairs sustained attention, and impairment is quantified with the psychomotor vigilance test (PVT) in humans. In rats, food restriction attenuates SD's effects on sustained attention, limiting translation of rodent vigilance tests. The goal of the current study was to determine if a rodent PVT (rPVT) requiring high baseline performance using food restriction and reinforcement is sensitive to the effects of SD. Male Long-Evans rats (n=4) were trained on the rPVT using food reinforcement. Once baseline acquisition criteria were achieved, rats experienced acute SD using an automated sweep bar that moved across the home cage. Rats were tested in the rPVT the day following SD to assess performance-impairing effects. SD significantly increased lapses, and this effect was specific to shorter response-stimulus intervals. Decreased percent correct responses and increased slow reaction times were also found. These data suggest that many of the performance-impairing effects of SD are not attenuated by food restriction in this procedure. The rPVT is sensitive to the performance impairing effects of SD in food restricted rats, a common methodology used to train and maintain performance on operant behavioral tests. Thus, food restriction does not appear to attenuate the effects of SD in all attention-related behavioral procedures.

Task-general or specific: The alertness modulates post-error adjustment

Previous studies have shown that alertness is closely related to executive control function, but its impact on components of post-error adjustment is unknown. This study applied the Attentional Networks Test and the Four-choice Flanker task with three response stimulus intervals (RSIs) to explore the correlation between alertness and post-error adjustment. The linear mixed-effects model of alertness and RSI on the post-error processing indicators showed a significant negative correlation between the alertness and post-error slowing (PES) under 200 ms RSI , as well as between alertness and post-error improvement in accuracy (PIA) under both 700 ms RSI and 1200 ms RSI. Participants with lower alertness showed larger post-error slowing in the early stages, while those with higher alertness had smaller PIA in later stages. This study revealed the effects of alertness on different processing components of post-error adjustment. The control strategies utilized by individuals with high and low levels of alertness differed in preparation for performance monitoring. Alertness improved post-error response speed in a task-unspecific manner, but not post-error adaptation.

Modality-general and modality-specific bilingual control mechanisms in spoken and written productions

Abstract Do bilinguals have similar bilingual control mechanisms in speaking and writing? The present study investigated the patterns of switch costs (reflecting reactive language control) and mixing costs (reflecting proactive language control) between Chinese (L1) and English (L2) in spoken and written productions and whether these patterns could be modulated by response-stimulus intervals (RSIs). In two experiments, unbalanced Chinese–English bilinguals completed a cued language switching task in spoken naming (Experiment 1) and written naming (Experiment 2), respectively. The results revealed asymmetrical switch costs (i.e., the larger cost in L1 than in L2) in spoken and written productions in the short RSI condition. However, there were asymmetrical mixing costs in spoken production and symmetrical mixing costs in written production both in the short and long RSIs. These findings suggest that for spoken and written productions, reactive language control operates in similar mechanisms, while proactive language control operates in specific mechanisms.

Voluntary task switching is affected by modality compatibility and preparation

Cognitive task control can be examined in task-switching studies. Performance costs in task switches are usually smaller with compatible stimulus-response modality mappings (visual-manual and auditory-vocal) than with incompatible mappings (visual-vocal and auditory-manual). Modality compatibility describes the modality match of sensory input and of the anticipated response effect (e.g., vocal responses produce auditory effects, so that auditory stimuli are modality-compatible with vocal responses). Fintor et al. (Psychological Research, 84(2), 380–388, 2020) found that modality compatibility also biased task choice rates in voluntary task switching (VTS). In that study, in each trial participants were presented with a visual or auditory spatial stimulus and were free to choose the response modality (manual vs. vocal). In this free-choice task, participants showed a bias to create more modality-compatible than -incompatible mappings. In the present study, we assessed the generality of Fintor et al.’s (2020) findings, using verbal rather than spatial stimuli, and more complex tasks, featuring an increased number of stimulus-response alternatives. Experiment 1 replicated the task-choice bias to preferentially create modality-compatible mappings. We also found a bias to repeat the response modality just performed, and a bias to repeat entire stimulus-response modality mappings. In Experiment 2, we manipulated the response-stimulus interval (RSI) to examine whether more time for proactive cognitive control would help resolve modality-specific crosstalk in this free-choice paradigm. Long RSIs led to a decreased response-modality repetition bias and mapping repetition bias, but the modality-compatibility bias was unaffected. Together, the findings suggest that modality-specific priming of response modality influences task choice.

Early Action Error Processing Is Due to Domain-General Surprise, Whereas Later Processing Is Error Specific.

The ability to adapt behavior after erroneous actions is one of the key aspects of cognitive control. Error commission typically causes people to slow down their subsequent actions [post-error slowing (PES)]. Recent work has challenged the notion that PES reflects adaptive, controlled processing and instead suggests that it is a side effect of the surprising nature of errors. Indeed, human neuroimaging suggests that the brain networks involved in processing errors overlap with those processing error-unrelated surprise, calling into question whether there is a specific system for error processing in the brain at all. In the current study, we used EEG decoding and a novel behavioral paradigm to test whether there are indeed unique, error-specific processes that contribute to PES beyond domain-general surprise. Across two experiments in male and female humans (N = 76), we found that both errors and error-unrelated surprise were followed by slower responses when response-stimulus intervals were short. Furthermore, the early neural processes following error-specific and domain-general surprise showed significant cross-decoding. However, at longer intervals, which provided additional processing time, only errors were still followed by post-trial slowing. Furthermore, this error-specific PES effect was reflected in sustained neural activity that could be decoded from that associated with domain-general surprise, with the strongest contributions found at lateral frontal, occipital, and sensorimotor scalp sites. These findings suggest that errors and surprise initially share common processes, but that after additional processing time, unique, genuinely error-specific processes take over and contribute to behavioral adaptation.SIGNIFICANCE STATEMENT Humans typically slow their actions after errors (PES). Some suggest that PES is a side effect of the unexpected, surprising nature of errors, challenging the notion of a genuine error processing system in the human brain. Here, we used multivariate EEG decoding to identify behavioral and neural processes uniquely related to error processing. Action slowing occurred following both action errors and error-unrelated surprise when time to prepare the next response was short. However, when there was more time to react, only errors were followed by slowing, further reflected in sustained neural activity. This suggests that errors and surprise initially share common processing, but that after additional time, error-specific, adaptive processes take over.

Repeating head fakes in basketball: Temporal aspects affect the congruency sequence effect and the size of the head-fake effect.

The head fake in basketball is used to hinder the anticipation performance of an opponent. During a head fake, a player turns the head into one direction, but passes the ball to the opposite direction. Several studies showed that responses to the pass direction are slower when a basketball player applies a head fake, which is known as the head-fake effect. While this effect in general is very robust, some studies showed a modulation by the trial sequence, signified by a reduced or eliminated effect when two head fakes are performed in succession. The present study examined the question how this so-called congruency sequence effect (CSE) is influenced by different timings. To this end, the interval between the response to the previous target and the onset of the next target (response-stimulus interval [RSI]; Experiment 1) and the interval between two targets (interstimulus interval [ISI]; Experiment 2) were manipulated. Results revealed a CSE for the short ISI (500 ms), and even a reversed effect for the short RSI (500 ms). Interestingly, the intermediate (2,000 ms) and long (5,000 ms) ISIs and RSIs did not show a CSE, but also no head-fake effect. Results are discussed regarding practical demands and theoretical implications. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Paradoxical effects from stimulus density manipulation provide new insight into the impact of sleep deprivation on PVT performance.

The psychomotor vigilance test (PVT), a 10-min one-choice reaction time task with random response-stimulus intervals (RSIs) between 2 and 10 s, is highly sensitive to behavioral alertness deficits due to sleep loss. To investigate what drives the performance deficits, we conducted an in-laboratory total sleep deprivation (TSD) study and compared performance on the PVT to performance on a 10-min high-density PVT (HD-PVT) with increased stimulus density and truncated RSI range between 2 and 5 s. We hypothesized that the HD-PVT would show greater impairments from TSD than the standard PVT. n = 86 healthy adults were randomized (2:1 ratio) to 38 h of TSD (n = 56) or corresponding well-rested control (n = 30). The HD-PVT was administered when subjects had been awake for 34 h (TSD group) or 10 h (control group). Performance on the HD-PVT was compared to performance on the standard PVTs administered 1 h earlier and 1 h later. The HD-PVT yielded approximately 60% more trials than the standard PVT. The HD-PVT had faster mean response times (RTs) and equivalent lapses (RTs > 500 ms) compared to the standard PVT, with no differences between the TSD effects on mean RT and lapses between tasks. Further, the HD-PVT had a dampened time-on-task effect in both the TSD and control conditions. Contrary to expectation, the HD-PVT did not show greater performance impairment during TSD, indicating that stimulus density and RSI range are not primary drivers of the PVT's responsiveness to sleep loss.

Stress-induced impairment reveals the stage and features of post-error adaptive adjustment.

An increased reaction time often occurs after error responses (post-error slowing, PES). However, the role of top-down regulation in post-error processing remains to be debated. Impairing cognitive control function through acute stress would help to investigate the role and stage of top-down adaptive regulation in post-error processing. Here, we recruited 50 healthy male participants who were randomly assigned to either a stress condition (Trier Social Stress Task, TSST) or a control condition (control version of the TSST). A color-word Stroop task with different response stimulus intervals (RSIs) was used to investigate the effects of acute stress on different stages of post-error processing. The results showed that cortisol, heart rate, perceived stress level, and negative affect were higher in the stress group (n = 24) than in the control group (n = 26), indicating successful stress induction. The accuracy of post-error response in the control group increased with the extension of RSI, and the reaction time decreased. However, the accuracy of 1,200 ms RSI was close to that of 700 ms RSI in the stress group but was significantly lower than that in the control group. The results suggested that acute stress caused the impairment of top-down adaptive regulation after error. Furthermore, our study manifested adaptive adjustment only in the late stages of post-error processing, indicating the phasic and adaptive features of post-error adjustment.

Language switching in different contexts and modalities: Response-stimulus interval influences cued-naming but not voluntary-naming or comprehension language-switching costs

AbstractLanguage switching is often associated with language competition and switching costs. However, the underlying mechanisms might differ depending on context (free versus cued naming) and modality (production or comprehension). In this study, we assessed how response-stimulus intervals (RSI) influence language-switching costs. Longer RSIs might provide more time for interference from the previous trial to decay and result in smaller switching costs. Mandarin–English bilinguals completed two dual-language production tasks (Experiment 1: cued and voluntary picture naming) and one comprehension task (Experiment 2: animacy judgement) with a short RSI and a long RSI condition. While switching costs were present in all tasks, they were only influenced by RSI length in the cued-production task, with smaller switching costs in the long RSI condition. In contrast, RSI did not influence voluntary-production or comprehension costs. This suggests that bilinguals might apply language control differently to switch languages depending on the type of switching and modality.

High fluency can improve recognition sensitivity based on learned metacognitive expectations.

Fluency of processing has shown to influence recognition judgments. Fluency most commonly induces a liberal response bias to judge fluently processed information as well-known because knowledge of a high correlation between the frequency of encounters, memory strength, and thus fluency of processing has been acquired in the past. In this study, we aimed to show that high fluency can increase recognition judgment sensitivity as well if the participants had encountered fluent and non-fluent processing during training. Thirty-three participants have been trained with a 12-element sequence in a serial reaction time task. During training, the response stimulus interval alternated block-wise between constant (fluent) and variable (non-fluent). Participants showed a higher capability of discriminating between old and new test sequences under fluent than under non-fluent test conditions. Furthermore, participants did not show any liberal or conservative bias after they have been trained with alternating fluency.

Post-execution monitoring in dishonesty

When telling a lie, humans might engage in stronger monitoring of their behavior than when telling the truth. Initial evidence has indeed pointed towards a stronger recruitment of capacity-limited monitoring processes in dishonest than honest responding, conceivably resulting from the necessity to overcome automatic tendencies to respond honestly. Previous results suggested monitoring to be confined to response execution, however, whereas the current study goes beyond these findings by specifically probing for post-execution monitoring. Participants responded (dis)honestly to simple yes/no questions in a first task and switched to an unrelated second task after a response–stimulus interval of 0 ms or 1000 ms. Dishonest responses did not only prolong response times in Task 1, but also in Task 2 with a short response–stimulus interval. These findings support the assumption that increased monitoring for dishonest responses extends beyond mere response execution, a mechanism that is possibly tuned to assess the successful completion of a dishonest act.

Learning from mistakes: Incidental encoding reveals a time-dependent enhancement of posterror target processing.

It has been known for >50 years that making an error leads to subsequent changes in performance, yet the exact nature of posterror adjustments in cognition remains debated. We posit that this is in large part due to traditional performance indices, like mean posterror response time and accuracy, being insensitive measures of trial-by-trial stimulus processing. To overcome this limitation, we devised a novel object flanker task that employed trial-unique target and distracter stimuli and was followed by a surprise recognition memory test. This allowed us to determine how errors influence incidental target and distracter encoding in a trial-specific manner. We used this approach to test the "adaptive orienting theory" of posterror processing, according to which an error triggers an initial inhibition of task processing-facilitating orienting to the error source-followed by a controlled retuning of attention to the task. To characterize the time-course of the posterror processing cascade, we combined our task with a manipulation of the response-stimulus interval (RSI), across four experiments (RSIs: 300 ms, 650 ms, ~1,000 ms; N = 96-100 per experiment). We document, for the first time, that making an error leads to a substantial (~10%) enhancement of target (but not distracter) memory on the subsequent trial, which interacts with RSI: Posterror targets were remembered better than postcorrect targets at the long (650 ms, ~1,000 ms) but not the short (300 ms) RSIs. These findings provide clear support for the adaptive orienting theory by demonstrating a novel cognitive phenomenon: a time-dependent posterror enhancement of target encoding (PETE). (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Unbiased post-error slowing in interference tasks: A confound and a simple solution

We typically slow down after committing an error, an effect termed post-error slowing (PES). Traditionally, PES has been calculated by subtracting post-correct from post-error RTs. Dutilh et al. (Journal of Mathematical Psychology, 56(3), 208-216, 2012), however, showed PES values calculated in this way are potentially biased. Therefore, they proposed to compute robust PES scores by subtracting pre-error RTs from post-error RTs. Based on data from a large-scale study using the flanker task, we show that both traditional and robust PES estimates can be biased. The source of the bias are differential imbalances in the percentage of congruent vs. incongruent post-correct, pre-error, and post-error trials. Specifically, we found that post-correct, pre-error, and post-error trials were more likely to be congruent than incongruent, with the size of the imbalance depending on the trial type as well as the length of the response-stimulus interval (RSI). In our study, for trials preceded by a 700-ms RSI, the percentages of congruent trials were 62% for post-correct trials, 66% for pre-error trials, and 56% for post-error trials. Relative to unbiased estimates, these imbalances inflated traditional PES estimates by 37% (9 ms) and robust PES estimates by 42% (16 ms) when individual-participant means were calculated. When individual-participant medians were calculated, the biases were even more pronounced (40% and 50% inflation, respectively). To obtain unbiased PES scores for interference tasks, we propose to compute unweighted individual-participant means by initially calculating mean RTs for congruent and incongruent trials separately, before averaging congruent and incongruent mean RTs to calculate means for post-correct, pre-error and post-error trials.

Watching the Brain as It (Un)Binds: Beta Synchronization Relates to Distractor-Response Binding.

Human action control relies on event files, that is, short-term stimulus-response bindings that result from the integration of perception and action. The present EEG study examined oscillatory brain activities related to the integration and disintegration of event files in the distractor-response binding (DRB) task, which relies on a sequential prime-probe structure with orthogonal variation of distractor and response relations between prime and probe. Behavioral results indicated a DRB effect in RTs, which was moderated by the duration of the response-stimulus interval (RSI) between prime response and probe stimulus onset. Indeed, a DRB effect was observed for a short RSI of 500 msec but not for a longer RSI of 2000 msec, indicating disintegration of event files over time. EEG results revealed a positive correlation between individual DRB in the RSI-2000 condition and postmovement beta synchronization after both prime and probe responses. Beamformer analysis localized this correlation effect to the middle occipital gyrus, which also showed highest coherency with precentral and inferior parietal brain regions. Together, these findings suggest that postmovement beta synchronization is a marker of event file disintegration, with the left middle occipital gyrus being a hub region for stimulus-response bindings in the visual DRB task.

Manipulations of the Response-Stimulus Intervals as a Factor Inducing Controlled Amount of Reaction Time Intra-Individual Variability.

Aggrandized fluctuations in the series of reaction times (RTs) are a very sensitive marker of neurocognitive disorders present in neuropsychiatric populations, pathological ageing and in patients with acquired brain injury. Even though it was documented that processing inconsistency founds a background of higher-order cognitive functions disturbances, there is a vast heterogeneity regarding types of task used to compute RT-related variability, which impedes determining the relationship between elementary and more complex cognitive processes. Considering the above, our goal was to develop a relatively new assessment method based on a simple reaction time paradigm, conducive to eliciting a controlled range of intra-individual variability. It was hypothesized that performance variability might be induced by manipulation of response-stimulus interval’s length and regularity. In order to verify this hypothesis, a group of 107 healthy students was tested using a series of digitalized tasks and their results were analyzed using parametric and ex-Gaussian statistics of RTs distributional markers. In general, these analyses proved that intra-individual variability might be evoked by a given type of response-stimulus interval manipulation even when it is applied to the simple reaction time task. Collected outcomes were discussed with reference to neuroscientific concepts of attentional resources and functional neural networks.

Error-induced adaptability: Behavioral and neural dynamics of response-stimulus interval modulations on posterror slowing.

Response errors often cause individuals to slow down their subsequent reactions (posterror slowing [PES]). Despite intensive investigations on PES, the adaptive nature of PES remains unresolved. Here, we systematically examined this issue by manipulating response-stimulus intervals (RSIs) and examining their influence on behaviors and neural dynamics of PES. Behavioral and electrophysiological (EEG) measures were recorded while male and female human participants performed a four-choice flanker task as RSIs were manipulated. Behaviorally, PES showed maladaptive features at short RSIs but some adaptive features at long RSIs. EEG results indicated that RSIs did not affect basic error-related processing, indexed by the same pattern in the contrasts between flanker errors and correct responses on the error-related negativity (ERN), error positivity (Pe), or theta band, no matter at short or long RSIs. However, RSIs significantly influenced postflanker error attentional adjustment, motor inhibition, and sensory sensitivity. At short RSIs, compared with postcorrect trials, postflanker error trials elicited larger beta band power and smaller P1 amplitude but did not affect alpha band power, suggesting that motor processing was inhibited, and subsequent sensory processing was impaired, but no attentional adjustment occurred. By contrast, at long RSIs, postflanker error trials led to smaller alpha and beta band power but did not affect P1 amplitude, indicating that attentional adjustment but not motor inhibition occurred, and sensory processing was not impaired. Together with behavioral results, the current study demonstrated that PES was adaptive at long RSIs but maladaptive at short RSIs. We further discuss the role of central resources in the adaptability of PES. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Response inhibition in the task-switching paradigm

In a task-switching paradigm, response repetition (RR) often produces costs in task-switch trials but smaller costs or even benefits in task-repeat trials. Response inhibition accounts consistently attribute negative RR effects to the inhibition of the previous response, but they have different views on this inhibition process. According to the task-specific inhibition hypothesis, the previous response is inhibited when the task-switch is called for; whereas according to the general inhibition hypothesis, the response was generally inhibited after the execution. The present study utilized the electroencephalographs (EEGs) to investigate the response inhibition in the task-switching paradigm, with lateralized upper-alpha and beta enhancements serving as indexes of response inhibition. In blocks with task preparation, a task cue during the response-stimulus interval (RSI) was used to indicate which task was required, and the blocks without task preparation served as the control condition. The result indicated that, during the cue-stimulus interval (CSI), lateralized upper-alpha enhancements appeared only in trials with task-switch preparation, supporting the task-specific inhibition hypothesis. By contrast, regardless of whether there was task preparation and which task to prepare, lateralized beta enhancements appeared during the RSI, which provided evidence for the general inhibition hypothesis. These results suggest the existence of two different response inhibition processes in the task-switching paradigm.

Decay of inhibition in motor imagery.

During motor imagery, global inhibition and effector-specific inhibition contribute to prevent actual movements. We investigated the decay of inhibition using an action-mode switching paradigm. Participants switched between imagined and executed hand movements. Response-stimulus intervals (RSIs) were varied (200, 700, 1,300, and 2,000 ms). As inhibition (due to imagination) or activation (due to execution) in one trial affects performance in the subsequent trial, we analysed sequential effects. Evidence for the contribution of global inhibition (e.g., switch benefits in execution [E]-imagination [I] sequences compared with I-I sequences) and effector-specific inhibition (e.g., hand repetition costs after an imagination trial) was observed. Sequential effects decreased with increasing RSIs, indicating that both forms of inhibition are subject to decay. However, the decrease of sequential effects was less pronounced for global inhibition than for effector-specific inhibition. This indicates that global inhibition may decay slowly, whereas effector-specific inhibition decays rather quickly. In conclusion, global inhibition may be at least partly implemented in all contexts in which motor imagery has to be performed, whereas effector-specific inhibition may contribute to motor imagery only as soon as the exact movement parameters are known and may decay quickly after the imagined movement has been performed.

Response repetitions in auditory task switching: The influence of spatial response distance and of the response-stimulus interval

In task switching studies, response repetition effects are typically obtained: When the task repeats, response repetitions are faster than response switches (response repetition benefit), but when the task switches, the opposite is found (response repetition cost). Previously, it was found that spatial response distance [RD] affected the response repetitions: separated response keys led to longer reaction times [RT] for response repetitions (in both task repetitions and task switches) than adjacent response keys. The goal of the present study was to replicate this RD effect in a modified setup with auditory stimuli (in Experiments 1 and 2). As we were interested in the temporal dynamics of the RD effect, we also introduced a block-wise manipulation of response-stimulus interval (RSI) in Experiment 2. RD modulated responding, replicating the results of a prior study that used visual stimuli, but only when the RSI was long. With short RSI, the RD effect was not obtained. At the same time, a long RSI led to more pronounced response repetition effects in the error rates. These results imply that response inhibition from the previous trial, which is assumed to contribute to the response repetition effect and to the modulation of responding by response distance, builds up over time.

On the ambiguity regarding the relationship between sequential congruency effects, bilingual advantages in cognitive control, and the disengagement of attention.

Grundy, Bialystok, and colleagues have reported that at short response-stimulus intervals bilinguals have smaller sequential congruency effects in flanker tasks compared to monolinguals. They interpret these differences to mean that bilinguals are more efficient at disengaging attentional control. Ten empirical studies are presented that show no differences between bilinguals and monolinguals under conditions that produced robust sequential congruency effects. These null results are discussed with respect to the rate at which sequential congruency effects dissipate and the fact these effects are not adaptive in the sense of improving overall performance. Arguments made by Goldsmith and Morton [1] that smaller sequential congruency effects should not be interpreted as “advantages” are extended. Evidence is also presented that neither simple congruency effects, nor sequential congruency effects, correlate across tasks. This lack of convergent validity is inconsistent with the hypothesis that either provides a measure of domain-general control that could underlie an advantage accrued through experience in switching languages. Results from other tasks purporting to show bilingual advantages in the disengagement of attention are also reviewed. We conclude that sequential congruency effects in nonverbal interference tasks and differences in the rate of disengaging attention are unlikely to contribute to our understanding of bilingual language control and that future research might productively examine differences in proactive rather than reactive control.