Language switching when writing: The role of phonological and orthographic overlap

While language switching of bilinguals has been investigated extensively in the spoken domain, there has been little research on switching while writing. The factors that impact written language switching may differ from those that impact language switching while speaking. Thus, the study's goal was to test to what extent phonological and/or orthographic overlap impacts written language switching. In four experiments (NExp.1 = 34; NExp. 2 = 57; NExp. 3 = 39; NExp. 4 = 39), German-English bilinguals completed a cued language switching task where responses had to be typed. To-be-named translation-equivalent concepts were selected to be similar phonologically, orthographically or neither. Participants switching between languages while writing was facilitated by both phonological and orthographic overlap. Maximum orthographic overlap between translation-equivalent words with dissimilar pronunciations facilitated switching to the extent that no switch costs could be observed. These results imply that overlapping orthography can strongly facilitate written language switching and that orthography's role should be considered more thoroughly in models of bilingual language production.

Repetition costs in task switching are not equal to cue switching costs: evidence from a cue-independent context

Recent task-switching studies highlighted the presence of feature binding processes. These studies documented that even a task-irrelevant feature (the context, henceforth) may be bound with the task and the response in each trial. When the context repeated in the following trial, it supposedly retrieved the bound features, causing benefits when the task and the response repeated and costs otherwise (i.e. full repetition benefits). In the present study, we aim to rule out an alternative explanation for such full repetition benefits in task switching. These benefits were observed in studies that used a cue-related context so that full repetition conditions always implied a cue repetition. Therefore, these full repetition benefits may be ascribed to the priming of cue encoding, instead of the binding of the context. In the present study, we implemented a similar context manipulation but used univalent target stimuli and did not present any cue. Hence, the varying context was never cue-related. We still found full repetition benefits but only when the context appeared before the target and not when they appeared simultaneously. Thus, full repetition benefits can be observed in the absence of priming of cue encoding. However, the context must occupy a prominent position (i.e. at the beginning of the trial). These results, therefore, reinforce the hypothesis that full repetition benefits stem from binding processes that take place on a trial-by-trial basis and involve both task-relevant (the task and the response) and task-irrelevant features (the context).

Reassessing the role of language dominance in n-2 language repetition costs as a marker of inhibition in multilingual language switching

Speaking two or more languages shows bilingual flexibility, but flexible switching requires language control and often incurs performance costs. We examined inhibitory control assessing n-2 repetition costs when switching three languages (L1 [German], L2 [English], L3 [French]). These costs denote worse performance in n-2 repetitions (e.g., L2-L3-L2) than in n-2 nonrepetitions (e.g., L1-L3-L2), indicating persisting inhibition. In two experiments (n = 28 in Experiment 1; n = 44 in Experiment 2), n-2 repetition costs were observed, but only for L2. Looking into L2 trials specifically, we found n-2 repetition costs when switching back to L2 from the still weaker L3 but not when returning from the stronger L1, suggesting that L2 is a strong competitor for L3 (requiring L2 inhibition) but less so for L1. Finding n-2 repetition costs supports an inhibitory account of language control in general, but our study shows only partial evidence for the theoretically assumed more specific relation between language dominance and language inhibition (i.e., only for dominance relations with respect to L1 and L3 when switching back to L2). Taken together, the findings thus suggest the need for further refinement of the concept of language dominance and its relation to inhibition. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Evidence of task-triggered retrieval of the previous response: a binding perspective on response-repetition benefits in task switching

In task switching, response repetitions (RRs) usually yield performance benefits as compared to response switches, but only when the task also repeats. When the task switches, RR benefits vanish or even turn into costs, yielding an interaction between repeating versus switching the task and the response (the RR effect). Different theoretical accounts for this RR effect exist, but, in the present study, we specifically tested a prediction derived from binding and retrieval accounts. These maintain that repeating the task retrieves the previous-trial response, thus causing RR benefits. Retrieval is possible due to the task-response binding formed in the previous trial. We employed a task-switching paradigm with three response options that allowed us to differentiate error types. Across two experiments (N = 46 and N = 107) we showed that response-repetition errors in response-switch trials were more likely in task repetitions than in task switches, supporting the notion that the previous response is retrieved by the repeating task, despite being wrong. Such a finding is in line with binding and retrieval accounts but cannot be easily accommodated by the competing theoretical accounts. Thus, the present study indicates task-response binding as an important mechanism underlying RR benefits in task repetitions.

Binding of task-irrelevant contextual features in task switching

Research in attention and action control produced substantial evidence suggesting the presence of feature binding. This study explores the binding of task-irrelevant context features in cued task switching. We predicted that repeating a context feature in trial n retrieves the trial n - 1 episode. Consequently, performance should improve when the retrieved features match the features of the current trial. Two experiments (N = 124; N = 96) employing different tasks and materials showed that repeating the task-irrelevant context improved performance when the task and the response repeated. Furthermore, repeating the task-irrelevant context increased task repetition benefits only when the context feature appeared synchronously with cue onset, but not when the context feature appeared with a 300-ms delay (Experiment 1). Similarly, repeating the task-irrelevant context improved performance when the task and the response repeated only when the context feature was part of the cue, and not when it was part of the target (Experiment 2). Taken together, binding and retrieval processes seem to play a crucial role in task switching, alongside response inhibition processes. In turn, our study provided a better understanding of binding and retrieval of task-irrelevant features in general, and specifically on how they modulate response repetition benefits in task repetitions.

What have we learned from 15 years of research on cross-situational word learning? A focused review

In 2007 and 2008, Yu and Smith published their seminal studies on cross-situational word learning (CSWL) in adults and infants, showing that word-object-mappings can be acquired from distributed statistics despite in-the-moment uncertainty. Since then, the CSWL paradigm has been used extensively to better understand (statistical) word learning in different language learners and under different learning conditions. The goal of this review is to provide an entry-level overview of findings and themes that have emerged in 15 years of research on CSWL across three topic areas (mechanisms of CSWL, CSWL across different learner and task characteristics) and to highlight the questions that remain to be answered.

On the reliability of behavioral measures of cognitive control: retest reliability of task-inhibition effect, task-preparation effect, Stroop-like interference, and conflict adaptation effect

This study examined the reliability (retest and split-half) of four common behavioral measures of cognitive control. In Experiment 1 (N = 96), we examined N – 2 task repetition costs as a marker of task-level inhibition, and the cue-stimulus interval (CSI) effect as a marker of time-based task preparation. In Experiment 2 (N = 48), we examined a Stroop-like face-name interference effect as a measure of distractor interference control, and the sequential congruency effect (“conflict adaptation effect”) as a measure of conflict-triggered adaptation of cognitive control. In both experiments, the measures were assessed in two sessions on the same day, separated by a 10 min-long unrelated filler task. We observed substantial experimental effects with medium to large effect sizes. At the same time, split-half reliabilities were moderate, and retest reliabilities were poor, for most measures, except for the CSI effect. Retest reliability of the Stroop-like effect was improved when considering only trials preceded by congruent trials. Together, the data suggest that these cognitive control measures are well suited for assessing group-level effects of cognitive control. Yet, except for the CSI effect, these measures do not seem suitable for reliably assessing interindividual differences in the strength of cognitive control, and therefore are not suited for correlational approaches. We discuss possible reasons for the discrepancy between robustness at the group level and reliability at the level of interindividual differences.

Assessing the Evidence for Asymmetrical Switch Costs and Reversed Language Dominance Effects - A Meta-Analysis

Two seemingly counterintuitive phenomena - asymmetrical language switch costs and the reversed language dominance effect - prove to be particularly controversial in the literature on language control. Asymmetrical language switch costs refer to the larger costs for switching into the dominant language compared to switching into the less dominant language, both relative to staying in either one language. The reversed language dominance effect refers to longer reaction times when in the more dominant of the two languages in situations that require frequent language switching (i.e., mixed-language blocks). The asymmetrical language switch costs are commonly taken as an index for processes of transient, reactive inhibitory language control, whereas the reversed language dominance effect is taken as an index for sustained, proactive inhibitory language control. In the present meta-analysis, we set out to establish the empirical evidence for these two phenomena using a Bayesian linear mixed effects modelling approach. Despite the observation of both phenomena in some studies, our results suggest that overall, there is little evidence for the generality and robustness of these two effects, and this holds true even when conditions - such as language proficiency and preparation time manipulations - were included as moderators of these phenomena. We conclude that asymmetrical switch costs and the reversed language dominance effect are important for theory development, but their utility for theory testing is limited due to their lack of robustness and the absence of confirmed moderatory variables.

Interplay of morphological configuration and language switching in numerical processing and word processing

The aim of the present study was to examine the interplay of morphological configuration switching and language switching. The morphological configuration is present in word-formation whenever a word contains more than one free morpheme. The morphological configuration is variable both within and between languages for example in two-digit number names (is the decade named first as in twenty-one or the unit named first as in seventeen) and in compound words (is the modifier or the head named first). In the present experiments, participants had to switch between morphological configurations and between languages (German, English, and Spanish). Language-switch cost was measured as the performance difference between language-switch trials and language-repetition trials. In Experiments 1 and 2, participants performed language-comprehension tasks on two-digit numbers and a language-production task on compound words in Experiment 3. All three experiments revealed an under-additive switch cost pattern in which a larger language-switch cost occurred in morphological configuration-repetition trials than in morphological configuration-switch trials. Thus, the present data indicate integration of the morphological configuration and language into one language-related schema-irrespective of the language task (comprehension vs. production) and the type of stimuli (number words vs. compound nouns). (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Exploring the role of verbal-semantic overlap in response-effect compatibility

According to ideomotor accounts, actions are cognitively represented by their sensory effects. The response-effect compatibility (R-E compatibility) paradigm investigates this notion by presenting predictable effect stimuli that are produced by the response ("response effects"). The R-E compatibility effect denotes the finding of better performance in R-E compatible conditions than in incompatible conditions, suggesting that anticipation of the effect stimulus primes the response. Most previous studies employed perceptual R-E overlap manipulations (e.g., spatial, temporal or phonological overlap of response and predictable response effect). In the present study, we examined verbal-semantic response-effect overlap. In Experiment 1, we used category words as vocal responses and semantically associated vs. non-associated exemplar words for auditory response effects (or exemplar words as responses and category words as effects, respectively) to manipulate verbal-semantic R-E overlap without perceptual-phonological similarity. In Experiments 2A and 2B, we used the response word also as an "identical" auditory effect word (i.e., both verbal-semantic and perceptual-phonological R-E overlap). An R-E compatibility effect was observed only when there was both verbal-semantic and perceptual-phonological R-E overlap. These data suggest that anticipation of perceptual response features may be critical in the R-E compatibility paradigm, whereas the role of verbal-semantic processes in response-effect anticipation still needs to be established more firmly. We discuss how perceptual and conceptual processes can interact in ideomotor control of action.

Multilingual two-digit number naming: The influence of composition rules on language switching

The aim of this study was to examine language switching in a two-digit number naming task. In contrast to single digits, two-digit numbers have a composition rule (i.e., morphological configuration) that may differ between languages. For example, the Arabic number 21 is read with an inverted composition rule in German (unit before decade) and a non-inverted composition rule in English (decade before unit). In the present experiment, one group of German native speakers and one group of Spanish native speakers had to name two-digit numbers in German, English, or Spanish. The results demonstrate a language-switch cost, revealing better performance in language repetition than in language-switch trials. This switch cost was further modulated by repeating or switching the composition rule, since the language repetition benefit (i.e., the switch cost) was reduced in trials with composition-rule switches compared with trials with composition-rule repetitions. This finding indicates that the language in which the number word has to be produced and its composition rule are not switched independently but rather may be integrated into one language schema.

Sensory-motor modality compatibility in multitasking: The influence of processing codes

Sensory-motor modality compatibility is defined as the similarity between the sensory modality and the modality of response-related effects. Previous dual-task and task-switching studies have shown higher performance costs for coordinating relatively incompatible sensory-motor modality mappings (i.e., auditory-manual and visual-vocal) compared to more compatible mappings (i.e., auditory-vocal and visual-manual). Until now, however, little attention has been paid to potential variability in effects of modality compatibility depending on different processing codes. In the present study, we independently varied the processing codes of input and output (nonverbal-spatial, nonverbal-nominal, verbal-spatial, verbal-nominal) while participants switched between incompatible and compatible sensory-motor modality mappings. Beside higher switch costs for switching between incompatible sensory-motor modality mappings than for switching between compatible mappings, the results revealed stronger effects of modality compatibility on switch costs for verbal input than for nonverbal input codes. This suggests that priming mechanisms between sensory input and compatible motor output are modulated by the processing code of the sensory input. As possible explanations, we assume a higher degree of concordance with output processing codes as well as stronger associations with potential response effects for verbal than for nonverbal input.

Exploring the representational basis of response-effect compatibility: Evidence from bilingual verbal response-effect mappings

The ideomotor principle states that actions are represented by their anticipated sensory effects. This notion is often tested using the response-effect compatibility (REC) paradigm, where participants' responses are followed either by a compatible or incompatible response effect (e.g., an effect on the right side after a right-hand response is considered R-E compatible due to the spatial overlap, whereas an effect on the left side after the right-hand response is considered incompatible). Shorter reaction times are typically observed in the compatible condition compared to the incompatible condition (i.e., REC effect), suggesting that effect anticipation plays a role in action control. Previous evidence from verbal REC suggested that effect anticipation can be due to conceptual R-E overlap, but there was also phonological overlap (i.e., anticipated reading of a word preceded by the vocal response of saying that very word). To examine the representational basis of REC, in three experiments, we introduced a bilingual R-E mapping to exclude phonological R-E overlap (i.e., in the R-E compatible condition, the translation equivalent of the response word is presented as an effect word in a different language). Our findings show that the REC effect is obtained when presenting the effect word in the same language as the response (i.e., monolingual condition), but the compatibility effect was not found when the semantically same word is presented in a different language, suggesting no conceptually generalized REC in a bilingual setting. (232 words).

The role of learning in sensory-motor modality switching

Previous research has indicated that modality switching is considerably affected by modality compatibility. It has been shown that switch costs are higher for switching between relatively incompatible sensory-motor modality mappings (i.e., auditory-manual and visual-vocal) compared to switching between compatible mappings (i.e., auditory-vocal and visual-manual). So far, however, it has been unclear whether these findings are influenced by learning processes resulting from very small stimulus sets and a large number of stimulus repetitions. In the present study, we investigated the role of learning concept-to-category associations (Experiment 1) as well as influences of learning concept-to-modality mappings (Experiment 2) on sensory-motor modality switching in semantic categorizations. The results of both experiments revealed shorter overall reaction times due to learning. Additionally, learning of concept-to-category associations (Experiment 1) led to a significant reduction of modality switch costs. Interestingly, however, modality-compatibility effects were neither significantly influenced by learning of concept-to-category associations nor by learning of concept-to-modality mappings. Thus, the present study provides first evidence that learning on the semantic level influences modality switching but it does not significantly affect modality compatibility.

Exploring Modality Compatibility in the Response-Effect Compatibility Paradigm

According to ideomotor theory, action planning is based on anticipatory perceptual representations of action-effects. This aspect of action control has been investigated in studies using the response-effect compatibility (REC) paradigm, in which responses have been shown to be facilitated if ensuing perceptual effects share codes with the response based on dimensional overlap (i.e., REC). Additionally, according to the notion of ideomotor compatibility, certain response-effect (R-E) mappings will be stronger than others because some response features resemble the anticipated sensory response effects more strongly than others (e.g., since vocal responses usually produce auditory effects, an auditory stimulus should be anticipated in a stronger manner following vocal responses rather than following manual responses). Yet, systematic research on this matter is lacking. In the present study, two REC experiments aimed to explore the influence of R-E modality mappings. In Experiment 1, vocal number word responses produced visual effects on the screen (digits vs. number words; i.e., visual-symbolic vs. visual-verbal effect codes). The REC effect was only marginally larger for visual-verbal than for visual-symbolic effects. Using verbal effect codes in Experiment 2, we found that the REC effect was larger with auditory-verbal R-E mapping than with visual-verbal R-E mapping. Overall, the findings support the hypothesis of a role of R-E modality mappings in REC effects, suggesting both further evidence for ideomotor accounts as well as code-specific and modality-specific contributions to effect anticipation.

Chunking in Task Sequences Modulates Task Inhibition

In a study of the formation of representations of task sequences and its influence on task inhibition, participants first performed tasks in a predictable sequence (e.g., ABACBC) and then performed the tasks in a random sequence. Half of the participants were explicitly instructed about the predictable sequence, whereas the other participants did not receive these instructions. Task-sequence learning was inferred from shorter reaction times (RTs) in predictable relative to random sequences. Persisting inhibition of competing tasks was indicated by increased RTs in n — 2 task repetitions (e.g., ABA) compared with n — 2 nonrepetitions (e.g., CBA). The results show task-sequence learning for both groups. However, task inhibition was reduced in predictable relative to random sequences among instructed-learning participants who formed an explicit representation of the task sequence, whereas sequence learning and task inhibition were independent in the noninstructed group. We hypothesize that the explicit instructions led to chunking of the task sequence, and that n — 2 repetitions served as chunk points (ABA-CBC), so that within-chunk facilitation modulated the inhibition effect.

Highly proficient bilinguals implement inhibition: Evidence from n-2 language repetition costs

Several, but not all, models of language control assume that highly proficient bilinguals implement little to no inhibition during bilingual language production. In the current study, we tested this assumption with a less equivocal marker of inhibition (i.e., n-2 language repetition costs) than previous language switching studies have. N-2 language repetition costs denote worse performance when switching back to a recently abandoned language (i.e., worse performance in ABA language sequences than CBA sequences, where A, B, and C refer to different languages). Whereas this marker has solely been used to investigate second-language learners in prior studies, we examined highly proficient bilinguals. The results showed that substantial n-2 language repetition costs can be observed with highly proficient bilinguals. Moreover, this inhibition effect was substantial for all 3 languages, but larger for the 2 dominant languages (Turkish and German) relative to the less proficient language (English). These findings indicate that even highly proficient bilinguals implement inhibition to restrict language production to the target language.

The role of sensory-motor modality compatibility in language processing

Language processing requires the combination of compatible (auditory-vocal and visual-manual) or incompatible (auditory-manual and visual-vocal) sensory-motor modalities, and switching between these sensory-motor modality combinations is very common in every-day life. Sensory-motor modality compatibility is defined as the similarity of stimulus modality and the modality of response-related sensory consequences. We investigated the influence of sensory-motor modality compatibility during performing language-related cognitive operations on different linguistic levels. More specifically, we used a variant of the task-switching paradigm, in which participants had to switch between compatible or between incompatible sensory-motor modality combinations during a verbal semantic categorization (Experiment 1) or during a word-form decision (Experiment 2). The data show higher switch costs (i.e., higher reaction times and error rates in switch trials compared to repetition trials) in incompatible sensory-motor modality combinations than in compatible sensory-motor modality combinations. This was true for every language-related cognitive operation, regardless of the individual linguistic level. Taken together, the present study demonstrates that sensory-motor modality compatibility plays an important role in modality switching during language processing.

A sentence to remember: instructed language switching in sentence production

In the current study, we set out to investigate the influence of a sentence context on language switching. The task required German-English bilinguals to produce responses based on an alternating language sequence (L1-L1-L2-L2- …) and concepts in a specific sequential order. The concept sequence was either a sentence which was syntactically correct in both languages (language-unspecific sentence), a sentence which was correct in just one language (language-specific sentence) or a sentence which was syntactically incorrect in both languages (scrambled sentence). No switch costs were observed in language-unspecific sentences. Consequently, switch costs were smaller in those sentences than in the language-specific or scrambled sentences. The language-specific and scrambled sentence did not differ with respect to switch costs. These results demonstrate an important role of sentence context for language switch costs and were interpreted in terms of language interference and preparation processes.

A review of ideomotor approaches to perception, cognition, action, and language: advancing a cultural recycling hypothesis

The term "cultural recycling" derives from the neuronal recycling hypothesis, which suggests that representations of cultural inventions like written words, Arabic numbers, or tools can occupy brain areas dedicated to other functions. In the present selective review article, we propose a recycling hypothesis for the ideomotor mechanism. The ideomotor approach assumes that motor actions are controlled by the anticipation of the expected perceptual consequences that they aim to generate in the environment. Arguably, such action-perception mechanisms contribute to motor behaviour for human and non-human animals since millions of years. However, recent empirical studies suggest that the ideomotor mechanism can also contribute to word processing, number representation, and arithmetic. For instance, it has been shown that the anticipatory simulation of abstract semantics, like the numerical quantitative value of three items can prime processing of the associated Arabic number "3". Arabic numbers, words, or tools represent cultural inventions, so that, from a theoretical perspective, we suggest an ideomotor recycling hypothesis for the interaction with such artefacts. In this view, the ideomotor mechanism spreads its influence to other functions beyond motor control, and is recycled to flexibly adapt different human behaviours towards dealing with more abstract concepts.

The minimum requirements of language control: evidence from sequential predictability effects in language switching

The current study systematically examined the influence of sequential predictability of languages and concepts on language switching. To this end, 2 language switching paradigms were combined. To measure language switching with a random sequence of languages and/or concepts, we used a language switching paradigm that implements visual cues and stimuli. The other paradigm implements a fixed sequence of languages and/or concepts to measure predictable language switching. Four experiments that used these 2 paradigms showed that switch costs were smaller when both the language and concept were predictably known, whereas no overall switch cost reduction was found when just the language or concept was predictable. These results indicate that knowing both language and concept (i.e., response) can resolve language interference. However, interference resolution does not start solely based on the knowledge of which concept or language one has to produce. We discuss how existent models should be revised to accommodate these results.

Bilingual control: sequential memory in language switching

To investigate bilingual language control, prior language switching studies presented visual objects, which had to be named in different languages, typically indicated by a visual cue. The present study examined language switching of predictable responses by introducing a novel sequence-based language switching paradigm. In 4 experiments, sequential responses (i.e., weekdays, numbers or new sequences) and an alternating language sequence (e.g., L1-L1-L2-L2) were implemented, both of which were memory based. Our data revealed switch costs, showing that a language switch is associated with worse performance compared with a language repetition, and mixing costs, which constitutes the performance difference between pure and mixed language blocks, even while producing entirely predictable responses (i.e., language and concept). Additionally, we found these switch costs with overlearned and new sequences and found that switch costs were reduced with longer preparation time. The obtained data are consistent with a proactive interference account, such as the inhibitory control model.

The influence of action effects in task-switching

According to ideomotor theories, intended effects caused by a certain action are anticipated before action execution. In the present study, we examined the question of whether action effects play a role in cued task-switching. In our study, the participants practiced task-response-effect mappings in an acquisition phase, in which action effects occur after a response in a certain task context. In the ensuing transfer phase, the previously practiced mappings were changed in a random, unpredictable task-response-effect mapping. When changed into unpredictable action-effects, RT as well as switch-costs increased, but this occurred mainly in trials with short preparation time and not with long preparation time. Moreover, switch costs were generally smaller with predictable action-effects than with unpredictable action-effects. This suggests that anticipated task-specific action effects help to activate the relevant task-set before task execution when the task is not yet already prepared based on the cue.

Differential roles of inferior frontal and inferior parietal cortex in task switching: evidence from stimulus-categorization switching and response-modality switching

We used fMRI to investigate both common and differential neural mechanisms underlying two distinct types of switching requirements, namely switching between stimulus categorizations (color vs. form) and switching between response modalities (hand vs. foot responses). Both types of switching induced similar behavioral shift costs. However, at the neural level, switching between stimulus categorizations led to left-hemispheric activations including the inferior frontal gyrus as well as the intraparietal sulcus extending to the superior parietal gyrus and the supramarginal gyrus. In contrast, switching between response modalities was associated mainly with left-hemispheric activation of the intraparietal sulcus and the supramarginal gyrus. A conjunction analysis indicated common activation of the left intraparietal sulcus and the supramarginal gyrus for both types of switching. Together, these results qualify previous claims about a general role of the left prefrontal cortex in task control by suggesting that the left inferior frontal gyrus is specifically involved in switching between stimulus categorizations, whereas parietal cortex is more generally implicated in the selection of action rules.

The dissipating task-repetition benefit in cued task switching: task-set decay or temporal distinctiveness?

Decay of task-set activation, as commonly assumed in models of task switching, has been thought to be indexed by manipulating the response-to-cue interval (RCI) in a task-cuing paradigm. We propose an alternative account for RCI effects suggesting that episodic task retrieval is modulated by temporal distinctiveness, which we define as the ratio between previous RCI and current RCI. In Experiment 1, increasing RCI decreased the task-repetition benefit, but the slope of the RCI function depended on the range of RCIs rather than on the absolute duration of the RCI. In Experiment 2, the RCIs were blocked or random, and in Experiment 3, trial-wise predictability of RCIs was manipulated. RCI influenced the task-repetition benefit only when RCI changed from the previous to the current trial. Experiment 4 used two cues for each task and dissociated cue-repetition priming from task-repetition priming, suggesting that it is episodic task-set retrieval that is influenced by temporal distinctiveness. We discuss theoretical implications for persisting-task-set-activation theories and the relation to long-term decay, inhibition, and temporal preparation in task switching.

Temporal distinctiveness and repetition benefits in task switching: Disentangling stimulus-related and response-related contributions

In cued task switching, decreasing switch costs with increasing response-to-cue interval (RCI) is a typical finding. The traditional account assumes an underlying process of task-set decay. In contrast, we suggest that these RCI effects are due to the influence of temporal distinctiveness on cue-based task retrieval (or reactivation). The present study explored the task-set components that are affected by temporal distinctiveness. According to the idea that a task set consists of response-related components and stimulus-related components, we manipulated response valence (bivalent vs. univalent) in Experiment 1. The results showed that lengthening the RCI leads to a loss of a task-repetition benefit, mainly when the RCI changed from the previous trial to the current trial, but this data pattern did not depend on response valence. In Experiment 2, stimulus valence was manipulated. The results revealed substantially stronger RCI effects with bivalent stimuli than with univalent stimuli. Taken together, the data are inconsistent with task-set decay accounts and suggest that the influence of RCI in task switching modulates cue-based retrieval of stimulus-related task components, such as biasing parameters.

Control and interference in task switching--a review

The task-switching paradigm offers enormous possibilities to study cognitive control as well as task interference. The current review provides an overview of recent research on both topics. First, we review different experimental approaches to task switching, such as comparing mixed-task blocks with single-task blocks, predictable task-switching and task-cuing paradigms, intermittent instructions, and voluntary task selection. In the 2nd part, we discuss findings on preparatory control mechanisms in task switching and theoretical accounts of task preparation. We consider preparation processes in two-stage models, consider preparation as an all-or-none process, address the question of whether preparation is switch-specific, reflect on preparation as interaction of cue encoding and memory retrieval, and discuss the impact of verbal mediation on preparation. In the 3rd part, we turn to interference phenomena in task switching. We consider proactive interference of tasks and inhibition of recently performed tasks indicated by asymmetrical switch costs and n-2 task-repetition costs. We discuss stimulus-based interference as a result of stimulus-based response activation and stimulus-based task activation, and response-based interference because of applying bivalent rather than univalent responses, response repetition effects, and carryover of response selection and execution. In the 4th and final part, we mention possible future research fields.

Evidence for a Role of the Responding Agent in the Joint Compatibility Effect

The present study explored the role of the responding agent in a social context. To do so, we developed a compatibility task with socially relevant but task-irrelevant stimuli (own face, neutral face, and a friend's face). Participants were required to perform naming responses to coloured diamonds, while the faces were presented as irrelevant stimuli. We observed faster responses in face–name compatible than in incompatible conditions. When the task was distributed among two friends, we observed a compatibility effect in a joint go/no-go condition, in which both participants performed their go/no-go tasks together. In contrast, no compatibility effect was obtained in an individual go/no-go condition. Further, the experiment showed that this joint compatibility effect was based on the compatibility between the irrelevant face and the responding agent. This result demonstrates that features of the responding agent play a crucial role in the joint compatibility effect.

The role of preparation and cue-modality in crossmodal task switching

The present study examined the effects of cue-based preparation and cue-target modality mapping in crossmodal task switching. In two experiments, we randomly presented lateralized visual and auditory stimuli simultaneously. Subjects were asked to make a left/right judgment for a stimulus in only one of the modalities. Prior to each trial, the relevant stimulus modality was indicated by a visual or auditory cue. The cueing interval was manipulated to examine preparation. In Experiment 1, we used a corresponding mapping of cue-modality and stimulus modality, whereas in Experiment 2 the mapping of cue and stimulus modalities was reversed. We found reduced modality-switch costs with a long cueing interval, showing that attention shifts to stimulus modalities can be prepared, irrespective of cue-target modality mapping. We conclude that perceptual processing in crossmodal switching can be biased in a preparatory way towards task-relevant stimulus modalities.

Inhibition in language switching: what is inhibited when switching between languages in naming tasks?

When people switch between languages, inhibition of currently irrelevant languages is assumed to occur. The authors examined inhibition of irrelevant languages with a cued language-switching paradigm. A cue indicated in which of 3 languages (German, English, or French) a visual stimulus was to be named. In 2 experiments, the authors found that naming latencies were increased in n-2 language repetitions (e.g., German/English/German) compared with in n-2 language nonrepetitions (e.g., French/English/German). This difference (n-2 repetition costs) indicates persisting inhibition of abandoned languages. It is important to note that n-2 language-repetition costs also occurred in conditions in which the language but not the cue (Experiment 1) or the stimulus/response set (Experiment 2) repeated from trial n-2 to trial n. These data demonstrate that inhibition is not restricted to a specific cue or stimulus/response set. Rather, the data suggest more global inhibitory processes that affect the mental representation of competing languages.

Response selection and response execution in task switching: evidence from a go-signal paradigm

The present study used a go/no-go signal delay (GSD) to explore the role of response-related processes in task switching. A go/no-go signal was presented at either 100 ms or 1,500 ms after the stimulus. Participants were encouraged to use the GSD for response selection and preparation. The data indicate that the opportunity to select and prepare a response (i.e., long GSD) resulted in a substantial reduction of task-shift costs (Experiment 1) and n-2 task-repetition costs (i.e., backward inhibition; Experiment 2) in the current trial. These results suggest that interference from the preceding trial can be resolved during response selection and preparation. Furthermore, the shift costs and the n-2 repetition costs after no-go trials with long GSD (i.e., response selection but no execution) were markedly smaller than after go trials. These findings suggest that the interference that gives rise to shift costs and n-2 repetition costs is related not solely to response selection but also to response execution. Thus, the present study demonstrates dissociable contributions of response selection and response execution to interference effects in task switching.

Switching of response modalities

When participants perform a sequence of different tasks, it is assumed that the engagement in one task leads to the inhibition of the previous task. This inhibition persists and impairs performance when participants switch back to this (still inhibited) task after only one intermediate trial. Previous task-switching studies on this issue have defined different tasks at the level of stimulus categorization. In our experiments we used different response modalities to define tasks. Participants always used the same stimulus categorization (e.g., categorize a digit as odd vs. even), but had to give a vocal, finger, or foot response (A, B, or C). Our results showed a higher reaction time and error rate in ABA sequences than in CBA sequences, indicating n - 2 repetition cost as a marker for persisting task inhibition. We assume that different response modalities can define a task and are inhibited in a "task switch" in the same way as stimulus categories are inhibited.

Effects of switching between leftward and rightward pro- and antisaccades

Previous studies suggested that random switching between pro- and antisaccades increases errors in both tasks. However, little is known about the effects of switching between leftward and rightward saccades (response switching). The present study investigated task and response switching using an alternating runs procedure. Tasks (i.e., prosaccades versus antisaccades) were switched every second trial. Response switches (i.e., leftward saccades versus rightward saccades) were counterbalanced across tasks and task-switching conditions. Task switching increased errors in both tasks. Response switching increased errors when antisaccades were preceded by antisaccades but not when antisaccades were preceded by prosaccades or for prosaccades regardless of the preceding saccade type. The task-switch effects suggest that both pro- and antisaccade trials activate specific production rules that can persist in a subsequent trial. The differential response-switch effects may reflect different modes of response activation in pro- and antisaccades (sensorimotor transformation of visual information versus selection of motor programs).

Effects of response selection on the task repetition benefit in task switching

A task switch typically leads to worse performance than a repetition does. This shift cost can be reduced with sufficient task preparation time, but a residual cost usually remains. We propose that a large part of this residual cost is caused by an activation bias produced by response selection processes in the preceding trial. In our experiments, we manipulated response selection requirements using a go/no-go methodology. The residual shift cost disappeared after no-go trials, suggesting that response selection is crucial to establish an activation bias for the current category-response rules and that this bias persists into the next trial. A comparison with a go-only group confirmed this analysis by revealing no differences in preparatory strategy due to the inclusion of no-go trials. In addition, no-go trials had no significant effects on subsequent trials in a single-task experiment, suggesting that no-go trials are not coded as a task different from go trials and that there is no inhibition of the prepared task in a no-go trial. We thus conclude that a persisting activation bias of response rules plays a major role in task switching.

Inhibition of Response Mode in Task Switching

Abstract. Task inhibition was explored in two experiments that employed a paradigm in which participants switched among three tasks. Two tasks required manual choice responses based on numerical judgment (parity or magnitude), whereas a third task required an unconditional double-press of both response keys. Both experiments showed that switching to a just-abandoned task (n-2 task repetition) generally leads to a performance cost relative to switching to another task. Specifically, this task inhibition effect also occurred for the double-press task, suggesting inhibition of response mode. Prolonging the task-cuing interval showed that advance task preparation reduced only inhibition of the double-press task but not of the choice tasks (Experiment 1). Prolonging the response-cue interval led to a decrease of the inhibition effect in all tasks (Experiment 2), suggesting a time-based release of task inhibition. Together, the experiments support the notion of a response-related component of task inhibition.