Transfer of task-probability-induced biases in parallel dual-task processing occurs in similar, but is constraint in distinct task sets.

Although humans often multitask, little is known about how the processing of concurrent tasks is managed. The present study investigated whether adjustments in parallel processing during multitasking are local (task-specific) or global (task-unspecific). In three experiments, participants performed one of three tasks: a primary task or, if this task did not require a response, one of two background tasks (i.e., prioritized processing paradigm). To manipulate the degree of parallel processing, we presented blocks consisting mainly of primary or background task trials. In Experiment 1, the frequency manipulation was distributed equally across the two background tasks. In Experiments 2 and 3, only one background task was frequency-biased (inducer task). The other background task was presented equally often in all blocks (diagnostic task) and served to test whether processing adjustments transferred. In all experiments, blocks with frequent background tasks yielded stronger interference between primary and background tasks (primary task performance) and improved background task performance. Thus, resource sharing appeared to increase with high background task probabilities even under triple task requirements. Importantly, these adjustments generalized across the background tasks when they were conceptually and visually similar (Experiment 2). Implementing more distinct background tasks limited the transfer: Adjustments were restricted to the inducer task in background task performance and only small transfer was observed in primary task performance (Experiment 3). Overall, the results indicate that the transfer of adjustments in parallel processing is unrestricted for similar, but limited for distinct tasks, suggesting that task similarity affects the generality of resource allocation in multitasking. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Exploring behavioral adjustments of proportion congruency manipulations in an Eriksen flanker task with visual and auditory distractor modalities.

The present study investigated global behavioral adaptation effects to conflict arising from different distractor modalities. Three experiments were conducted using an Eriksen flanker paradigm with constant visual targets, but randomly varying auditory or visual distractors. In Experiment 1, the proportion of congruent to incongruent trials was varied for both distractor modalities, whereas in Experiments 2A and 2B, this proportion congruency (PC) manipulation was applied to trials with one distractor modality (inducer) to test potential behavioral transfer effects to trials with the other distractor modality (diagnostic). In all experiments, mean proportion congruency effects (PCEs) were present in trials with a PC manipulation, but there was no evidence of transfer to diagnostic trials in Experiments 2A and 2B. Distributional analyses (delta plots) provided further evidence for distractor modality-specific global behavioral adaptations by showing differences in the slope of delta plots with visual but not auditory distractors when increasing the ratio of congruent trials. Thus, it is suggested that distractor modalities constrain global behavioral adaptation effects due to the learning of modality-specific memory traces (e.g., distractor-target associations) and/or the modality-specific cognitive control processes (e.g., suppression of modality-specific distractor-based activation). Moreover, additional analyses revealed partial transfer of the congruency sequence effect across trials with different distractor modalities suggesting that distractor modality may differentially affect local and global behavioral adaptations.

Reactive and proactive control processes in voluntary task choice.

Deciding which task to perform when multiple tasks are available can be influenced by external influences in the environment. In the present study, we demonstrate that such external biases on task-choice behavior reflect reactive control adjustments instead of a failure in control to internally select a task goal. Specifically, in two experiments we delayed the onset of one of two task stimuli by a short (50 ms), medium (300 ms), or long (1,000 ms) stimulus-onset asynchrony (SOA) within blocks while also varying the relative frequencies of short versus long SOAs across blocks (i.e., short SOA frequent vs. long SOA frequent). Participants' task choices were increasingly biased towards selecting the task associated with the first stimulus with increasing SOAs. Critically, both experiments also revealed that the short-to-medium SOA bias was larger in blocks with more frequent long SOAs when participants had limited time to prepare for an upcoming trial. When time to select an upcoming task was extended in Experiment 2, this interaction was not significant, suggesting that the extent to which people rely on reactive control adjustments is additionally modulated by proactive control processes. Thus, the present findings also suggest that voluntary task choices are jointly guided by both proactive and reactive processes, which are likely to adjust the relative activation of different task goals in working memory.

The role of temporal order of relevant and irrelevant dimensions within conflict tasks.

Conflict tasks are commonly used to investigate control processes under situations of relevant and irrelevant sources of information. In addition to compatibility effects at a mean behavioral level, delta plot analyses of reaction time distributions reveal that the compatibility effect generally increases with time (i.e., positive delta plot slopes) across most conflict-like tasks. Critically, the underlying causes of the increasing delta plot slopes with different types of distractors are still poorly understood. The present study tested whether the relative onset of target-to-distractor processing affects the delta plot slope. Specifically, we manipulated the temporal order of relevant and irrelevant dimensions within an Eriksen flanker task (Experiment [Exp.] 1), an Arrow-Simon task (Exp. 2), and a manual Stroop task (Exp. 3a/3b). The results of the Eriksen flanker task and Arrow-Simon task revealed that the delta plots slopes were less increasing (and instead rather decreasing) when the irrelevant dimension appears first (IR condition) compared to the reversed order (RI condition)-consistent with the idea that the underlying mechanism driving the slope of the delta plot is the temporal overlap of activation between the relevant and irrelevant dimensions. In contrast, for the Stroop task, the delta plots in the RI condition were not more increasing than the ones for the IR condition. Overall, these results suggest that the temporal properties strongly influence delta plot shape, but that the temporal dynamics operating in the flanker task and the Arrow-Simon task differs from the Stroop task, at least under conditions where relevant and irrelevant information is presented sequentially. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The Role of Predictability During Negation Processing in Truth-Value Judgment Tasks.

In experiments investigating the processing of true and false negative sentences, it is often reported that polarity interacts with truth-value, in the sense that true sentences lead to faster reaction times than false sentences in affirmative conditions whereas the same does not hold for negative sentences. Various reasons for this difference between affirmative and negative sentences have been discussed in the literature (e.g., lexical associations, predictability, ease of comparing sentence and world). In the present study, we excluded lexical associations as a potential influencing factor. Participants saw artificial visual worlds (e.g., a white square and a black circle) and corresponding sentences (i.e., "The square/circle is (not) white"). The results showed a clear effect of truth-value for affirmative sentences (true faster than false) but not for negative sentences. This result implies that the well-known truth-value-by-polarity interaction cannot solely be due to long-term lexical associations. Additional predictability manipulations allowed us to also rule out an explanatory account that attributes the missing truth-value effect for negative sentences to low predictability. We also discuss the viability of an informativeness account.

Emotional responses to irony and emoticons in written language: Evidence from EDA and facial EMG.

While the basic nature of irony is saying one thing and communicating the opposite, it may also serve additional social and emotional functions, such as projecting humor or anger. Emoticons often accompany irony in computer-mediated communication, and have been suggested to increase enjoyment of communication. In the current study, we aimed to examine online emotional responses to ironic versus literal comments, and the influence of emoticons on this process. Participants read stories with a final comment that was either ironic or literal, praising or critical, and with or without an emoticon. We used psychophysiological measures to capture immediate emotional responses: electrodermal activity to directly measure arousal and facial electromyography to detect muscle movements indicative of emotional expressions. Results showed higher arousal, reduced frowning, and enhanced smiling for messages with rather than without an emoticon, suggesting that emoticons increase positive emotions. A tendency toward less negative responses (i.e., reduced frowning and enhanced smiling) for ironic than literal criticism, and less positive responses (i.e., enhanced frowning and reduced smiling) for ironic than literal praise suggests that irony weakens the emotional impact of a message. The present findings indicate the utility of a psychophysiological approach in studying online emotional responses to written language.

Online processing of moral transgressions: ERP evidence for spontaneous evaluation.

Experimental studies using fictional moral dilemmas indicate that both automatic emotional processes and controlled cognitive processes contribute to moral judgments. However, not much is known about how people process socio-normative violations that are more common to their everyday life nor the time-course of these processes. Thus, we recorded participants' electrical brain activity while they were reading vignettes that either contained morally acceptable vs unacceptable information or text materials that contained information which was either consistent or inconsistent with their general world knowledge. A first event-related brain potential (ERP) positivity peaking at ∼200 ms after critical word onset (P200) was larger when this word involved a socio-normative or knowledge-based violation. Subsequently, knowledge-inconsistent words triggered a larger centroparietal ERP negativity at ∼320 ms (N400), indicating an influence on meaning construction. In contrast, a larger ERP positivity (larger late positivity), which also started at ∼320 ms after critical word onset, was elicited by morally unacceptable compared with acceptable words. We take this ERP positivity to reflect an implicit evaluative (good-bad) categorization process that is engaged during the online processing of moral transgressions.

The on-line processing of socio-emotional information in prototypical scenarios: inferences from brain potentials.

Little is known about the time course of the mechanisms involved in the on-line processing of socio-emotional information. We used event-related brain potentials (ERPs) to investigate this issue using vignettes that described prototypical, social scenarios. An initial sentence established the social context and the following target sentence ended with a critical word that informed the reader of the character's socio-emotional response to the situation. Critical words that mismatched rather than matched with a character's expected feelings elicited a larger ERP negativity (N400) ~200-500 ms after word onset, followed by a larger frontal positivity. Dipole source modeling results indicated that an anterior temporal lobe source accounted for the N400-like effect, which we attribute to the increased demands of integrating general knowledge about social situations (e.g. scripts) with personal- and context-specific information. An additional mediofrontal source contributed to the later ERP effect and presumably reflects high-level mindreading functions. Together, these findings indicate that readers rapidly infer and evaluate on-line a character's likely socio-emotional response based on the prototypical information provided by the text.

Task-set reconfiguration and perceptual processing: behavioral and electrophysiological evidence.

Oriet and Jolicœur (2003) proposed that an endogenous task-set reconfiguration process acts as a hard bottleneck during which even early perceptual processing is impossible. We examined this assumption using a psychophysiological approach. Participants were required to switch between magnitude and parity judgment tasks within a predictable task sequence while event-related potentials (ERPs) were recorded. Stimulus contrast and response stimulus interval (RSI) were manipulated. Behavioral data demonstrated typical task switch costs that decreased as RSI increased. However, whereas ERP analysis of visual ERP component latencies sensitively revealed the contrast effect, a switch-specific postponement of perceptual processing during task-set reconfiguration at short RSIs was not observed. The present findings indicate that the process of task-set reconfiguration does not constitute a hard bottleneck that delays perceptual processing.