Positive affect facilitates task switching in the dimensional change card sort task: Implications for the shifting aspect of executive function

Using the modified Dimensional Change Card Sort task, we examined the influence of positive affect on task switching by inspecting various markers for the costs, including restart cost, switch cost and mixing cost. Given that the executive-control processes that underlie switching performance—i.e., inhibition or shifting—are distinct from the component processes that underlie non-switching performance—i.e., stimulus evaluation, resource allocation or response execution—we hypothesised that if positive affect facilitates task switching via executive-control processes, rather than via component processes, positive affect would reduce both switch and restart costs, but not mixing cost, because both switch and restart costs rely on executive processes, while mixing cost imposes only minimal demands on executive processes. We found beneficial effects of positive affect on both restart and switch costs, but not on mixing costs. These results suggest that positive affect improves switching abilities via executive processes rather than via component processes.     

Task conflict,information processing,and decision-making: The damaging effect of relationship conflict

A popular theoretical assumption holds that task-related disagreements stimulate critical thinking, and thus may improve group decision making. Two recent meta-analyses showed, however, that task conflict can have a positive effect, a negative effect, or no effect at all on decision-making quality (De Dreu & Weingart, 2003; De Wit, Greer, & Jehn, 2012). In two studies, we built upon the suggestion of both meta-analyses that the presence of relationship conflict determines whether a task conflict is positively or negatively related to decision making. We hypothesized and found that the level of perceived relationship conflict during task conflict (Study 1), and the actual presence (vs. absence) of relationship conflict during task conflict (Study 2), increased group members’ rigidity in holding onto suboptimal initial preferences during decision making and thus led to poor decisions. In both studies the effect of relationship conflict on decision making was mediated by biased use of information.     

Developmental changes of win-stay and loss-shift strategies in decision making

This study aims to clarify the developmental changes in real-life decision making when strategy is adjusted using both positive and negative feedback, that is, whether strategic adjustment evolves with age. A total of 84 participants divided into three age groups (children, adolescents, and adults) performed the standard version of the Iowa Gambling Task (IGT). Children and adolescents showed a strong bias in favor of disadvantageous choices whereas adults learned to decide advantageously during the course of the task. Interestingly, the results clearly demonstrate that children did not switch differently following gains and losses whereas adolescents and adults switched more often after a loss than after a gain, corresponding to the “loss-shift” and the “win-stay” strategies, respectively. The results also revealed that adults switched less often after losses compared to children and adolescents and, thus, used the loss-stay strategy more often than the 2 youngest groups. These new findings suggest that successful completion of the IGT by adults requires fine feedback monitoring and more frequent use of the win-stay and loss-stay strategic adjustments.     

Differential attentional allocation and subsequent recognition for young and older adult faces

Studies examining own-age recognition biases report inconsistent results and often utilize paradigms that present faces individually and in isolation. We investigated young and older adults' attention towards young and older faces during learning and whether differential attention influences recognition. Participants viewed complex scenes while their eye movements were recorded; each scene contained two young and two older faces. Half of the participants formed scene impressions and half prepared for a memory test. Participants then completed an old/new face recognition task. Both age groups looked longer at young than older faces; however, only young adults showed an own-age recognition advantage. Participants in the memory condition looked longer at faces but did not show enhanced recognition relative to the impressions condition. Overall, attention during learning did not influence recognition. Our results provide evidence for a young adult face bias in attentional allocation but suggest that longer looking does not necessarily indicate deeper encoding.     

Temporal cue–target overlap is not essential for backward inhibition in task switching

Lag 2 repetition costs are a performance cost observed when participants return to a task after just one intervening trial of a different task, compared to returning after a longer interval (AB A vs. CB A sequences, where A, B, C are tasks). This effect is known as backward inhibition (BI) and is thought to reflect the need to overcome inhibition applied specifically to Task “A” during disengagement at trial n – 1. Druey and Hübner (2007) Druey, M. and Hübner, R. 2007. The role of temporal cue–target overlap in backward inhibition under task switching. Psychonomic Bulletin & Review, 14: 749–754. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar] have suggested that employment of such a specific inhibitory mechanism relies upon the cue and the target of the task overlapping temporally. We provide evidence across three experiments (including a direct replication attempt) that this is not the case, and that the presence of task-specific BI relies to some extent on the need to translate the cue–target relationship into working memory. Additionally, we provide evidence that faster responses in no overlap conditions are driven by low-level perceptual differences between target displays across overlap conditions. We conclude that BI is an effective sequential control mechanism, employed equally in cases of temporally overlapping and temporally separated cues and targets.     

Selective impairment of masked priming in dual-task performance

This study investigated the impact of divided attention on masked priming. In a dual-task setting, two tasks had to be carried out in close temporal succession: a tone discrimination task and a masked priming task. The order of the tasks was varied between experiments, and attention was always allocated to the first task—that is, the first task was prioritized. The priming task was the second (nonprioritized) task in Experiment 1 and the first (prioritized) task in Experiment 2. In both experiments, “novel” prime stimuli associated with semantic processing were essentially ineffective. However, there was intact priming by another type of prime stimuli associated with response priming. Experiment 3 showed that all these prime stimuli can reveal significant priming effects during a task-switching paradigm in which both tasks were performed consecutively. We conclude that dual-task specific interference processes (e.g., the simultaneous coordination of multiple stimulus–response rules) selectively impair priming that is assumed to rely on semantic processing.     

Between-task competition for intentions and actions

People can switch quickly and flexibly from one task to another, but suffer the effects of between-task competition when they do so: After switching, they tend to be distracted by irrelevant stimulus information and hampered by incorrect actions associated with recently performed tasks. This competition results in performance costs of switching, as well as a bias against switching when there is choice over which task to perform, particularly when switching from a difficult task to an easier one. Two experiments investigated the locus of these between-task competition effects in voluntary task switching. Participants switched between an easy location classification and a harder shape classification, making two responses on each trial: the first to register their task choice, the second to perform the chosen task on a subsequently presented stimulus. The results indicated that participants chose to perform the difficult shape task more often than the easier location task, evidence that between-task competition affects intentions that are expressed independently of task-specific actions. The bias was stronger in participants with faster choice speed, suggesting that these influences are relatively automatic. Moreover, even though participants had unlimited time to choose and prepare a task before stimulus presentation, their subsequent performance was nonetheless sensitive to persisting effects of between-task competition. Altogether these results indicate the pervasive influence of between-task competition, which affects both the expression of global task intentions and the production of task-specific actions.     

Control processes in voluntary and explicitly cued task switching

Explicitly cued task switching slows performance relative to performing the same task on consecutive trials. This effect appears to be due partly to more efficient encoding of the task cue when the same cue is used on consecutive trials and partly to an additional task-switching process. These components were examined by comparing explicitly cued and voluntary task switching groups, with external cues presented to both groups. Cue-switch effects varied in predictable ways to dissociate explicitly cued and voluntary task switching, whereas task-switch effects had similar characteristics for both instructional groups. The data were well fitted by a mathematical model of task switching that included a cue-encoding mechanism (whereby cue repetition improves performance) and an additional process that was invoked on task-switch trials. Analyses of response-time distributions suggest that this additional process involves task-set reconfiguration that may or may not be engaged before the target stimulus is presented.     

Attention and action: The role of response mappings in auditory attention switching

Switching auditory attention incurs a performance decrement (i.e. auditory attention-switch costs). Using an auditory attention-switching paradigm, we aimed to generalise these across different response mappings. In all three experiments, two number words, spoken by a female and male speaker, were presented dichotically via headphones. A visual cue indicated the gender of the to-be-attended speaker in each trial. The task was a magnitude judgement of the relevant number word (i.e. smaller vs. larger than 5). We additionally varied the interval between cue onset and auditory stimulus onset (cue-stimulus interval) to explore cue-based preparatory effects. In Experiment 1, attention switching was more costly with direct-verbal responses (e.g. ‘smaller’) than in the shadowing task (e.g. ‘three’). In Experiment 2, performance was largely similar for direct-verbal responses and abstract-verbal responses (e.g. ‘left’). In Experiment 3, performance was generally worse with abstract-verbal responses than with abstract-manual responses (e.g. left key press) and auditory attention-switch costs were similar for both response mappings. Overall, auditory switch costs occurred more or less invariably across response mappings in categorical (magnitude) judgements suggesting a minor role of the response mapping in auditory attention switching. Furthermore, verbal identity-based judgements (i.e. shadowing) generally seem to benefit from ideomotor compatibility.