Modeling cognitive control in task-switching

This article describes a quantitative model, which suggests what the underlying mechanisms of cognitive control in a particular task-switching paradigm are, with relevance to task-switching performance in general. It is suggested that participants dynamically control response accuracy by selective attention, in the particular paradigm being used, by controlling stimulus representation. They are less efficient in dynamically controlling response representation. The model fits reasonably well the pattern of reaction time results concerning task switching, congruency, cue-target interval and response-repetition in a mixed task condition, as well as the differences between mixed task and pure task conditions. Received: 31 March 1999 / Accepted: 23 July 1999     

Consciousness and cognitive control

The implementation or change of information processing routines, known as cognitive control, is traditionally believed to be closely linked to consciousness. It seems that we exert control over our behavior if we know the reasons for, and consequences of, doing so. Recent research suggests, however, that several behavioral phenomena that have been construed as instances of cognitive control can be prompted by events of which actors are not aware. Here we give a brief review of this research, discuss possible reasons for inconsistencies in the empirical evidence, and suggest some lines of future research. Specifically, we suggest to differentiate cognitive control evoked either because of explicit or because of implicit control cues. While the former type of control seems to work outside of awareness, the latter type of control seems to be restricted to consciously registered events that call for control.     

Reduced cognitive control in passionate lovers

Passionate love is associated with intense changes in emotion and attention which are thought to play an important role in the early stages of romantic relationship formation. Although passionate love usually involves enhanced, near-obsessive attention to the beloved, anecdotal evidence suggest that the lover’s concentration for daily tasks like study and work may actually be impaired, suggesting reduced cognitive control. Affect might also contribute to changes in cognitive control. We examined the link between passionate love and cognitive control in a sample of students who had recently become involved in a romantic relationship. Intensity of passionate love as measured by the Passionate Love Scale was shown to correlate with decreased individual efficiency in cognitive control as measured in Stroop and flanker task performance. There was no evidence that affective changes mediate this effect. This study provides the first empirical evidence that passionate love in the early stages of romantic relationship is characterized by impaired cognitive control.     

Contextual adjustments in cognitive control across tasks

Does encountering information-processing conflict recruit general mechanisms of cognitive control or change only the representations of specific cues and responses? In the present experiments, a flanker task elicited responses to symbolic information (arrow meaning), whereas Stroop-like tasks elicited responses to nonsymbolic information (color of a letter or location of a target box). Despite these differences, when participants performed the flanker and Stroop tasks intermittently in randomized orders, the extent of information-processing conflict encountered on a particular trial modulated performance on the following trial. On across-task trial pairs, increases in response time to incongruent relative to congruent stimulus arrays were smaller immediately following incongruent trials than immediately following congruent trials. The degree of cognitive control exerted on a particular task thus appears to reflect not only the quality, but also the quantity, of recent experiences of information-processing conflict.     

The cognitive control of emotion

The capacity to control emotion is important for human adaptation. Questions about the neural bases of emotion regulation have recently taken on new importance, as functional imaging studies in humans have permitted direct investigation of control strategies that draw upon higher cognitive processes difficult to study in nonhumans. Such studies have examined (1) controlling attention to, and (2) cognitively changing the meaning of, emotionally evocative stimuli. These two forms of emotion regulation depend upon interactions between prefrontal and cingulate control systems and cortical and subcortical emotion-generative systems. Taken together, the results suggest a functional architecture for the cognitive control of emotion that dovetails with findings from other human and nonhuman research on emotion.     

Conflict monitoring and cognitive control

A neglected question regarding cognitive control is how control processes might detect situations calling for their involvement. The authors propose here that the demand for control may be evaluated in part by monitoring for conflicts in information processing. This hypothesis is supported by data concerning the anterior cingulate cortex, a brain area involved in cognitive control, which also appears to respond to the occurrence of conflict. The present article reports two computational modeling studies, serving to articulate the conflict monitoring hypothesis and examine its implications. The first study tests the sufficiency of the hypothesis to account for brain activation data, applying a measure of conflict to existing models of tasks shown to engage the anterior cingulate. The second study implements a feedback loop connecting conflict monitoring to cognitive control, using this to simulate a number of important behavioral phenomena.     

Blinking predicts enhanced cognitive control

Recent models have suggested an important role for neuromodulation in explaining trial-to-trial adaptations in cognitive control. The adaptation-by-binding model (Verguts & Notebaert, Psychological review, 115(2), 518–525, 2008), for instance, suggests that increased cognitive control in response to conflict (e.g., incongruent flanker stimulus) is the result of stronger binding of stimulus, action, and context representations, mediated by neuromodulators like dopamine (DA) and/or norepinephrine (NE). We presented a flanker task and used the Gratton effect (smaller congruency effect following incongruent trials) as an index of cognitive control. We investigated the Gratton effect in relation to eye blinks (DA related) and pupil dilation (NE related). The results for pupil dilation were not unequivocal, but eye blinks clearly modulated the Gratton effect: The Gratton effect was enhanced after a blink trial, relative to after a no-blink trial, even when controlling for correlated variables. The latter suggests an important role for DA in cognitive control on a trial-to-trial basis.     

Age-related qualitative differences in post-error cognitive control adjustments

Detecting an error signals the need for increased cognitive control and behavioural adjustments. Considerable development in performance monitoring and cognitive control is evidenced by lower error rates and faster response times in multi-trial executive function tasks with age. Besides these quantitative changes, we were interested in whether qualitative changes in balancing accuracy and speed contribute to developmental progression during elementary school years. We conducted two studies investigating the temporal and developmental trajectories of post-error slowing in three prominent cognitive conflict tasks (Stroop, Simon, and flanker). We instructed children (8-, 10-, and 12-year-old) and adults to respond as fast and as accurately as possible and measured their response times on four trials after correct and incorrect responses to a cognitive conflict. Results revealed that all age groups had longer response times on post-error versus post-correct trials, reflecting post-error slowing. Critically, slowing on the first post-error trial declined with age, suggesting an age-related reduction in the orienting response towards errors. This age effect diminished on subsequent trials, suggesting more fine-tuned cognitive control adjustments with age. Overall, the consistent pattern across tasks suggests an age-related change from a relatively strong orienting response to more balanced cognitive control adaptations.     

Executive control of cognitive processes in task switching

In 4 experiments, participants alternated between different tasks or performed the same task repeatedly. The tasks for 2 of the experiments required responding to geometric objects in terms of alternative classification rules, and the tasks for the other 2 experiments required solving arithmetic problems in terms of alternative numerical operations. Performance was measured as a function of whether the tasks were familiar or unfamiliar, the rules were simple or complex, and visual cues were present or absent about which tasks should be performed. Task alternation yielded switching-time costs that increased with rule complexity but decreased with task cuing. These factor effects were additive, supporting a model of executive control that has goal-shifting and rule-activation stages for task switching. It appears that rule activation takes more time for switching from familiar to unfamiliar tasks than for switching in the opposite direction.     

Within-session practice eliminates age differences in cognitive control

ABSTRACT

Previous research employing short-term practice and long-term training have been successful in reducing cognitive control deficits in the elderly. The goal of this study was to examine the effect of practice within session on a demanding cognitive control task. Nineteen older adults and 16 young adults performed 720 trials of a cued version of the Stroop task, in which an instructional cue is presented before each individually presented Stroop stimulus. Statistical analyses focused on the most difficult color-naming condition in task-switching blocks. Overall, participants showed faster reaction times and decreased errors with practice, particularly on incongruent trials. Older adults showed a greater reduction in errors with practice than young adults. Moreover, older adults, but not young adults, showed a reduction in errors and reaction times with practice on incongruent trials. Findings further suggest that practice reduces age-related differences in cognitive control. Improvements in cognitive control functioning has implications for treating functional deficits in older adults.     

Cross-linguistic phonotactic competition and cognitive control in bilinguals

The current study examines the relation between cognitive control and linguistic competition resolution at the sublexical level in bilinguals. Twenty-one Spanish–English bilinguals and 23 English monolinguals completed a non-linguistic Stroop task (indexing inhibitory control) and a linguistic priming/lexical decision task (indexing Spanish phonotactic-constraint competition during English comprehension). More efficient Stroop performance (i.e. a smaller Stroop effect) in bilinguals was associated with decreased competition from Spanish phonotactic constraints during English comprehension. This relation was observed when nonword targets overlapped in phonotactic constraints and phonological form with preceding cognate primes (e.g. prime: stable (Spanish: estable)/target: esteriors). Findings suggest a link between non-linguistic cognitive control and co-activation of linguistic structures at the sublexical level in bilinguals.     

认知控制在第三方惩罚中的作用

第三方惩罚是一种特殊的利他行为, 在维护社会规范和人类合作中发挥着重要作用。现有研究对遵守社会规范行为及其认知机制进行了大量探讨, 而第三方惩罚这一维护社会规范行为的认知加工过程, 尤其是认知控制在其中发挥的具体作用, 是目前研究的热点之一。通过(1)借助不同技术方法来探究认知控制在第三方惩罚中的具体作用; (2)从发展的视角, 在认知控制发展的关键阶段来考察其作用随年龄的发展变化, 用以解释第三方惩罚这一利他行为的发展轨迹, 完善对第三方惩罚的认知基础的理解, 并构建第三方惩罚决策的心理模型。     

Modelling cognitive control in task switching and ageing

In an attempt to better understand the reasons for old-age effects on task switching performance, we fitted a quantitative model (Meiran, 2000a) to results from an experiment comparing young and elderly participants. Modelling results indicate that the most pronounced effect of old age was in what can be broadly defined as the duration of the response selection. In addition, compared to young participants, the elderly tended to rely on learning from the preceding trial, which improved their performance in single-task conditions but impaired it when the tasks switched frequently. Relatively modest effects of old age were found in the ability to selectively attend to the task relevant stimulus dimension and on the duration of processing stages preceding or following response selection.     

认知控制在发散性思维中的作用

探讨认知控制在发散性思维中的作用是当前创造力研究领域的热点问题。目前一致认为认知控制包括工作记忆、抑制控制和认知灵活性三个核心成分。工作记忆对个体在发散性思维中维持任务目标、提取和操作信息发挥重要作用; 抑制控制, 包括优势反应抑制、分心干扰抑制和对潜在相关信息的低抑制, 分别压制对常规观点的提取、确保对内在注意状态的维持和提供更多观念的组合, 进而促进个体的发散性思维表现。此外, 流体智力作为一种高级认知控制能力, 可通过增强策略使用的灵活性从而利于发散性思维。近来神经科学研究表明, 发散性思维不同阶段需要执行控制网络和默认网络的动态协同加工。未来研究应澄清认知控制各子成分间的关系, 探讨认知控制影响发散性思维是否受到其他因素(如动机和情绪)的调节, 以及探索执行控制网络和默认网络的动态协作是否受到任务要求和个体差异(如人格和智力)的影响。