Conflict detection and base-rate extremity.

People tend to ignore the probabilistic rules cued by the base-rate information and rely on the heuristic intuition cued by the descriptive information to make "stereotypical" responses in base-rate problems. Conflict detection studies have shown that reasoners can detect conflicts between heuristic intuition and probabilistic considerations despite ultimately stereotypical responses. However, these studies primarily used extreme base-rate tasks. A critical open question is the extent to which successful conflict detection relies on an extreme base rate. The present study explores this issue by manipulating the base-rate extremity of problems in which the descriptive information and the base-rate information conflict or not. As a result, when reasoners made stereotypical responses in the conflict version of the moderate base-rate task, they took longer to respond, had lower confidence in their responses, and were slower to evaluate their confidence than in the no-conflict version of the task. All three measures indicate that stereotypical reasoners can stably detect conflict in moderate base-rate tasks, which expands the scope of successful conflict detection. Moreover, our response confidence data found a larger detection effect size in the extreme base-rate condition than in the moderate base-rate condition. This suggests that conflict detection is more efficient as the base-rate extremity increases. Implications for the boundary conditions of conflict detection are discussed.

Conflict Detection in Moderate Base-Rate Tasks: A Multi-Measure Study.

Empirical studies have found that although humans often rely on heuristic intuition to make stereotypical judgments during extreme base-rate tasks, they can at least detect conflicts between stereotypical and base-rate responses, which supports the dual-processing view of flawless conflict detection. The current study combines the conflict detection paradigm with moderate base-rate tasks of different scales to test the generalization and boundaries of flawless conflict detection. After controlling for possible confounding by the "storage failure" factor, the conflict detection results indicated that reasoners providing stereotypical heuristic responses to conflict problems were slower to respond, less confident in their stereotypical responses, and slower to indicate their reduced confidence than reasoners who answered no-conflict problems. Moreover, none of these differences were affected by different scales. The results suggest that stereotypical reasoners are not blind heuristic performers and that they at least realize that their heuristic responses are not entirely warranted, which supports the argument for flawless conflict detection and extends the boundaries of flawless conflict detection. We discuss the implications of these findings for views of detection, human rationality, and the boundaries of conflict detection.

Unconditional Perseveration of the Short-Term Mental Set in Chunk Decomposition.

A mental set generally refers to the brain's tendency to stick with the most familiar solution to a problem and stubbornly ignore alternatives. This tendency is likely driven by previous knowledge (the long-term mental set) or is a temporary by-product of procedural learning (the short-term mental set). A similar problem situation is considered the factor required for perseveration of the long-term mental set, which may not be essential for the short-term mental set. To reveal the boundary conditions for perseveration of the short-term mental set, this study adopted a Chinese character decomposition task. Participants were asked to perform a practice problem that could be solved by a familiar loose chunk decomposition (loose solution) followed by a test problem, or they were asked to repeatedly perform 5-8practice problems followed by a test problem; the former is the base-set condition, and the latter is the enhanced-set condition. In Experiment 1, the test problem situation appeared to be similar to the practice problem and could be solved using the reinforced loose solution and also an unfamiliar tight chunk decomposition (tight solution) (a 2-solution problem). In Experiment 2, the test problem situation differed from the practice problem and could only be solved using an unfamiliar tight solution (a 1-solution problem). The results showed that, when comparing the enhanced-set and base-set conditions, both the accuracy rate and the response times for solving the test problem with a tight solution were worse in Experiment 1, whereas the response times were worse in Experiment 2. We concluded that perseveration of the short-term mental set was independent of the similarity between problem situations and discuss the differences in perseveration between two types of fixation.

The Effect of Aging on the Dynamics of Reactive and Proactive Cognitive Control of Response Interference.

A prime-target interference task was used to investigate the effects of cognitive aging on reactive and proactive control after eliminating frequency confounds and feature repetitions from the cognitive control measures. We used distributional analyses to explore the dynamics of the two control functions by distinguishing the strength of incorrect response capture and the efficiency of suppression control. For reactive control, within-trial conflict control and between-trial conflict adaption were analyzed. The statistical analysis showed that there were no reliable between-trial conflict adaption effects for either young or older adults. For within-trial conflict control, the results revealed that older adults showed larger interference effects on mean RT and mean accuracy. Distributional analyses showed that the decline mainly stemmed from inefficient suppression rather than from stronger incorrect responses. For proactive control, older adults showed comparable proactive conflict resolution to young adults on mean RT and mean accuracy. Distributional analyses showed that older adults were as effective as younger adults in adjusting their responses based on congruency proportion information to minimize automatic response capture and actively suppress the direct response activation. The results suggest that older adults were less proficient at suppressing interference after conflict was detected but can anticipate and prevent inference in response to congruency proportion manipulation. These results challenge earlier views that older adults have selective deficits in proactive control but intact reactive control.

Inhibition dysfunction in depression: event-related potentials during negative affective priming.

The study aimed to investigate whether depressed patients show impairment of valence-dependent inhibition and its neurophysiological correlates. Event-related potentials (ERPs) were collected from 18 patients with unipolar depression and 18 normal controls during an affective negative priming task. A less effective inhibition in patients was specific for negative information. These behavioral effects were paralleled by ERP differences. In addition to the overall reduced P2 amplitude for negative trials and the overall reduced late positive component (LPC) amplitude for positive and negative trials in patients, ERP differences in different conditions for each group were also found. The patients showed reduced central-parietal P2 amplitude and shorter LPC latency in response to negative experimental targets, whereas the controls showed larger left central P2 amplitude and delayed LPC latency in response to negative experimental targets. No such effects were found for positive targets. These results suggest that the inhibition dysfunction of negative affect influences the earlier attention allocation stage and the later evaluation stage in depressed patients.