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Under time pressure, it is usually not possible to respond quickly and accurately at the same time. Therefore, people must trade speed for accuracy, depending on the current payoff conditions. Ideally, they should choose a speed-accuracy tradeoff (SAT) that optimizes their monetary reward. However, this is hardly the case. Rather, persons exhibit an accuracy bias, which is often disadvantageous. To further investigate the role of errors for optimizing reward, we conducted a flanker-task study with different payoff and framing conditions. Whereas the reward for correct responses always increased continuously with speed, the costs of errors varied. In three of four conditions, responding very fast, even with low accuracy, was favorable. Furthermore, in addition to the usual gain framing, half of our participants were instructed according to a loss frame. Whereas framing had little effect on performance, we found a substantial accuracy bias. Only in the most extreme condition some participants overcame their bias and responded very quickly. To examine how SAT strategies differed between participants, we modeled the performance with a sequential-sampling model. The results suggest that various mechanisms were involved in realizing specific SATs. However, they were hardly applied to optimize reward. Rather, participants seem to have optimized their well-being. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Every day, we are confronted with a vast amount of information that all competes for our attention. Some of this information might be associated with rewards (e.g., gambling) or losses (e.g., insurances). To what extent such information, even if irrelevant for our current task, not only attracts attention but also affects our actions is still a topic under examination. To address this issue, we applied a new experimental paradigm that combines visual search and a spatial compatibility task. Although colored stimuli did not modulate the spatial compatibility effect more than gray stimuli, we found clear evidence that reward and loss associations attenuated this effect, presumably by affecting attention and response selection. Moreover, there are hints that differences in these associations are also reflected in a modulation of the spatial compatibility effect. We discuss theoretical implications of our results with respect to the influences of color, reward, and loss association on selective attention and response selection.

Working memory (WM) holds and manipulates representations for ongoing cognition. Oberauer (Psychology of Learning and Motivation, 51, 45–100, 2009) distinguishes between two analogous WM sub-systems: a declarative WM which handles the objects of thought, and a procedural WM which handles the representations of (cognitive) actions. Here, we assessed whether analogous effects are observed when participants switch between memory sets (declarative representations) and when they switch between task sets (procedural representations). One mechanism assumed to facilitate switching in procedural WM is the inhibition of previously used, but currently irrelevant task sets, as indexed by n-2 task-repetition costs (Mayr & Keele, Journal of Experimental Psychology: General, 129(1), 4–26, 2000). In this study we tested for an analogous effect in declarative WM. We assessed the evidence for n-2 list-repetition costs across eight experiments in which participants switched between memory lists to perform speeded classifications, mental arithmetic, or a local recognition test. N-2 list-repetition costs were obtained consistently in conditions assumed to increase interference between memory lists, and when lists formed chunks in long-term memory. Further analyses across experiments revealed a substantial contribution of episodic memory to n-2 list-repetition costs, thereby questioning the interpretation of n-2 repetition costs as reflecting inhibition. We reanalyzed the data of eight task-switching experiments, and observed that episodic memory also contributes to n-2 task-repetition costs. Taken together, these results show analogous processing principles in declarative and procedural WM, and question the relevance of inhibitory processes for efficient switching between mental sets.

Switching between mental sets has been extensively investigated in both experimental and individual differences research using a wide range of task-switch paradigms. However, it is yet unclear whether these different tasks measure a unitary shifting ability or reflect different facets thereof. In this study, 20 task pairs were administered to 119 young adults to assess 5 proposed components of mental set shifting: switching between judgments, stimulus dimensions, stimulus-response mappings, response sets, and stimulus sets. Modeling latent factors for each of the components revealed that a model with 5 separate yet mostly correlated factors fit the data best. In this model, the components most strongly related to the other latent factors were stimulus-response mapping shifting and, to a lesser degree, response set shifting. In addition, both factors were statistically indistinguishable from a second-order general shifting factor. In contrast, shifting between judgments as well as stimulus dimensions consistently required separate factors and could, hence, not fully be accounted for by the general shifting factor. Finally, shifting between stimulus sets was unrelated to any other shifting component but mapping shifting. We conclude that tasks assessing shifting between mappings are most adequate to assess general shifting ability. In contrast, shifting between stimulus sets (e.g., as in the Trail Making Test) probably reflects shifts in visual attention rather than executive shifting ability. (PsycINFO Database Record

The article investigates the mechanisms of selecting and updating representations in declarative and procedural working memory (WM). Declarative WM holds the objects of thought available, whereas procedural WM holds representations of what to do with these objects. Both systems consist of three embedded components: activated long-term memory, a central capacity-limited component for building structures through temporary bindings, and a single-element focus of attention. Five experiments test the hypothesis of analogous mechanisms in declarative and procedural WM, investigating repetition effects across trials for individual representations (objects and responses) and for sets (memory sets and task sets), as well as set-congruency effects. Evidence for analogous processes was obtained from three phenomena: (1) Costs of task switching and of list switching are reduced with longer preparation interval. (2) The effects of task congruency and of list congruency are undiminished with longer preparation interval. (3) Response repetition interacts with task repetition in procedural WM; here we show an analogous interaction of list repetition with item repetition in declarative WM. All three patterns were reproduced by a connectionist model implementing the assumed selection and updating mechanisms. The model consists of two modules, an item-selection module selecting individual items from a memory set, or responses from a task set, and a set-selection module for selecting memory sets or task sets. The model codes the matrix of binding weights in the item-selection module as a pattern of activation in the set-selection module, thereby providing a mechanism for building chunks in LTM, and for unpacking them as structures into working memory.

The article investigates the relation between declarative and procedural working memory (WM; Oberauer 2009). Two experiments test the assumption that representations in the two subsystems are selected for processing in analogous ways. Participants carried out a series of decisions on memorized lists of digits. For each decision they had to select declarative and procedural representations. Regarding declarative representations participants selected a memory set and a digit within this set as the input to each decision. With respect to the procedural representations they selected a task set to be applied to the selected digit and a response within that task set. We independently manipulated the number of lists and the number of tasks to be switched among (one two or three; Experiment 1) and preparation time for a list switch (Experiment 2). For three effects commonly observed in taskswitch studies analogues in declarative WM were found: list switch costs mixing costs and residual switch costs. List and task switch costs were underadditive suggesting that declarative and procedural representations are selected separately and in parallel. The findings support the hypothesis of two analogous WM subsystems. Keywords: Working memory; Task switching.

The coding of stimuli and responses is crucial for human behaviour. Here, we focused primarily on the response codes (or response categories). As a method, we applied a combined dual-task and task-switch paradigm with a fixed task-to-hand mapping. Usually, negative effects (i.e., costs) are observed for response category repetitions under task switching. However, in several previous studies it has been proposed that such repetition effects do not occur, if the stimulus categories (e.g., “odd” if digits have to be classified according to their parity feature) are unequivocally mapped to specific responses. Our aim was to test this hypothesis. In the present experiments, we were able to distinguish between three different types of possible response codes. The results show that the participants generally code their responses according to abstract response features (left/right, or index/middle finger). Moreover, the spatial codes were preferred over the finger-type codes even if the instructions stressed the latter. This preference, though, seemed to result from a stimulus–response feature overlap, so that the spatial response categories were primed by the respective stimulus features. If there was no such overlap, the instructions determined which type of response code was involved in response selection and inhibition.

Under task switch conditions, response repetitions usually produce benefits if the task also repeats, but costs if the task switches. So far, it is largely undecided how to account for these effects. In the present study, we provide additional evidence in favor of the account that each response is inhibited in order to prevent its accidental re-execution. To test this hypothesis, the risk of an accidental re-execution of a given response was manipulated by modulating the activation of the response in the previous task. In Experiment 1, this was done by means of congruent and incongruent stimuli. As expected, on task switch trials, the repetition costs were larger if a congruent rather than an incongruent stimulus occurred in the previous task. In Experiment 2, the same effect occurred for stimulus-response compatible versus incompatible stimuli in the previous task. In Experiment 3, both manipulations were applied together, which produced almost additive effects. Altogether, the results support the inhibition account for the response repetition effects under task switch conditions.

Repetition effects are often helpful in revealing information about mental structures and processes. Usually, positive effects have been observed when the stimuli or responses are repeated. However, in task shift studies it has also been found that response repetitions can produce negative effects if the task shifts. Although several mechanisms have been proposed to account for this interaction between task shifting and response repetition, many details remain open. Therefore, a series of four experiments was conducted to answer two questions. First, are motor responses necessary to produce response-related repetition effects, or is response activation sufficient? Second, does the risk of an accidental re-execution of the last response affect the repetition costs? The results show that response activation alone can produce repetition effects. Furthermore, the risk of accidental response re-execution largely modulates these effects.

We investigate interference between declarative and procedural representations in working memory (WM). Declarative representations are objects of thought, whereas procedural representations provide the (cognitive) actions to work upon these objects. In eight dual-task experiments we varied the number of representations to be maintained in WM (memory load). In Experiments 1–4, we varied declarative and procedural load separately in the two tasks used. In Experiments 5–8, only declarative or procedural load was manipulated in both tasks employed. We measured how much performance in the currently relevant task was impaired by increasing the load in the currently irrelevant task. These cross-task load effects were larger for Experiment 5–8 compared to Experiment 1–4. Yet, in task-switch trials we also obtained cross-task load effects in Experiment 1–4. Our findings support the distinction of declarative and procedural WM as largely independent sub-systems or distinct representational spaces.

Repetition effects are often viewed as informative regarding the cognitive mechanisms of action control. One particular finding, namely costs for repeating the same response in subsequent trials, especially challenges theorizing. Costs for response repetitions have recently been reported in task-switch studies on task-switch trials (whereas benefits usually arise in task-repetition trials), but also in some choice-RT task studies. In three experiments, two of the most successful accounts for the response-repetition costs in choice-RT task studies and task switching were tested: an expectancy-based explanation, and an inhibition-based account. Using a choice-RT task introduced by Smith (1968) and manipulating the response-stimulus interval (RSI) and the categorizability of the stimuli, some specific predictions of the two accounts were tested. The results clearly revealed that expectancy-based explanations fail to account for the observed patterns of effects, whereas they are well in line with the predictions from the inhibition-based account. Finally, the results are further discussed with respect to alternative accounts from the field of task switching.

Interestingness is said to be the power of attracting or holding one's attention (because something is unusual or exciting, etc.). We, as humans, have the great capacity to direct our visual attention and judge the interestingness of a scene. Consider for example the image sequence in the figure on the right. The spider in front of the camera or the snow on the lens are examples of events that deviate from the context since they violate the expectations, and therefore are considered interesting. On the other hand, weather changes or a camera shift, do not raise human attention considerably, even though large regions of the image are influenced. In this work we firstly investigate what humans consider as "interesting" in image sequences. Secondly we propose a computer vision algorithm to automatically spot these interesting events. To this end, we integrate multiple cues inspired by cognitive concepts and discuss why and to what extent the automatic discovery of visual interestingness is possible.

When rapidly switching between two tasks, bivalent stimuli can accidentally trigger the previously executed and therefore still activated response. Recently, it has been suggested that behavioral response-repetition effects reflect response inhibition that reduces the risk of such erroneous response repetitions. The present study investigated neural correlates of this inhibition process using lateralized readiness potentials (LRP). In three experiments, we demonstrate a response-switch bias emerging during the preparatory interval which is independent of task sequence (Experiment 1), which is linked to task preparation (Experiment 2), and which is present only under task-switching conditions (Experiment 3). These results suggest that the bias reflects a control process that adaptively regulates response preparedness.

Several task-switch studies show that response category repetition is favorable on task repetition trials, but disadvantageous on task switch trials. In the present study we investigated how this interaction depends on the type and number of involved response categories. In a dual-task number-categorization experiment, subjects had to respond to tasks T(1) and T(2) with one of the two fingers of their left and right hand, respectively. For one group of participants, the use of spatial response categories, and for another group the use of finger-type categories was induced. It turned out that the interaction between task switching and response category repetition was clearly related to the induced response categories, but at the same time, the spatial categories nevertheless also affected response selection in the finger-type group. However, these two effects were additive. This shows that multiple response codes can simultaneously be involved in response selection, but that they affect performance differentially.

One of the proposed mechanisms for sequential control in task-shift conditions is backward inhibition (BI), which is usually measured in terms of lag-2 task repetition costs in A-B-A task sequences relative to C-B-A task sequences. By considering the so far existing experiments it seems that these lag-2 repetition costs occur only with temporally overlapping cues and targets. In the present study this issue was further examined in two experiments, in which temporal cue-target overlap was varied blockwise (Experiment 1) and from trial-to-trial (Experiment 2). Experiment 1 shows that lag-2 repetition effects can only be observed with temporally overlapping cues and targets, indicating that there was no BI with temporally separated cues and targets. However, the results of Experiment 2 suggest that both irrelevant task sets are inhibited in this case, and that with temporally overlapping cues and targets only the previously relevant task set is inhibited.