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This study reports the results of 4 experiments that addressed whether the domains of deictic time and number exert a cross-domain link. Such a link would be consistent with A Theory of Magnitude (i.e., ATOM). In contrast, no link between the two domains would support the conceptual metaphor theory (CMT), which assumes that each domain is only linked to space. In Experiment 1, participants made speeded decisions about temporal stimuli referring either to the past or to the future (e.g., tomorrow). In the spatial response condition, they vocally responded either with the word "left" or "right," whereas, in the number response condition, they responded with the word "1" or "9". A strong congruency effect was observed with spatial responses, but only a small one (in error rates) concerning number responses. In Experiment 2, the stimuli were the numbers 1 and 9. In the spatial response condition, participants responded again with the words "left" or "right," whereas, in the deictic time condition, they responded with "past" and "future." As before, a strong congruency effect was observed for the spatial condition; no or even a reversed congruency effect was obtained for the deictic time condition. Experiment 3 replicated this unexpected result, and Experiment 4 assessed whether this reversed congruency effect in the deictic time condition of Experiments 2 and 3 could be attributed to short versus long utterance duration. It is concluded that CMT provides the most parsimonious account for the obtained pattern of results, suggesting no direct link between deictic time and number processing.

Driving at an inappropriate speed is a major accident cause in the EU. Understanding the underlying sensory mechanisms can help to reduce speed and increase traffic safety. The present study investigated the effect of visuospatial stimuli on speed perception using an adaptive countermeasure to speeding based on a manipulation of optic flow. We added red lights on both sides of a simulated road. We expected speed to be perceived as faster when lights moved toward drivers due to increased optic flow, whereas we expected static light stimuli to not alter the optic flow and thus not influence speed perception. Two experiments applied the method of constant stimuli. To this end, participants encountered several trials of two video sequences on a straight road. A reference sequence showed the same traveling speed while test sequences varied around different traveling speeds. Participants indicated which sequence they perceived as faster, leading to the calculation of the point of subjective equality (PSE). A lower PSE indicates that the speed in this experimental condition is perceived as faster than in another experimental condition. Experiment 1A did not show a difference between PSEs of static and oncoming lights. Because participants had counted reflector posts for speed estimation, we removed these reflector posts in Experiment 1B and found a lower PSE for oncoming lights. Thus, such light stimuli may have an effect only in situations without other competing visual stimuli supporting speed perception. Future research should investigate whether speed perception is indeed a primarily visuospatial control task or whether other sensory information such as auditory factors can have an influence as well.

Studies of switching between tasks and studies of error commission have both provided solid behavioral measures of executive control. Nonetheless, a gap remains between these strands of research. In three experiments we sought to reduce this gap by assessing the impact of task errors on N-2 repetition costs, an effect supposedly related to task-set inhibition. Based on previous literature reporting a task-switch benefit following task errors, due to incidental learning of the erroneously executed task-set, we predicted N-2 repetition costs to be decreased after task errors in Trial N-2, relative to correct responses. Furthermore, we predicted this effect to be present only when corrective control mechanisms would not have the time to build up on the post-error trial (i.e., following fast post-error trial only). This hypothesis was tested in a three-tasks paradigm using incongruent stimuli, under the assumption that errors on such trials are partly due to task confusions. Consistent with our predictions, N-2 repetition costs following N-2 errors were found to be reduced when responses in Trial N-1 were fast but were present when the N-1 response was slow. Taken together, our results suggest that task execution leads to associative strengthening of the corresponding task-set, irrespective of response accuracy, and that such automatic strengthening can be counteracted by slowly acting control mechanisms.

The aim of the present study was to examine the interplay of morphological configuration switching and language switching. The morphological configuration is present in word-formation whenever a word contains more than one free morpheme. The morphological configuration is variable both within and between languages for example in two-digit number names (is the decade named first as in twenty-one or the unit named first as in seventeen) and in compound words (is the modifier or the head named first). In the present experiments, participants had to switch between morphological configurations and between languages (German, English, and Spanish). Language-switch cost was measured as the performance difference between language-switch trials and language-repetition trials. In Experiments 1 and 2, participants performed language-comprehension tasks on two-digit numbers and a language-production task on compound words in Experiment 3. All three experiments revealed an under-additive switch cost pattern in which a larger language-switch cost occurred in morphological configuration-repetition trials than in morphological configuration-switch trials. Thus, the present data indicate integration of the morphological configuration and language into one language-related schema--irrespective of the language task (comprehension vs. production) and the type of stimuli (number words vs. compound nouns).

Speaking two or more languages shows bilingual flexibility, but flexible switching requires language control and often incurs performance costs. We examined inhibitory control assessing n − 2 repetition costs when switching three languages (L1 [German], L2 [English], L3 [French]). These costs denote worse performance in n − 2 repetitions (e.g., L2–L3–L2) than in n − 2 nonrepetitions (e.g., L1–L3–L2), indicating persisting inhibition. In two experiments (n = 28 in Experiment 1; n = 44 in Experiment 2), n − 2 repetition costs were observed, but only for L2. Looking into L2 trials specifically, we found n − 2 repetition costs when switching back to L2 from the still weaker L3 but not when returning from the stronger L1, suggesting that L2 is a strong competitor for L3 (requiring L2 inhibition) but less so for L1. Finding n − 2 repetition costs supports an inhibitory account of language control in general, but our study shows only partial evidence for the theoretically assumed more specific relation between language dominance and language inhibition (i.e., only for dominance relations with respect to L1 and L3 when switching back to L2). Taken together, the findings thus suggest the need for further refinement of the concept of language dominance and its relation to inhibition. [ABSTRACT FROM AUTHOR]

Responses are slower in two-choice tasks when either a previous stimulus feature or the previous response repeats than when all features repeat or all features change. Current views of action control posit that such partial repetition costs (PRCs) index the time to update a prior "binding" between a stimulus feature and the response or to resolve processing conflicts between retrieved and current features. However, violating a heuristic that stimulus feature repetitions and changes "signal" repetitions or changes of the previous response, respectively, may also contribute to such costs. To determine whether such relational codes affect performance, we compared PRCs in two- and four-choice tasks. While a stimulus feature repetition signals a response repetition in both tasks, a stimulus feature change signals a specific alternative response only in a two-choice task. Consistent with the signaling hypothesis, we observed similar complete repetition benefits in the two- and four-choice tasks but smaller complete change benefits in the four-choice task. We also investigated whether the smaller complete change benefit in the four-choice task—that is, the signaling effect—varies with the validity of the signal in the previous trial. In all four experiments, we observed a larger signaling effect after trials in which stimulus changes or repetitions corresponded to response changes or repetitions, respectively, than after trials in which stimulus changes did not correspond with response changes. We conclude that signaling contributes to PRCs, which indicates that bindings include relational codes. [ABSTRACT FROM AUTHOR]