Insight problems are problems where the problem solver struggles to find a solution until * aha! * the solution suddenly appears. Two contemporary theories suggest that insight problems are difficult either because problem solvers begin with an incorrect representation of the problem, or that problem solvers apply inappropriate heuristics to the problem. The relative contributions of representational change and inappropriate heuristics on the process of insight problem solving was studied with a task that required the problem solver to move two matchsticks in order to transform an incorrect arithmetic statement into a correct one. Problem solvers (N = 120) worked on two different types of two-move matchstick arithmetic problems that both varied with respect to the effectiveness of heuristics and to the degree of a necessary representational change of the problem representation. A strong influence of representational change on solution rates was found whereas the influence of heuristics had minimal effects on solution rates. That is, the difficulty of insight problems within the two-move matchstick arithmetic domain is governed by the degree of representational change required. A model is presented that details representational change as the necessary condition for ensuring that appropriate heuristics can be applied on the proper problem representation.

Sudden changes in our environment like sound bursts or light flashes are thought to automatically attract our attention thereby affecting responses to subsequent targets, although an alternative view (the contingent attentional capture account) holds that stimuli only capture our attention when they match target features. In the current study, we examined whether an extended version of the latter view can explain exogenous cuing effects on speed and accuracy of performance to targets (uncued-cued) in multimodal settings, in which auditory and visual stimuli co-occur. To this end, we determined whether observed effects of visual and auditory cues, which were always intermixed, depend on top-down settings in "pure" blocks, in which only one target modality occurred, as compared to "mixed" blocks, in which targets were either visual or auditory. Results revealed that unimodal and crossmodal cuing effects depend on top-down settings. However, our findings were not in accordance with predictions derived from the extended contingent attentional capture account. Specifically, visual cues showed comparable effects for visual targets in pure and mixed blocks, but also a comparable effect for auditory targets in pure blocks, and most surprisingly, an opposite effect in mixed blocks. The latter result suggests that visual stimuli may distract attention from the auditory modality in case when the modality of the forthcoming target is unknown. The results additionally revealed that the Simon effect, the influence of correspondence or not between stimulus and response side, is modulated by exogenous cues in unimodal settings, but not in crossmodal settings. These findings accord with the view that attention plays an important role for the Simon effect, and additionally questions the directness of links between maps of visual and auditory space.

Exogenous and endogenous response priming were investigated by comparing performance on stimulus-response compatibility (SRC) and response-effect compatibility (REC) tasks using a repeated measures design. In the SRC task, participants made finger taps at high or low locations in response to centrally presented visual stimuli paired with high- or low-pitched tones. In the REC task, the tones were triggered by responses instead of being presented with the visual stimuli, and hence effects of REC on response times reflect the anticipation of forthcoming tones. Results indicated that response times were shorter with compatible mappings between tones and responses than with incompatible mappings in both tasks. Although these SRC and REC effects did not differ reliably in magnitude, they were uncorrelated across participants. Thus, although exogenous and endogenous response priming may be functionally equivalent at the level of the group, it is unclear whether this is the case at the level of the individual.