The purpose of the present study was to examine the influence of task set on the spatial and temporal characteristics of eye movements during scene perception. In previous work, when strong control was exerted over the viewing task via specification of a target object (as in visual search), task set biased spatial, rather than temporal, parameters of eye movements. Here, we find that more participant-directed tasks (in which the task establishes general goals of viewing rather than specific objects to fixate) affect not only spatial (e.g., saccade amplitude) but also temporal parameters (e.g. fixation duration). Further, task set influenced the rate of change in fixation duration over the course of viewing but not saccade amplitude, suggesting independent mechanisms for control of these parameters.

The purpose of the present study was to examine the influence of task set on the spatial and temporal characteristics of eye movements during scene perception. In previous work, when strong control was exerted over the viewing task via specification of a target object (as in visual search), task set biased spatial, rather than temporal, parameters of eye movements. Here, we find that more participant-directed tasks (in which the task establishes general goals of viewing rather than specific objects to fixate) affect not only spatial (e.g., saccade amplitude) but also temporal parameters (e.g., fixation duration). Further, task set influenced the rate of change in fixation duration over the course of viewing but not saccade amplitude, suggesting independent mechanisms for control of these parameters.

Variation in political ideology has been linked to differences in attention to and processing of emotional stimuli, with stronger responses to negative versus positive stimuli (negativity bias) the more politically conservative one is. As memory is enhanced by attention, such findings predict that memory for negative versus positive stimuli should similarly be enhanced the more conservative one is. The present study tests this prediction by having participants study 120 positive, negative, and neutral scenes in preparation for a subsequent memory test. On the memory test, the same 120 scenes were presented along with 120 new scenes and participants were to respond whether a scene was old or new. Results on the memory test showed that negative scenes were more likely to be remembered than positive scenes, though, this was true only for political conservatives. That is, a larger negativity bias was found the more conservative one was. The effect was sizeable, explaining 45% of the variance across subjects in the effect of emotion. These findings demonstrate that the relationship between political ideology and asymmetries in emotion processing extend to memory and, furthermore, suggest that exploring the extent to which subject variation in interactions among emotion, attention, and memory is predicted by conservatism may provide new insights into theories of political ideology.

No abstract

In stimulus identification tasks, stimulus and response, and location and response information, is thought to become integrated into a common event representation following a response. Evidence for this feature integration comes from paradigms requiring keypress responses to pairs of sequentially presented stimuli. In such paradigms, there is a robust cost when a target event only partially matches the preceding event representation. This is known as the partial repetition cost. Notably, however, these experiments rely on discrimination responses. Recent evidence has suggested that changing the responses to localization or detection responses eliminates partial repetition costs. If changing the response type can eliminate partial repetition costs it becomes necessary to question whether partial repetition costs reflect feature integration or some other mechanism. In the current study, we look to answer this question by using a design that as closely as possible matched typical partial repetition cost experiments in overall stimulus processing and response requirements. Unlike typical experiments where participants make a cued response to a first stimulus before making a discrimination response to a second stimulus, here we reversed that sequence such that participants made a discrimination response to the first stimulus before making a cued response to the second. In Experiment 1, this small change eliminated or substantially reduced the typically large partial repetition costs. In Experiment 2 we returned to the typical sequence and restored the large partial repetition costs. Experiment 3 confirmed these findings, which have implications for interpreting partial repetition costs and for feature integration theories in general.