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Prospective memory (PM) refers to remembering to perform intended actions in the future. Older adults in particular have been shown to be negatively affected by PM tasks that require a high amount of attentional resources (i.e., nonfocal tasks). This age-related PM deficit has been attributed to reduced target monitoring in this age group older adults. However, this conclusion was based on indirect measures of monitoring, such as costs of the ongoing task. The present study set out to 1) investigate older adults' PM target monitoring by, for the first time, employing a direct measure (i.e., eye tracking), 2) assess differences in monitoring between PM tasks that differ in their focality, and 3) examine whether differences in PM monitoring can indeed explain older adults' reduced PM performance in nonfocal tasks. Results demonstrate that while older, but not younger adults, showed reduced performance in a nonfocal PM task, overt monitoring (eye movements) of these groups did not differ between focality conditions. Further analyses showed that older adults' performance was still reduced on the strategically more demanding task after controlling for overt target monitoring (i.e., including only trials in which the participant monitored). In contrast to indirect measures of cue monitoring, our findings illustrate that older adults' deficits on nonfocal PM tasks cannot (exclusively) be explained by reduced monitoring. Instead, processing that takes place after target monitoring are discussed as possible mechanisms underlying older adults' reduced PM performance in nonfocal tasks.

When two verniers are presented in rapid succession at the same location, feature fusion occurs. Instead of perceiving two separate verniers, participants typically report perceiving one fused vernier, whose offset is a combination of the two previous verniers, with the later one slightly dominating. Here, we examined the effects of sustained attention-the voluntary component of spatial attention-on feature fusion. One way to manipulate sustained attention is via the degree of certainty regarding the stimulus location. In the attended condition, the stimulus appeared always in the same location, and in the unattended condition it could appear in one of two possible locations. Participants had to report the offset of the fused vernier. Experiments 1 and 2 measured attentional effects on feature fusion with and without eye-tracking. In both experiments, we found a higher rate of reports corresponding to the offset of the second vernier with focused attention than without focused attention, suggesting that attention strengthened the final percept emerging from the fusion operation. In Experiment 3, we manipulated the stimulus duration to encourage a final fused percept that is dominated by either the first or second vernier. We found that attention strengthened the already dominant percept, regardless of whether it corresponded to the offset of the first or second vernier. These results are consistent with an attentional mechanism of signal enhancement at the encoding stage.

The motion of parts of an object is usually perceived relative to the object, i.e., nonretinotopically, rather than in retinal coordinates. For example, we perceive a reflector to rotate on the wheel of a moving bicycle even though its trajectory is cycloidal on the retina. The rotation is perceived because the motion of the object (bicycle) is discounted from the motion of its parts (reflector). It seems that the visual system can easily compute the object motion and subtract it from the part motion. Bikes move usually rather predictably. Given the complexity of real-world motion computations, including many ill-posed problems such as the motion correspondence problem, predictability of an object's motion may be essential for nonretinotopic perception. Here, we used the Ternus-Pikler display to investigate this question. Performance was not impaired when contrast polarity, shape, and motion trajectories changed unpredictably. Our findings suggest that predictability is not crucial for nonretinotopic motion processing.

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