There is an ongoing debate about whether fixation durations during reading are only influenced by the processing difficulty of the words being fixated (i.e., the serial-attention hypothesis) or whether they are also influenced by the processing difficulty of the previous and/or upcoming words (i.e., the attention-gradient hypothesis). This article…

We validate an eye-tracking method applicable for studying memory processes in complex cognitive tasks. The method is tested with a task on probabilistic inferences from memory. It provides valuable data on the time course of processing, thus clarifying previous results on heuristic probabilistic inference. Participants learned cue values of…

We investigated whether focal/nonfocal effects (e.g., Einstein et al., 2005) in prospective memory (PM) are explained by cue differences in monitoring difficulty. In Experiment 1, we show that syllable cues (used in Einstein et al., 2005) are more difficult to monitor for than are word cues; however, initial-letter cues (in words) are similar in…

The main challenge for theories of multitasking is to predict when and how tasks interfere. Here, we focus on interference related to the problem state, a directly accessible intermediate representation of the current state of a task. On the basis of Salvucci and Taatgen's (2008) threaded cognition theory, we predict interference if 2 or more…

Voluntary action can be studied by giving participants free choice over which task to perform in response to each presented stimulus. In such experiments, performance costs are observed when participants choose to switch tasks from the previous trial. It has been proposed that these costs primarily index the time-consuming operation of top-down…