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Emotional memory can persist strikingly long, but it is believed that not all its elements are protected against the fading effects of time. So far, studies of emotional episodic memory have mostly investigated retention up to 24h postencoding and revealed that central emotional features (items) are usually strengthened, while contextual binding of the event is reduced. However, even though it is known for neutral memories that central versus contextual elements evolve differently with longer passage of time, the time-dependent evolution of emotional memories remains unclear. Hypothetically, compared to neutral memories, emotional item memory becomes increasingly stronger, accompanied by accelerated decay of--already fragile--links with their original encoding contexts, resulting in progressive reductions in contextual dependency. Here, we tested these predictions in a large-scale study. Participants encoded emotional and neutral episodes, and were assessed 30 minutes (N = 40), 1 day (N = 40), 1 week (N = 39), or 2 weeks (N = 39) later on item memory, contextual dependency, and subjective quality of memory. The results show that, with the passage of time, emotional memories were indeed characterized by increasingly stronger item memory and weaker contextual dependency. Interestingly, analyses of the subjective quality of memories revealed that stronger memory for emotional items with time was expressed in familiarity, whereas increasingly smaller contextual dependency for emotional episodes was reflected in recollection. Together, these findings uncover the timedependent transformation of emotional episodic memories, thereby shedding light on the ways healthy and maladaptive human memories may develop. [ABSTRACT FROM AUTHOR]

Studies on intertrial priming have shown that in visual search experiments, the preceding trial automatically affects search performance: facilitating it when the target features repeat and giving rise to switch costs when they change--so-called (short-term) intertrial priming. These effects also occur at longer time scales: When 1 of 2 possible target colors is more frequent during an experiment block, this results in a prolonged and persistent facilitation for the color that was biased, long after the frequency bias is gone--so-called long-term priming. In this study, we explore the robustness of such long-term priming. In Experiment 1, participants were fully informed of the bias and instructed to prioritize the other unbiased color. Despite these instructions, long-term priming of the biased color persisted in this block, suggesting that guidance by long-term priming is an implicit effect. In Experiment 2, long-term priming was built up in 1 experimental session and was then assessed in a second session a week later. Long-term priming persisted across this week, emphasizing that long-term priming is truly a phenomenon of long-term memory. The results support the view that priming results from the automatic and implicit retrieval of memory traces of past trials. [ABSTRACT FROM AUTHOR]

The hazard function describes the conditional probability that an event will occur at a given moment, given that it has not yet occurred. In warned reaction time tasks, it is a classical finding that the response to a target stimulus is faster as its hazard is higher, which has led to the widespread belief that hazard somehow drives temporal preparation. Alternatively, recent cognitive theories propose that temporal preparation is driven by memory traces of earlier timing experiences. To distinguish between these views, we presented different groups of participants with different distributions of foreperiods between temporal cues and target stimuli. Three experiments revealed clear transfer effects of this manipulation in a test phase where all participants received, after explicit instruction, the same uniform distribution. These findings demonstrate that temporal preparation is driven by past experience, not by current hazard. [ABSTRACT FROM AUTHOR]

Although many of our perceptual biases stem from long-term, repeated exposure, current theories of visual search assume a central role for visual working memory (VWM) in guiding attention to target information. Crucially, whether a VWM representation guides attention depends on the relative priority that the memory has within VWM. Here, in a combined visual search/VWM task, we used attentional guidance by irrelevant memories to measure how long a target representation remains prioritized in VWM when observers repeatedly search for the same target. Irrelevant memories started guiding attention already when the target was repeated once, indicating that the target representation rapidly lost priority within VWM as it moved to long-term memory. By showing that training can lead to interference from irrelevant memories, the findings resolve a long-standing paradox on why VWM appears central to, yet at the same time not sufficient nor necessary for attentional guidance. [ABSTRACT FROM AUTHOR]

Temporal preparation is the cognitive function that takes place when anticipating future events. This is commonly considered to involve a process that maximizes preparation at time points that yield a high hazard. However, despite their prominence in the literature, hazard-based theories fail to explain the full range of empirical preparation phenomena. Here, we present the formalized multiple trace theory of temporal preparation (f MTP), an integrative model which develops the alternative perspective that temporal preparation results from associative learning. f MTP builds on established computational principles from the domains of interval timing, motor planning, and associative memory. In f MTP, temporal preparation results from associative learning between a representation of time on the one hand and inhibitory and activating motor units on the other hand. Simulations demonstrate that f MTP can explain phenomena across a range of time scales, from sequential effects operating on a time scale of seconds to long-term memory effects occurring over weeks. We contrast f MTP with models that rely on the hazard function and show that f MTP's learning mechanisms are essential to capture the full range of empirical effects. In a critical experiment using a Gaussian distribution of foreperiods, we show the data to be consistent with f MTP's predictions and to deviate from the hazard function. Additionally, we demonstrate how changing f MTP's parameters can account for participant-to-participant variations in preparation. In sum, with f MTP we put forward a unifying computational framework that explains a family of phenomena in temporal preparation that cannot be jointly explained by conventional theoretical frameworks. [ABSTRACT FROM AUTHOR]

Decades of reading research have led to sophisticated accounts of single-word recognition and, in parallel, accounts of eye-movement control in text reading. Although these two endeavors have strongly advanced the field, their relative independence has precluded an integrated account of the reading process. To bridge the gap, we here present a computational model of reading, OBI-reader, which integrates insights from both literatures. Key features of OBI are as follows: (1) parallel processing of multiple words, modulated by an attentional window of adaptable size; (2) coding of input through a layer of open bigram nodes that represent pairs of letters and their relative position; (3) activation of word representations based on constituent bigram activity, competition with other word representations and contextual predictability; (4) mapping of activated words onto a spatiotopic sentence-level representation to keep track of word order; and (5) saccade planning, with the saccade goal being dependent on the length and activation of surrounding word units, and the saccade onset being influenced by word recognition. A comparison of simulation results with experimental data shows that the model provides a fruitful and parsimonious theoretical framework for understanding reading behavior. [ABSTRACT FROM AUTHOR]