Journal of Experimental Psychology: General

We provide evidence that the brain searches for salient stimuli below the level of conscious awareness. We show that, while targets are found very efficiently in Rapid Serial Visual Presentation (RSVP), distractors do not leave a strong memory trace, especially if the memory probe is unexpected. This fits with traditional theories of late attentional selection, whereby "correct rejections" of non-targets are performed with very little processing cost. Our findings are also consistent with the tokenized percept theory of conscious perception, one element of which is that conscious awareness is required to provide sustained representations.

The ability to evaluate ones own knowledge states is often studied using paradigms in which participants make a decision and subsequently report their confidence. This structure has motivated hierarchical models in which confidence arises from a metacognitive process, distinct from the decision process itself, that estimates the probability that the choice is correct (Meyniel et al., 2015; Pouget et al., 2016; Fleming and Daw, 2017). Here, we contrast this framework with an alternative based on an intentional architecture (Shadlen et al., 2008). In this account, choice and confidence are determined simultaneously through a multidimensional drift-diffusion process, where each dimension represents one choice-confidence combination (Ratcliff and Starns, 2009, 2013). Choice, response time, and confidence jointly emerge when one of these accumulators reaches a decision bound. To adjudicate between these accounts, we fit both models to behavioral data from two perceptual tasks: a random-dots motion discrimination task with incentivized confidence reports, and a luminance discrimination task without feedback or incentives. The integrated model provided a superior fit for the incentivized motion task, whereas the hierarchical model more accurately captured behavior in the un-incentivized luminance task. These results suggest that confidence does not rely on a single computational mechanism, but rather its implementation may adapt to the specific demands and structure of the task.

Serial dependence - the bias from recent experience on present response - is often linked to shared memory representations. Yet, it remains unclear whether this bias across tasks when stimulus features are shared but response modes differ. To test this, we interleaved temporal reproduction and bisection tasks using a post-cue design that held duration encoding constant while varying motor output across trials. Using structural equation modeling (SEM), we dissociated perceptual (stimulus-driven) and decisional (response-driven) components of serial dependence. With consecutive same tasks, we replicated repulsive perceptual serial dependence and attractive decisional carryover. Critically, these effects vanished across tasks, despite identical stimulus processing - suggesting that consistent motor responses, not shared memory alone, drive sequential biases. Moreover, SEM uncovered repulsive perceptual influences that standard regression missed, highlighting its power to isolate overlapping effects. Together, these findings reveal that response-specific reactivation underpins serial dependence, pointing to motor-context binding as a key factor in temporal decision-making.

Computational models and neurobehavioral data suggest that encoding variability affects forced-choice mnemonic discrimination. Here, we experimentally manipulated encoding variability on the forced-choice Mnemonic Similarity Task by varying stimulus repetitions during encoding. We first generated predictions from a global matching model. Behavioral data supported all predictions. Across most conditions, repetitions consistently enhanced mnemonic discrimination; however, when encoding variability was induced by 3-repetitions of the original version of the non-corresponding lure and 1-repetition of the target during learning, individuals exhibited increased interference. These findings provide further insight into theories of human memory, especially the effect of stimulus repetition on mnemonic discrimination.

In real-life scenarios, individuals frequently engage in tasks that involve searching for one of various items stored in memory. This combined process of visual search and memory search is known as hybrid search. To date, most hybrid search studies have been restricted to average observers looking for previously well-memorized targets in blank backgrounds. Here we investigated the effects of context and the role of memory in hybrid search by modifying the tasks memorization phase to occur in all-new single trials. Additionally, we aimed to assess how individual differences in visual working memory capacity and inhibitory control influence performance during hybrid search. In an online experiment, 110 participants searched for potential targets in images with and without context. A change detection and go/no-go task were also performed to measure working memory capacity and inhibitory control, respectively. We show that, in target present trials, the main hallmarks of hybrid search remain present, with a linear relationship between reaction time and visual set size, and a logarithmic relationship between reaction time and memory set size. Context affected search efficiency in different ways. In target-absent trials we found large differences between context-present and absent conditions, suggesting participants adoption of adaptive strategies. Finally, working memory capacity did not predict most search performance measures. Inhibitory control, when relationships were significant, could account for only a small portion of the variability in the data. This study provides insights into the effects of context and individual differences on search efficiency and termination.

Reinforcement learning (RL) models explain how people adapt behavior through incremental value updates but assume that individual experiences are not explicitly stored or retrieved. Across two experiments (N = 282 and N = 1,818), we tested whether people rely on such explicit memory representations during experience-based choice. Participants sampled outcomes from two lotteries and, in an "ignore" condition, were instructed to disregard specific outcomes before deciding. Ignoring these outcomes substantially altered preferences, suggesting that choices were guided by explicit episodic representations rather than cumulative reinforcement. Frequency judgments revealed generally accurate memory for experienced outcomes, but reduced precision for continuous compared with discrete outcome distributions. These findings challenge purely incremental RL accounts and support theories proposing that human choice integrates flexible episodic memory with reinforcement mechanisms, bridging models of learning, memory, and decision-making. Statement of RelevanceHow people learn from experience shapes decisions in many everyday situations, from choosing a stock to invest in to selecting a restaurant or deciding which route to take home. Our experiments show that people do not rely solely on incremental value updates but instead exploit memory representations of past outcomes to guide choices. When asked to ignore certain outcomes, participants adjusted their preferences in line with these representations. These findings reveal that human decision-making also engages flexible use of memory for past experiences, highlighting the importance of memory-based mechanisms in adaptive, real-world choice behaviour.

Functionally active and passive states in working memory have been related to different neural mechanisms. Memoranda in active states might be maintained by persistent neural firing, whereas memoranda in passive states might be maintained through short-term synaptic plasticity. We reasoned that this might make these items differentially susceptible to interference during maintenance, in particular that passively maintained items might be more robust. To test this hypothesis, we gave our participants a working memory task in which one item was prioritised (active) by always probing it first, while the other item was deprioritised (passive) by always probing it second. In two experiments, on half the trials, we presented an interfering task during memory maintenance, in which the stimuli matched either the feature dimension of the memory items (colour or orientation), or their spatial location. Whether the interfering task appeared on a given trial was unpredictable. In a third experiment where participants were given prior knowledge of the interference condition, and finally in a fourth experiment we used a reward-based prioritisation cue. Across experiments, we found that both active and passive memory items were affected by interference to a similar extent, with overall performance being closely matched in all experiments. We further investigated precision and probability of target response parameters from the standard mixture model, which also showed no differences between states. We conclude that active and passive items, although potentially stored in different neuronal states, do not show differential susceptibility to interference. Public significance statementThe ability to briefly remember information is critical to human cognition. Our so-called working memory is nevertheless rather limited, able to hold only a few items at any one time, and prone to forgetting when we are briefly distracted. Yet, there is reason to believe that not all information in working memory is equally vulnerable. Items that are more passively stored, because they will only be required after some time, might be more resilient to interference. Items that are stored actively, for more immediate recall, might be more easily disrupted. Here, we investigated the effect of an interference task on the retention of both active and passive items in working memory. Our results showed that active and passive items are equally affected by interference, suggesting that resilience in working memory does not depend on the functional state of the items therein.

Efficiently processing self-related information is critical for cognition, yet the earliest mechanisms enabling this self-prioritization remain unclear. By combining a temporal order judgement task with computational modelling based on the Theory of Visual Attention (TVA), we show how mere, arbitrary associations with the self can fundamentally alter attentional selection of sensory information into short-term memory/awareness, by enhancing the attentional weights and processing capacity devoted to encoding socially loaded information. This self-prioritization in attentional selection occurs automatically at early perceptual stages but reduces when active social decoding is required. Importantly, the processing benefits obtained from attentional selection via self-relatedness and via physical salience were additive, suggesting that social and perceptual salience captured attention via separate mechanisms. Furthermore, intra-individual correlations revealed an obligatory self-prioritization effect, whereby self-relatedness overpowered the contribution of perceptual salience in guiding attentional selection. Together, our findings provide evidence for the influence of self-relatedness during earlier, automatic stages of attentional section at the gateway to perception, distinct from later post-attentive processing stages.

Humans are prone to mentally organise the ascending series of integers according to reading habits, so that in western cultures small numbers are positioned to the left of larger ones on a mental number line (MNL, Dehaene et al., 1993). Despite 140 years since seminal observations made by Sir Francis Galton in human observers that experienced vivid MNLs (Galton, 1880a,b), the neural and functional mechanisms that give rise to MNLs remain elusive. Here, in a series of three experiments we show that spatially organised MNLs are not \"all or none\" phenomena and that MNLs get progressively less noisy and more stable in the minds eye, the more an observer fully combines left/right spatial codes with small/large magnitude codes to operate on numbers. These results show that conceptualising the ascending series of integers in spatial terms depends on contextual clues rather than being inherent to the semantic representation of numbers.

An extensive body of literature has shown that humans tend to avoid expending cognitive effort, just like for physical effort or financial resources. How then, do we decide whether to put this effort in? Decision-making not only involves choosing our actions, but also the meta-decision of how much cognitive effort to invest in making this choice, weighing the costs of cognitive effort against potential rewards. Popular recent theories, grounded in the field of reinforcement learning, suggest that this cost-benefit trade-off can be informed by the opportunity costs of effort investment, which the brain may approximate by the estimated average reward rate per unit time. It follows from intuition that in a low reward environment, investing cognitive resources in the task at hand will less likely lead to missed opportunities. Recent studies provided support for this idea, showing that people exert more cognitive effort when reward rate is low. Here, we replicate one of the key previous findings but provide an important nuance to this result. Cognitive effort allocation was better explained by participants recent performance history (i.e. accuracy rate) than average reward rate. In combination with the observation that participants were insensitive to the reward currently at stake, this invites a reinterpretation of these previous findings and suggests the need for further studies to assess whether environmental richness may indeed serve as a heuristic to modulate cognitive effort allocation.

In visual search, improved performance when a target appears at a recently cued location is taken as strong evidence that attention was shifted to this cue. Here, we provide evidence challenging the canonical interpretation of spatial-cueing (or cue-validity) effects and supporting the Priority Accumulation Framework (PAF). According to PAF, attentional priority accumulates over time at each location until the search context triggers selection of the highest-priority location. Spatial-cueing effects reflect how long it takes to resolve the competition and can thus be observed even when attention was never shifted to the cue. Here, we used a spatial-cueing paradigm with abruptly onset cues and search displays varying in target-distractor similarity. We show search performance on valid-cue trials deteriorated the more difficult the search, a finding that is incompatible with the standard interpretation of spatial-cueing effects. By using brief displays (Experiment 1) and by examining the effect of search difficulty on the fastest trials (Experiment 2), we invalidate alternative accounts invoking post-perceptual verification processes (Experiment 1) or occasional failures of the onset cue to capture attention (Experiment 2). In Experiment 3, we used a combination of the spatial-cueing and dot-probe paradigms. We show that the events that occurred in both the cue and search displays affected attentional distribution, and that the relative attentional priority weight that accumulated at the target location determined how easily the competition was resolved. These findings fully support PAFs predictions. Public significance statementMany studies aim at establishing whether certain objects mandatorily capture our attention. Here, we show that there is no "yes-or-no" answer to this question because the context in which an object appears determines whether this object captures attention. We show that our attention is not shifted to the highest-priority object at any given time: instead, information about priority is collected across time until some signal indicates that the appropriate moment for deploying our attention has arrived. Striking failures to notice conspicuous events routinely illustrate how limited our attentional system is: we can attend to very few objects at any given time, and probably to just one. In natural conditions, when we move the focus of our attention from one object to another, we also shift our gaze towards the attended location: this allows us to place the object of most interest in the center of our fovea, which maximizes the quality of its perceptual processing. Tracking the locus of such overt attention is easily achieved by using eye-tracking devices. However, in order to isolate the benefits of attention from the benefits of visual acuity, one must study covert attention - that is, attentional shifts in the absence of eye movements. These shifts are not directly observable and must therefore be inferred using indirect measures of processing.

Previous work has shown that humans distribute their visual working memory (VWM) resources flexibly across items: the higher the importance of an item, the better it is remembered. A related, but much less studied question is whether people also have control over the total amount of VWM resource allocated to a task. Here, we approach this question by testing whether increasing monetary incentives results in better overall VWM performance. In three experiments, subjects performed a delayed-estimation task on the Amazon Turk platform. In the first two experiments, four groups of subjects received a bonus payment based on their performance, with the maximum bonus ranging from $0 to $10 between groups. We found no effect of the amount of bonus on intrinsic motivation or on VWM performance in either experiment. In the third experiment, reward was manipulated on a trial-by-trial basis using a within-subjects design. Again, no evidence was found that VWM performance depended on the magnitude of potential reward. These results suggest that encoding quality in visual working memory is insensitive to monetary reward, which has implications for resource-rational theories of VWM.

Predictive processing is quickly gaining ground as a theory of perception and attention. From this perspective the brain is cast as an organisms predictive model of how its world works and will continue to work in the future. However, research on the brains predictive capacities remains beholden to traditional research practices in which participants are passively shown stimuli without their active involvement. The current study is an investigation into ways in which self-generated predictions may differ from externally induced predictions. Participants completed a volatile spatial attention task under both conditions on different days. We used the Hierarchical Gaussian Filter, an approximate Bayesian inference model, to determine subject-specific parameters of belief-updating and inferred volatility. We found preliminary evidence in support of self-generated predictions incurring a larger reaction time cost when violated compared to predictions induced by sensory cue, which translated to participants increased sensitivity to changes in environmental volatility. Our results suggest that internally generated predictions may be afforded more weight, but these results are complicated by session order and duration effects, as well as a lack of statistical power. We discuss the limitations of our study preventing us from replicating previous research, and ways to remedy these shortcomings in future studies.

Timing studies on statistical learning predominantly present temporal regularities in a discrete, trial-by-trial manner. This, however, is a simplified representation of natures complex temporal structure in which regularities are embedded in a continuous stream of interrupting, irregular events. Recent studies using more complex, dynamic experimental tasks have nevertheless replicate the ubiquitous finding of a performance benefit for regular versus irregular timed events. This regularity benefit is commonly interpreted to emerge from a mechanism that detects and subsequently exploits the regularity as it would be impossible for irregular timed events. In contrast, here we show that this interpretation overlooks the influence of learning various time-related factors that contribute to the regularity benefit in such complex temporal environments. Instead of only learning the temporal regularity, participants exploited the temporal properties of targets that we initially considered as irregular and uninformative. Participants temporally prepared, in parallel, for different actions to perform and locations to attend, irrespective of targets regularity. In fact, this temporal preparation explained regularity benefits without assuming statistical learning of the regular target. Using a computational model, f MTP, we illustrate that such adaptation can arise from associative memory processes underlying temporal preparation.

Working memory serves as a key gateway to the formation of lasting memories. While it is established how attentional focusing during working memory prioritizes internal representations for imminent tasks, the dynamic processes by which such internal focusing affects subsequent long-term memory remain underexplored. We developed a two-stage visual working-memory/long-term-memory task in which we cued visual objects during working memory and tracked the dynamics of attentional deployment through a recently uncovered gaze marker of internal focusing. Across two experiments, we found that attentional focusing during working memory benefits subsequent long-term memory for internally attended objects without a cost to unattended objects. Gaze biases associated with internal focusing revealed how this benefit was supported by the speed of attentional deployment, with faster attentional deployment predicting better subsequent memory. These results highlight how attentional focusing in working memory benefits long-term memory, and uncover the dynamic processes that instill such lasting benefits.

Humans tend to slow down after making an error. A longstanding account of this post-error slowing is that people are simply more cautious. However, accuracy typically does not improve following an error leading some researchers to suggest that an initial orienting response may initially impair performance immediately following error. Unfortunately, characterizing the nature of this error-based impairment remains a challenge in standard tasks that use free response times. Using a new experimental approach, we exert tight control over the timing of responses to reveal the time course of stimulus-response processing. Participants are less accurate after an error even when given ample time to make a response. A computational model of response preparation rules out the possibility that errors lead to slower cognitive processing. Instead, we find that the "efficacy" of cognitive processing in producing an intended response is impaired following errors. Participants commit more perseverative slips of action following an error. Rather than a strategic shift along a single speed-accuracy tradeoff function, post-error slowing observed in free response time tasks may be an adaptive response to impaired cognitive processing that reflects a fundamentally altered relationship between the speed and accuracy of responses.

Making a decision and reporting confidence in the accuracy of that decision are thought to be driven by the same mechanism: the accumulation of evidence. Previous research has shown that choices and reaction times are well accounted for by a computational model assuming noisy accumulation of evidence until crossing a decision boundary (e.g., the drift diffusion model). Decision confidence can be derived from the amount of evidence following post-decision evidence accumulation. Currently, the stopping rule for post-decision evidence accumulation is underspecified. In the current work, we quantitatively and qualitatively compare the ability of four prominent models of confidence couched within evidence accumulation to account for this stopping rule. In two experiments, participants were instructed to make fast or accurate decisions, and to give fast or carefully considered confidence judgments. We then compared the different models in their ability to capture the speed-accuracy effects on confidence. Both qualitatively and quantitatively, the data were best accounted for by our newly proposed Flexible Collapsing Boundaries model, in which post-decision accumulation terminates once it reaches one of two opposing slowly collapsing confidence boundaries. Inspection of the parameters of this model revealed that instructing participants to make fast versus accurate decisions influenced the height of the decision boundaries, while instructing participants to make fast versus careful confidence judgments influenced height of the confidence boundaries. Our data show that the stopping rule for confidence judgments can be well described as an accumulation-to-bound process, and that the height of these confidence boundaries are under strategic control.

Spatial memory is invaluable for most mobile organisms, yet nature of the underlying representations that we employ for spatial memory has been fiercely contested. On the one hand, the presence of place cells in the hippocampus and grid cells in the medial entorhinal cortex appear to support the argument spatial representations may follow Euclidean axioms, termed "the cognitive map hypothesis." On the other hand, decades of behavioral research in humans reveals that spatial memory often shows characteristic distortions, leading to the alternative, cognitive graph hypothesis, to account for this aspect of spatial memory. Importantly, the majority of laboratory studies tend to occur within novel environments in which participants often have only limited exposure and no personal relevance. We were interested in studying large-scale memory across multiple time scales: from a virtual environment (e.g., learned over several minutes) to a college campus (e.g., months to a few years) to a hometown environment (e.g., many years). Across several tasks, we found that participants exhibited systematic distortions in their memory for all of these environments. Likewise, we found significant correlations between performance on several spatial memory tasks (both between participants and within-participant analyses of patterns of errors), thus suggesting that these tasks tap into partially overlapping cognitive representations and supporting their construct validity. Altogether, our findings provide clear evidence for cognitive graph hypothesis and support the construct validity of several spatial memory tasks within large-scale, real-world environments that are learned over the course of several months to years. Public Significance StatementSpatial memory is key for our ability to live independent lives (e.g., patients with Alzheimers disease lose independence, partially due to disorientation in familiar environments). Typical laboratory-based measures of spatial memory use novel environments that may differ in complexity vs. real-world environments (e.g., size, layout, number of landmarks, duration of exploration, personal relevance). We leveraged breakthroughs in technology to study spatial memory across several tasks and temporal scales, from a novel environment navigated over the course of several minutes to a university campus (e.g., months to years) to hometowns (e.g., years to decades). We observed consistent evidence for systematic distortions in spatial memory, which supports the hypothesis that spatial memory is supported by a cognitive graph, thus posing an important challenge to the extremely influential Euclidean, "cognitive map" hypothesis that was awarded a Nobel Prize in 2014.

Visual working memory allows for the brief maintenance of information to serve behavioral goals. It has been shown that when the specific action required to serve a future goal is predictable, people can flexibly change a visual memory representation to incorporate an action-based one, demonstrating the goal-oriented nature of visual working memory. Can such flexibility also be observed within the visual domain, between color and space? In this eye-tracking study, participants remembered either a centrally presented color or a spatial position around fixation. Critically, when remembering a color the response wheel was either randomly rotated, or shown at a fixed rotation, on every trial. When fixed, every target color could be associated with a predictable position on the wheel during response. Do people incorporate this added spatial information in their behavior? Participants utilized color-space associations when remembering color: Response initiation happened faster when the color wheel was fixed compared to random, irrespective of whether an action could be planned or not. Next, we showed that gaze was biased towards the position of the spatial memory target during the delay, extending previous work on gaze biases. Importantly, also when remembering a color, gaze was biased towards the anticipated position of that color on the response wheel when it was fixed. Together, our results show a behavioral benefit of added spatial information for color memory, and systematic changes in gaze that reflect flexible utilization of space.

Confidence in a perceptual decision is a subjective estimate of the accuracy of ones choice. As such, confidence is thought to be an important computation for a variety of cognitive and perceptual processes, and it features heavily in theorizing about conscious access to perceptual states. Recent experiments have revealed a "positive evidence bias" (PEB) in the computations underlying confidence reports. A PEB occurs when confidence, unlike objective choice, over-weights the evidence for the chosen option, relative to evidence against the chosen option. Accordingly, in a perceptual task, appropriate stimulus conditions can be arranged that produce selective changes in confidence reports but no changes in accuracy. Although the PEB is generally assumed to reflect the observers perceptual and/or decision processes, post-decisional accounts have not been ruled out. We therefore asked whether the PEB persisted under novel conditions that eliminated two possible post-decisional accounts: 1) post-decision evidence accumulation that contributes to a confidence report solicited after the perceptual choice, and 2) a memory bias that emerges in the delay between the stimulus offset and the confidence report. We found that even when the stimulus remained on the screen until observers responded, and when observers reported their choice and confidence simultaneously, the PEB still emerged. Signal detection-based modeling also showed that the PEB was not associated with changes to metacognitive efficiency, but rather to confidence criteria. We conclude that once-plausible post-decisional accounts of the PEB do not explain the bias, bolstering the idea that it is perceptual or decisional in nature.