Selection history: How reward modulates selectivity of visual attention

The effect of reward and punishment on the extinction of attentional capture elicited by value-related stimuli

Particular features of the stimuli that predict significant outcomes tend to capture our attention in a rather automatic and inflexible way. This form of attention has been described as a Pavlovian bias that mimics the phenomenon of sign-tracking described in animals, where reward-predictive cues become motivational magnets. In humans, Value-Modulated Attentional Capture (VMAC) refers to a phenomenon where distractors that signal high-value outcomes receive higher attentional priority. VMAC is particularly difficult to extinguish, showing a similar persistence often described in animal sign-tracking. In the present study, we evaluated to what extent VMAC would persist using a more specific extinction procedure than previous research, where instead of removing the possibility of obtaining rewards, the different discriminant stimuli that signal reward equate its value. Furthermore, we manipulated between experiments whether the high-value distractor predicted high-reward and high-punishment contingent to response accuracy (mimicking previous research; Experiment 1) or only high-reward (Experiment 2), and also explored the association of VMAC and its persistence with measures of emotional impulsivity employed in past research. Our results show that when both rewards and punishments are possible, VMAC does not extinguish after an extensive extinction stage, nor is it associated with measures of emotional impulsivity. When punishments were removed, we showed that VMAC gradually extinguished both in response times and accuracy and that the persistence of VMAC was significantly associated with positive urgency. We discussed these results on the potential of punishments to qualitatively alter learning and response strategies employed by participants.

Dynamic modulation of spatial selection: Online and anticipatory adjustments in the flanker task

To track the spatiotemporal dynamics of selective attention, we constructed four theory-driven variants of Eriksen's flanker task. In each, subjects made speeded binary categorizations of target arrowhead direction while ignoring surrounding flanker arrowheads, whose direction was either congruent or incongruent to the target. Experiment 1 tracked the temporal evolution of target selection by systematically manipulating onset asynchrony between the target and flankers. In Experiments 2A and 2B, we increased flanker strength (both experiments) and reduced target strength (Experiment 2B only) at various times relative to target onset, exploring the effects of dynamic perceptual inputs on flanker congruency effects. Experiment 3 measured how uncertainty about stimulus location impeded spatial selection. Our findings demonstrate that spatial selection in the flanker task is dynamically modulated by both intra- and supra-trial factors.

Biased attention allocation in major depressive disorder: A replication and exploration of the potential effects of depression history

BACKGROUND

Increased attention allocation to negative-valenced information and decreased attention allocation to positive-valenced information have been implicated in the etiology and maintenance of depression. The Matrix task, a free-viewing eye-tracking attention assessment task, has shown corroborating results, coupled with adequate reliability. Yet, replication efforts are still needed. Therefore, we replicated a previously published study in depression, using the same task and attention measures. We also explored the potential added effect of depression history on attention allocation.

METHODS

Participants diagnosed with major depressive disorder (n = 65) and a matched control group of healthy participants (n = 37) freely viewed 60 different face matrices, each presented for six seconds and comprised of eight sad and eight happy faces. Attention allocation to corresponding areas of interest (AOIs) was compared, and the internal consistency of attention allocation measures was assessed. We then compared the attention allocation of participants amidst their first episode (n = 33) to that of participants with a recurrent depressive episode (n = 32).

RESULTS

A significant group-by-stimulus type (happy vs. sad faces) interaction emerged for total dwell time, replicating the findings of the original study. Groups differed on attention allocation to both the sad and happy faces. No findings emerged for first fixation measures. Internal consistency of the total dwell time measure was high. Depression history had no effect on attention allocation.

LIMITATIONS

Due to ethical constraints (delay of treatment), test-retest reliability was not assessed.

CONCLUSIONS

The Matrix task provides a reliable and replicable measure of attention allocation in MDD, showing no effects for depression history.

The effect of expectancy on conditioned pain modulation: evidence from functional near-infrared spectroscopy

Background and objective

The psychological mechanisms that make Conditioned Pain Modulation (CPM) an effective non-pharmacological intervention are still not fully understood. Expectancy is believed to be a critical psychological factor affecting CPM effects, but its specific role has yet to be fully clarified. This study aims to explore the relationship between expectancy and CPM while providing physiological evidence using functional near-infrared spectroscopy (fNIRS).

Method

A standardized CPM induction paradigm was implemented, with verbal guidance used to induce expectancy. The Numeric Rating Scale (NRS) assessed the intensity of the test stimulus (TS), while an 11-point scale evaluated participants' attentional focus on the TS and the effect of expectancy. fNIRS was employed to monitor changes in prefrontal cortex (PFC) activity.

Results

Expectancy significantly amplified the CPM effect (p = 0.036) while markedly reducing attention to the experimental stimulus (p = 0.004). fNIRS findings indicated significant reductions in activity within the left frontal eye field, left dorsolateral prefrontal cortex, and left frontal pole regions. In the post-test, the control group demonstrated significantly higher cortical activity in the right frontal pole region compared to the expectancy group (p < 0.05). Within the expectancy group, bilateral frontal pole cortical activity was significantly lower in the post-test compared to the pre-test (p < 0.05).

Conclusion

Expectancy represents a key psychological mechanism underlying the CPM effect, potentially modulating its magnitude through attention regulation and accompanied by a reduction in oxygenated hemoglobin activity in the frontal pole region and introduced the Expectancy-Attention-CPM Modulation Model (ECAM).

Statistical learning re-shapes the center-surround inhibition of the visuo-spatial attentional focus

To effectively navigate a crowded and dynamic visual world, our neurocognitive system possesses the remarkable ability to extract and learn its statistical regularities to implicitly guide the allocation of spatial attention resources in the immediate future. The way through which we deploy attention in the visual space has been consistently outlined by a "center-surround inhibition" pattern, wherein a ring of sustained inhibition is projected around the center of the attentional focus to optimize the signal-noise ratio between goal-relevant targets and interfering distractors. While it has been observed that experience-dependent mechanisms could disrupt the inhibitory ring, whether statistical learning of spatial contingencies has an effect on such a surround inhibition and - if any - through which exact mechanisms it unravels are hitherto unexplored questions. Therefore, in a visual search psychophysical experiment, we aimed to fill this gap by entirely mapping the visuo-spatial attentional profile, asking subjects (N = 26) to detect and report the gap orientation of a 'C' letter appearing either as a color singleton (Baseline Condition) or as a non-salient probe (Probe Condition) - among other irrelevant objects - at progressively increasing probe-to-singleton distances. Critically, we manipulated the color singleton spatial contingency so as to make it appear more frequently adjacent to the probe, specifically at a spatial distance where attending the color singleton generates surround-inhibition on the probe, hindering attentional performance. Results showed that statistical learning markedly reshaped the attentional focus, transforming the center-surround inhibition profile into a non-linear gradient one through a performance gain over the high probability probe-to-singleton distance. Noteworthy, such reshaping was uneven in time and asymmetric, as it varied across blocks and specifically appeared only within manipulated visual quadrants, leaving unaltered the unmanipulated ones. Our findings offer insights of theoretical interest in understanding how environmental regularities orchestrate the way we allocate attention in space through plastic re-weighting of spatial priority maps. Additionally, going beyond the physical dimension, our data provide interesting implications about how visual information is coded within working memory representations, especially under scenarios of heightened uncertainty.

Neural mechanisms of learned suppression uncovered by probing the hidden attentional priority map

Attentional capture by an irrelevant salient distractor is attenuated when the distractor appears more frequently in one location, suggesting learned suppression of that location. However, it remains unclear whether suppression is proactive (before attention is directed) or reactive (after attention is allocated). Here, we investigated this using a 'pinging' technique to probe the attentional distribution before search onset. In an EEG experiment, participants searched for a shape singleton while ignoring a color singleton distractor at a high-probability location. To reveal the hidden attentional priority map, participants also performed a continuous recall spatial memory task, with a neutral placeholder display presented before search onset. Behaviorally, search was more efficient when the distractor appeared at the high-probability location. Inverted encoding analysis of EEG data showed tuning profiles that decayed during memory maintenance but were revived by the placeholder display. Notably, tuning was most pronounced at the to-be-suppressed location, suggesting initial spatial selection followed by suppression. These findings suggest that learned distractor suppression is a reactive process, providing new insights into learned spatial distractor suppression mechanisms.

Location- and feature-based selection histories make independent, qualitatively distinct contributions to urgent visuomotor performance

Attention mechanisms guide visuomotor behavior by weighing physical salience and internal goals to prioritize stimuli as choices for action. Although less well studied, selection history, which reflects multiple facets of experience with recent events, is increasingly recognized as a distinct source of attentional bias. To examine how selection history impacts saccadic choices, we trained two macaque monkeys to perform an urgent version of an oddball search task in which a red target appeared among three green distracters, or vice versa. By imposing urgency, performance could be tracked continuously as it transitioned from uninformed guesses to informed choices as a function of processing time. This, in turn, permitted assessment of attentional control as manifest in motor biases, processing speed, and asymptotic accuracy. Here, we found that the probability of making a correct choice was strongly modulated by the histories of preceding target locations and target colors. Crucially, although both effects were gated by success (or reward), their dynamics were clearly distinct: whereas location history promoted a motor bias, color history modulated perceptual sensitivity, and these influences acted independently. Thus, combined selection histories can give rise to enormous swings in visuomotor performance even in simple tasks with highly discriminable stimuli.

Context-dependent modulation of spatial attention: prioritizing behaviourally relevant stimuli

Human attention can be guided by semantic information conveyed by individual objects in the environment. Over time, we learn to allocate attention resources towards stimuli that are behaviourally relevant to ongoing action, leading to attention capture by meaningful peripheral stimuli. A common example includes, while driving, stimuli that imply a possibly hazardous scenario (e.g. a pedestrian about to cross the road) warrant attentional prioritization to ensure safe proceedings. In the current study, we report a novel phenomenon in which the guidance of attention is dependent on the stimuli appearing in a behaviourally relevant context. Using a driving simulator, we simulated a real-world driving task representing an overlearned behaviour for licensed drivers. While driving, participants underwent a peripheral cue-target paradigm where a roadside pedestrian avatar (target) appeared following a cylinder cue. Results revealed that, during simulated driving conditions, participants (all with driver's licenses) showed greater attentional facilitation when pedestrians were oriented towards the road compared to away. This orientation-specific selectivity was not seen if the 3-D context was removed (Experiment 1) or the same visual scene was presented, but participants' viewpoints remained stationary (Experiment 2), or an inanimate object served as a target during simulated driving (Experiment 3). This context-specific attention modulation likely reflects drivers' expertise in automatically attending to behaviourally relevant information in a context-dependent manner.

Contributions of distinct attention mechanisms to saccadic choices in a gamified, dynamic environment

Visuospatial attention is key for parsing visual information and selecting targets to look at. In turn, three types of mechanism determine when and where attention is deployed: stimulus-driven (exogenous), goal-driven (endogenous), and history-driven (reflecting recent experience). It is unclear, however, how these distinct attentional signals interact and contribute during natural visual scanning, when stimuli may change rapidly and no fixation requirements are imposed. Here, we investigate this via a gamified task in which participants make continuous saccadic choices at a rapid pace - and yet, perceptual performance can be accurately tracked over time as the choice process unfolds. The results reveal unequivocal markers of exogenous capture toward salient stimuli; endogenous guidance toward valuable targets and relevant locations; and history-driven effects, which produce large, involuntary modulations in processing capacity. Under dynamic conditions, success probability is dictated by temporally precise interplay between different forms of spatial attention, with recent history making a particularly prominent contribution.

Significance Statement

Visuospatial attention comprises a collection of mental mechanisms that allow us to focus on (or look at) specific objects or parts of space and ignore others. The next target to be inspected is generally selected based on how much it stands out (salience), its relevance to current goals, and recent experience. We designed a gamified visual scanning task in which all such forms of attentional control interact rapidly, more akin to real life situations (e.g., driving through traffic). Each mechanism affected in characteristic ways the probability that participants would look to the correct target at each moment in time. Most notably, we found that the history of recently seen stimuli determines visual processing capacity much more strongly than previously thought.

Time is Confidence: Monetary Incentives Metacognitive Profile on Duration Judgment

The question we addressed in the current study is whether the mere prospect of monetary reward gain affects subjective time perception. To test this question, we collected trial-based confidence reports in a task where participants made categorical decisions about probe durations relative to the reference duration. When there was a potential to gain a monetary reward, the duration was perceived to be longer than in the neutral condition. Confidence, which reflects the perceived probability of being correct, was higher in the reward gain condition than in the neutral condition. We found that confidence influences the sense of time in different participants. Participants with high confidence reported perceiving the duration signaled by the monetary gain condition longer than participants with low confidence. Our results showed that only high confidence individuals overestimated the context of monetary gain. Finally, we found a negative relationship between confidence and time perception, and that confidence bias at the maximum uncertainty duration of 450 ms is predictive of time perception. Taken together, the current study demonstrates that subjective measures of the confidence profile caused an overestimation of time rather than the outcome valence of reward expectancy.

Attentional Capture and Control

The current review presents an integrated tripartite framework for understanding attentional control, emphasizing the interaction and competition among top-down, bottom-up, and selection-history influences. It focuses on attentional capture, which refers to conditions in which salient objects or events receive attentional priority even when they are inconsistent with the goals, tasks, and intentions of the observer. The review describes which components of the tripartite framework are in play when distraction by salient objects is prevented and the conditions in which there is no control over the occurrence of attentional capture. It then concludes that attentional capture can be controlled in a proactive way mainly by implicit statistical learning mechanisms associated with selection history. Current and lingering controversies regarding the control of attentional capture are also discussed.

Visual statistical learning requires attention

Statistical learning is a person's ability to automatically learn environmental regularities through passive exposure. Since the earliest studies of statistical learning in infants, it has been debated exactly how "passive" this learning can be (i.e., whether attention is needed for learning to occur). In Experiment 1 of the current study, participants performed a serial feature search task where they searched for a target shape among heterogenous nontarget shapes. Unbeknownst to the participants, one of these nontarget shapes was presented much more often in location. Even though the regularity concerned a nonsalient, nontarget item that did not receive any attentional priority during search, participants still learned its regularity (responding faster when it was presented at this high-probability location). While this may suggest that not much, if any, attention is needed for learning to occur, follow-up experiments showed that if an attentional strategy (i.e., color subset search or exogenous cueing) effectively prevents attention from being directed to this critical regularity, incidental learning is no longer observed. We conclude that some degree of attention to a regularity is needed for visual statistical learning to occur.

The rise and fall of durable color-induced attentional bias

Target and distractor templates play a pivotal role in guiding attentional control during visual search, with the former template facilitating target search and the latter template leading distractor suppression. We first investigated whether task-irrelevant colors could earn their value through color-target contingency in the training phase and bias attention when they became a distractor in search for a singleton shape during the test phase. Colors provided useful information for target selection, with high- and low-informational values, respectively, in Experiments 1 and 2. Experience-based attentional biases were observed in the first half of the former experiment, and null results were observed in the latter. Experiment 3 verified whether the null results were elicited because the response-relevant feature inside of the singleton shape was also a singleton. Colors were task defined in the training phase, and the test display was the same as that used in Experiment 2. Experience-based attentional biases were observed in the first half of the test phase. In Experiment 4, we tested whether decreasing the consistency of distractor processing can lengthen the duration of experience-based attentional biases by increasing the number of possible response-relevant features inside of the colored distractor. The results showed experience-based attentional biases throughout the test phase. The results highlight the ideas that the informational value provided by a feature dimension for facilitating target selection can modify a target template and that the consistency of rejecting a distractor feature can play a role in the formation of a distractor template.

Interaction of spatial attention and the associated reward value of audiovisual objects

Reward value and selective attention both enhance the representation of sensory stimuli at the earliest stages of processing. It is still debated whether and how reward-driven and attentional mechanisms interact to influence perception. Here we ask whether the interaction between reward value and selective attention depends on the sensory modality through which the reward information is conveyed. Human participants first learned the reward value of uni-modal visual and auditory stimuli during a conditioning phase. Subsequently, they performed a target detection task on bimodal stimuli containing a previously rewarded stimulus in one, both, or neither of the modalities. Additionally, participants were required to focus their attention on one side and only report targets on the attended side. Our results showed a strong modulation of visual and auditory event-related potentials (ERPs) by spatial attention. We found no main effect of reward value but importantly we found an interaction effect as the strength of attentional modulation of the ERPs was significantly affected by the reward value. When reward effects were examined separately with respect to each modality, auditory value-driven modulation of attention was found to dominate the ERP effects whereas visual reward value on its own led to no effect, likely due to its interference with the target processing. These results inspire a two-stage model where first the salience of a high reward stimulus is enhanced on a local priority map specific to each sensory modality, and at a second stage reward value and top-down attentional mechanisms are integrated across sensory modalities to affect perception.

Reward history guides focal attention in whisker somatosensory cortex

Prior reward is a potent cue for attentional capture, but the underlying neurobiology is largely unknown. In a novel whisker touch detection task, we show that mice flexibly shift attention between specific whiskers on a trial-by-trial timescale, guided by the recent history of stimulus-reward association. Two-photon calcium imaging and spike recordings revealed a robust neurobiological correlate of attention in the somatosensory cortex (S1), boosting sensory responses to the attended whisker in L2/3 and L5, but not L4. Attentional boosting in L2/3 pyramidal cells was topographically precise and whisker-specific, and shifted receptive fields toward the attended whisker. L2/3 VIP interneurons were broadly activated by whisker stimuli, motion, and arousal but did not carry a whisker-specific attentional signal, and thus did not mediate spatially focused tactile attention. Together, these findings establish a new model of focal attention in the mouse whisker tactile system, showing that the history of stimuli and rewards in the recent past can dynamically engage local modulation in cortical sensory maps to guide flexible shifts in ongoing behavior.

Reward History and Statistical Learning Independently Impact Attention Search: An ERP Study

Selection history is widely accepted as a vital source in attention control. Reward history indicates that a learned association captures attention even when the reward is no longer presented, while statistical learning indicates that a learned probability exerts its influence on attentional control (facilitation or inhibition). Existing research has shown that the effects of the reward history and statistical learning are additive, suggesting that these two components influence attention priority through different pathways. In the current study, leveraging the temporal resolution advantages of EEG, we explored whether these two components represent independent sources of attentional bias. The results revealed faster responses to the target at the high-probability location compared to low-probability locations. Both the target and distractor at high-probability locations elicited larger early Pd (50-150 ms) and Pd (150-250 ms) components. The reward distractor slowed the target search and elicited a larger N2pc (180-350 ms). Further, no interaction between statistical learning and the reward history was observed in RTs or N2pc. The different types of temporal progression in attention control indicate that statistical learning and the reward history independently modulate the attention priority map.

Dynamics of visual attention in exploration and exploitation for reward-guided adjustment tasks

The learning process encompasses exploration and exploitation phases. While reinforcement learning models have revealed functional and neuroscientific distinctions between these phases, knowledge regarding how they affect visual attention while observing the external environment is limited. This study sought to elucidate the interplay between these learning phases and visual attention allocation using visual adjustment tasks combined with a two-armed bandit problem tailored to detect serial effects only when attention is dispersed across both arms. Per our findings, human participants exhibited a distinct serial effect only during the exploration phase, suggesting enhanced attention to the visual stimulus associated with the non-target arm. Remarkably, although rewards did not motivate attention dispersion in our task, during the exploration phase, individuals engaged in active observation and searched for targets to observe. This behavior highlights a unique information-seeking process in exploration that is distinct from exploitation.

Impact of relative and absolute values on orienting attention in time

Reward has been known to render the reward-associated stimulus more salient to block effective attentional orienting in space. However, whether and how reward influences goal-directed attention in time remains unclear. Here, we used a modified attentional cueing paradigm to explore the effect of reward on temporal attention, in which the valid targets were given a low monetary reward and invalid targets were given a high monetary reward. The results showed that the temporal cue validity effect was significantly smaller when the competitive reward structure was employed (Experiment 1), and we ruled out the possibility that the results were due to the practice effect (Experiment 2a) or a reward-promoting effect (Experiment 2b). When further strengthening the intensity of the reward from 1:10 to 1:100 (Experiment 3), we found a similar pattern of results to those in Experiment 1. These results suggest that reward information which was based on relative instead of absolute values can weaken, but not reverse, the orienting attention in time.

The Impact of Reward Object on Object-Based Attention

Reward has been shown to influence selective attention, yet previous research has primarily focused on rewards associated with specific locations or features, with limited investigation into the impact of a reward object on object-based attention (OBA). Therefore, it remains unclear whether objects previously associated with rewards affect OBA. To address this issue, we conducted two experiments using a paradigm that combined a reward training phase with a modified two-rectangle paradigm. The results indicate that a reward object modulates both space-based attention (SBA) and OBA. When cues appear on a reward object, the effects of both SBA and OBA are amplified compared to when cues appear on a no-reward object. This finding supports the value-driven attentional capture (VDAC) theory, which suggests that a reward object gain enhanced saliency to capture attention, thereby providing a theoretical support for the treatment of conditions such as drug addiction.

Perceptual Observer Modeling Reveals Likely Mechanisms of Face Expression Recognition Deficits in Depression

BACKGROUND

Deficits in face emotion recognition are well documented in depression, but the underlying mechanisms are poorly understood. Psychophysical observer models provide a way to precisely characterize such mechanisms. Using model-based analyses, we tested 2 hypotheses about how depression may reduce sensitivity to detect face emotion: 1) via a change in selectivity for visual information diagnostic of emotion or 2) via a change in signal-to-noise ratio in the system performing emotion detection.

METHODS

Sixty adults, one half meeting criteria for major depressive disorder and the other half healthy control participants, identified sadness and happiness in noisy face stimuli, and their responses were used to estimate templates encoding the visual information used for emotion identification. We analyzed these templates using traditional and model-based analyses; in the latter, the match between templates and stimuli, representing sensory evidence for the information encoded in the template, was compared against behavioral data.

RESULTS

Estimated happiness templates produced sensory evidence that was less strongly correlated with response times in participants with depression than in control participants, suggesting that depression was associated with a reduced signal-to-noise ratio in the detection of happiness. The opposite results were found for the detection of sadness. We found little evidence that depression was accompanied by changes in selectivity (i.e., information used to detect emotion), but depression was associated with a stronger influence of face identity on selectivity.

CONCLUSIONS

Depression is more strongly associated with changes in signal-to-noise ratio during emotion recognition, suggesting that deficits in emotion detection are driven primarily by deprecated signal quality rather than suboptimal sampling of information used to detect emotion.

Cookie cravings - Examining the impact of sugar content information on Christmas treat preferences via mobile eye-tracking

BACKGROUND

Diets high in added sugar can promote the development of overweight. Especially during the Holiday season, when high-sugar food is abundant, people overeat and gain more weight than during other times of the year. The present study with mobile eye-tracking glasses (Pupil Labs Invisible) investigated how sugar content information affects food preference (liking/wanting) and visual attention (where and how long one is looking) in a buffet-like situation.

METHODS

Fifty-eight participants who were well acquainted with the local Christmas traditions and foods (38 female, 19 male, one diverse; mean age = 25 years, SD = 6.3 years; mean body mass index = 22.2 kg/m2, SD = 3.2 kg/m2) were presented with four cookies and two non-food items (wrapped presents) in a free viewing task. Two of the displayed cookies were 'Christmas cookies' (cookies that are traditionally eaten only during the Holiday season) and two cookies had no Christmas association. The cookies were either labeled as cookies made with or without sugar, resulting in a 3 (Category: cookies with sugar, cookies without sugar, non-food) by 2 (Christmas association: yes, no) repeated-measures design.

RESULTS

Analyses of variance indicated that participants reported higher wanting and liking for cookies with sugar, particularly Christmas cookies (interaction effect for wanting: p = .047, ηp2 = .059; interaction effect for liking: p = .017, ηp2 = .084). Sugar-free cookies were fixated more often (p = .028; d = 0.35) and shorter (p < .001; d = 0.64) than sugar cookies.

CONCLUSION

Assuming that cookies are sugar-free reduced the reported preference for this product, which was associated with a more detail-oriented (critical) viewing pattern. The study's findings have potential implications for public health and can aid in developing targeted interventions to promote healthier food choices during festive periods. The new strategies should not focus on the sugar content of foods.

Manipulating the reliability of target-color information modulates value-driven attentional capture

Previously rewarded stimuli slow response times (RTs) during visual search, despite being physically non-salient and no longer task-relevant or rewarding. Such value-driven attentional capture (VDAC) has been measured in a training-test paradigm. In the training phase, the search target is rendered in one of two colors (one predicting high reward and the other low reward). In this study, we modified this traditional training phase to include pre-cues that signaled reliable or unreliable information about the trial-to-trial color of the training phase search target. Reliable pre-cues indicated the upcoming target color with certainty, whereas unreliable pre-cues indicated the target was equally likely to be one of two distinct colors. Thus reliable and unreliable pre-cues provided certain and uncertain information, respectively, about the magnitude of the upcoming reward. We then tested for VDAC in a traditional test phase. We found that unreliably pre-cued distractors slowed RTs and drew more initial eye movements during search for the test-phase target, relative to reliably pre-cued distractors, thus providing novel evidence for an influence of information reliability on attentional capture. That said, our experimental manipulation also eliminated value-dependency (i.e., slowed RTs when a high-reward-predicting distractor was present relative to a low-reward-predicting distractor) for both kinds of distractors. Taken together, these results suggest that target-color uncertainty, rather than reward magnitude, played a critical role in modulating the allocation of value-driven attention in this study.

From learned value to sustained bias: how reward conditioning changes attentional priority

Introduction

Attentional bias to reward-associated stimuli can occur even when it interferes with goal-driven behavior. One theory posits that dopaminergic signaling in the striatum during reward conditioning leads to changes in visual cortical and parietal representations of the stimulus used, and this, in turn, sustains attentional bias even when reward is discontinued. However, only a few studies have examined neural activity during both rewarded and unrewarded task phases.

Methods

In the current study, participants first completed a reward-conditioning phase, during which responses to certain stimuli were associated with monetary reward. These stimuli were then included as non-predictive cues in a spatial cueing task. Participants underwent functional brain imaging during both task phases.

Results

The results show that striatal activity during the learning phase predicted increased visual cortical and parietal activity and decreased ventro-medial prefrontal cortex activity in response to conditioned stimuli during the test. Striatal activity was also associated with anterior cingulate cortex activation when the reward-conditioned stimulus directed attention away from the target.

Discussion

Our findings suggest that striatal activity during reward conditioning predicts the degree to which reward history biases attention through learning-induced changes in visual and parietal activities.

Motivational context and neurocomputation of stop expectation moderate early attention responses supporting proactive inhibitory control

Alterations in attention to cues signaling the need for inhibitory control play a significant role in a wide range of psychopathology. However, the degree to which motivational and attentional factors shape the neurocomputations of proactive inhibitory control remains poorly understood. The present study investigated how variation in monetary incentive valence and stake modulate the neurocomputational signatures of proactive inhibitory control. Adults (N = 46) completed a Stop-Signal Task (SST) with concurrent EEG recording under four conditions associated with stop performance feedback: low and high punishment (following unsuccessful stops) and low and high reward (following successful stops). A Bayesian learning model was used to infer individual's probabilistic expectations of the need to stop on each trial: P(stop). Linear mixed effects models were used to examine whether interactions between motivational valence, stake, and P(stop) parameters predicted P1 and N1 attention-related event-related potentials (ERPs) time-locked to the go-onset stimulus. We found that P1 amplitudes increased at higher levels of P(stop) in punished but not rewarded conditions, although P1 amplitude differences between punished and rewarded blocks were maximal on trials when the need to inhibit was least expected. N1 amplitudes were positively related to P(stop) in the high punishment condition (low N1 amplitude), but negatively related to P(stop) in the high reward condition (high N1 amplitude). Critically, high P(stop)-related N1 amplitude to the go-stimulus predicted behavioral stop success during the high reward block, providing evidence for the role of motivationally relevant context and inhibitory control expectations in modulating the proactive allocation of attentional resources that affect inhibitory control. These findings provide novel insights into the neurocomputational mechanisms underlying proactive inhibitory control under valence-dependent motivational contexts, setting the stage for developing motivation-based interventions that boost inhibitory control.

Trichotomy revisited: A monolithic theory of attentional control

The control of attention was long held to reflect the influence of two competing mechanisms of assigning priority, one goal-directed and the other stimulus-driven. Learning-dependent influences on the control of attention that could not be attributed to either of those two established mechanisms of control gave rise to the concept of selection history and a corresponding third mechanism of attentional control. The trichotomy framework that ensued has come to dominate theories of attentional control over the past decade, replacing the historical dichotomy. In this theoretical review, I readily affirm that distinctions between the influence of goals, salience, and selection history are substantive and meaningful, and that abandoning the dichotomy between goal-directed and stimulus-driven mechanisms of control was appropriate. I do, however, question whether a theoretical trichotomy is the right answer to the problem posed by selection history. If we reframe the influence of goals and selection history as different flavors of memory-dependent modulations of attentional priority and if we characterize the influence of salience as a consequence of insufficient competition from such memory-dependent sources of priority, it is possible to account for a wide range of attention-related phenomena with only one mechanism of control. The monolithic framework for the control of attention that I propose offers several concrete advantages over a trichotomy framework, which I explore here.

Effects of outcome revaluation on attentional prioritisation of reward-related stimuli

Stimuli associated with rewards can acquire the ability to capture our attention independently of our goals and intentions. Here, we examined whether attentional prioritisation of reward-related cues is sensitive to changes in the value of the reward itself. To this end, we incorporated an instructed outcome devaluation (Experiment 1a), "super-valuation" (Experiment 1b), or value switch (Experiment 2) into a visual search task, using eye-tracking to examine attentional prioritisation of stimuli signalling high- and low-value rewards. In Experiments 1a and 1b, we found that prioritisation of high- and low-value stimuli was insensitive to devaluation of a previously high-value outcome, and super-valuation of a previously low-value outcome, even when participants were provided with further experience of receiving that outcome. In Experiment 2, following a value-switch manipulation, we found that prioritisation of a high-value stimulus could not be overcome with knowledge of the new values of outcomes alone. Only when provided with further experience of receiving the outcomes did patterns of attentional prioritisation of high- and low-value stimuli switch, in line with the updated values of the outcomes they signalled. To reconcile these findings, we suggest that participants were motivated to engage in effortful updating of attentional control settings when there was a relative difference between reward values at test (Experiment 2) but that previous settings were allowed to persist when both outcomes had the same value at test (Experiments 1a and 1b). These findings provide a novel framework to further understand the role of cognitive control in driving reward-modulated attention and behaviour.

Aberrant reward learning, but not negative reinforcement learning, is related to depressive symptoms: an attentional perspective

BACKGROUND

Aberrant reward functioning is implicated in depression. While attention precedes behavior and guides higher-order cognitive processes, reward learning from an attentional perspective - the effects of prior reward-learning on subsequent attention allocation - has been mainly overlooked.

METHODS

The present study explored the effects of reward-based attentional learning in depression using two separate, yet complimentary, studies. In study 1, participants with high (HD) and low (LD) levels of depression symptoms were trained to divert their gaze toward one type of stimuli over another using a novel gaze-contingent music reward paradigm - music played when fixating the desired stimulus type and stopped when gazing the alternate one. Attention allocation was assessed before, during, and following training. In study 2, using negative reinforcement, the same attention allocation pattern was trained while substituting the appetitive music reward for gazing the desired stimulus type with the removal of an aversive sound (i.e. white noise).

RESULTS

In study 1 both groups showed the intended shift in attention allocation during training (online reward learning), while generalization of learning at post-training was only evident among LD participants. Conversely, in study 2 both groups showed post-training generalization. Results were maintained when introducing anxiety as a covariate, and when using a more powerful sensitivity analysis. Finally, HD participants showed higher learning speed than LD participants during initial online learning, but only when using negative, not positive, reinforcement.

CONCLUSIONS

Deficient generalization of learning characterizes the attentional system of HD individuals, but only when using reward-based positive reinforcement, not negative reinforcement.

The effect of reward expectation on working memory of emotional faces under different levels of cognitive load: an ERP study

Using event-related potentials (ERPs), this study examined the impact of reward expectations on working memory of emotional faces under different levels of cognitive load in a task combining the N-back paradigm and the reward expectation paradigm. The experiment involved presenting high- or low-reward cues followed by an N-back task for emotional faces with different loads. The accuracy results showed that under a high task load, both reward and emotion effects were significantly observed. However, these effects disappeared under a low task load. Analysis of the ERP data revealed that the early P2 and VPP components exhibited greater responses to fearful faces than to neutral faces. In the later stages, the P3 and LPP components showed greater reactions to high rewards than to low rewards. Additionally, the P2 component was found to be modulated by task load in relation to rewards, the EPN component demonstrated task load modulation with respect to emotions, and the N170 component showed an interaction effect between rewards and emotions. These findings imply that load regulates the reward effect and the emotional superiority effect in the process of working memory for emotional faces. In the cognitive processing of working memory, motivation and emotion jointly influence processing. Emotional factors have a greater impact in the early stage of processing, while motivation factors have a greater impact in the late stage of processing.

Reliability of individual differences in distractor suppression driven by statistical learning

A series of recent studies has demonstrated that attentional selection is modulated by statistical regularities, even when they concern task-irrelevant stimuli. Irrelevant distractors presented more frequently at one location interfere less with search than distractors presented elsewhere. To account for this finding, it has been proposed that through statistical learning, the frequent distractor location becomes suppressed relative to the other locations. Learned distractor suppression has mainly been studied at the group level, where individual differences are treated as unexplained error variance. Yet these individual differences may provide important mechanistic insights and could be predictive of cognitive and real-life outcomes. In the current study, we ask whether in an additional singleton task, the standard measures of attentional capture and learned suppression are reliable and stable at the level of the individual. In an online study, we assessed both the within- and between-session reliability of individual-level measures of attentional capture and learned suppression. We show that the measures of attentional capture, but not of distractor suppression, are moderately stable within the same session (i.e., split-half reliability). Test-retest reliability over a 2-month period was found to be moderate for attentional capture but weak or absent for suppression. RT-based measures proved to be superior to accuracy measures. While producing very robust findings at the group level, the predictive validity of these RT-based measures is still limited when it comes to individual-level performance. We discuss the implications for future research drawing on inter-individual variation in the attentional biases that result from statistical learning.

Reward-based option competition in human dorsal stream and transition from stochastic exploration to exploitation in continuous space

Primates exploring and exploiting a continuous sensorimotor space rely on dynamic maps in the dorsal stream. Two complementary perspectives exist on how these maps encode rewards. Reinforcement learning models integrate rewards incrementally over time, efficiently resolving the exploration/exploitation dilemma. Working memory buffer models explain rapid plasticity of parietal maps but lack a plausible exploration/exploitation policy. The reinforcement learning model presented here unifies both accounts, enabling rapid, information-compressing map updates and efficient transition from exploration to exploitation. As predicted by our model, activity in human frontoparietal dorsal stream regions, but not in MT+, tracks the number of competing options, as preferred options are selectively maintained on the map, while spatiotemporally distant alternatives are compressed out. When valuable new options are uncovered, posterior β1/α oscillations desynchronize within 0.4 to 0.7 s, consistent with option encoding by competing β1-stabilized subpopulations. Together, outcomes matching locally cached reward representations rapidly update parietal maps, biasing choices toward often-sampled, rewarded options.

Exploring the 'mood congruency' hypothesis of attention allocation - An eye-tracking study

BACKGROUND

The 'mood-congruency' hypothesis of attention allocation postulates that individuals' current emotional states affect their attention allocation, such that mood-congruent stimuli take precedence over non-congruent ones. This hypothesis has been further suggested as an underlying mechanism of biased attention allocation in depression.

METHODS

The present research explored the mood-congruency hypothesis using a novel video-based mood elicitation procedure (MEP) and an established eye-tracking attention allocation assessment task, elaborating prior research in the field. Specifically, in Study 1 (n = 91), a video-based MEP was developed and rigorously validated. In study 2 (n = 60), participants' attention allocation to sad and happy face stimuli, each presented separately alongside neutral faces, was assessed before and after the video-based MEP, with happiness induced in one group (n = 30) while inducing sadness in the other (n = 30).

RESULTS

In Study 1, the MEP yielded the intended modification of participants' current mood states (eliciting either sadness or happiness). Study 2 showed that while the MEP modified mood in the intended direction in both groups, replicating the results of Study 1, corresponding changes in attention allocation did not ensue in either group. A Bayesian analysis of pre-to-post mood elicitation changes in attention allocation supported this null finding. Moreover, results revealed an attention bias to happy faces across both groups and assessment points, suggestive of a trait-like positive bias in attention allocation among non-selected participants.

CONCLUSION

Current results provide no evidence supporting the mood-congruency hypothesis, which suggests that (biased) attention allocation may be better conceptualized as a depressive trait, rather than a mood-congruent state.

Adapting attentional control settings in a shape-changing environment

In rich visual environments, humans have to adjust their attentional control settings in various ways, depending on the task. Especially if the environment changes dynamically, it remains unclear how observers adapt to these changes. In two experiments (online and lab-based versions of the same task), we investigated how observers adapt their target choices while searching for color singletons among shape distractor contexts that changed over trials. The two equally colored targets had shapes that differed from each other and matched a varying number of distractors. Participants were free to select either target. The results show that participants adjusted target choices to the shape ratio of distractors: even though the task could be finished by focusing on color only, participants showed a tendency to choose targets matching with fewer distractors in shape. The time course of this adaptation showed that the regularities in the changing environment were taken into account. A Bayesian modeling approach was used to provide a fine-grained picture of how observers adapted their behavior to the changing shape ratio with three parameters: the strength of adaptation, its delay relative to the objective distractor shape ratio, and a general bias toward specific shapes. Overall, our findings highlight that systematic changes in shape, even when it is not a target-defining feature, influence how searchers adjust their attentional control settings. Furthermore, our comparison between lab-based and online assessments with this paradigm suggests that shape is a good choice as a feature dimension in adaptive choice online experiments.

Cortical and subcortical substrates of minutes and days-long object value memory in humans

Obtaining valuable objects motivates many of our daily decisions. However, the neural underpinnings of object processing based on human value memory are not yet fully understood. Here, we used whole-brain functional magnetic resonance imaging (fMRI) to examine activations due to value memory as participants passively viewed objects before, minutes after, and 1-70 days following value training. Significant value memory for objects was evident in the behavioral performance, which nevertheless faded over the days following training. Minutes after training, the occipital, ventral temporal, interparietal, and frontal areas showed strong value discrimination. Days after training, activation in the frontal, temporal, and occipital regions decreased, whereas the parietal areas showed sustained activation. In addition, days-long value responses emerged in certain subcortical regions, including the caudate, ventral striatum, and thalamus. Resting-state analysis revealed that these subcortical areas were functionally connected. Furthermore, the activation in the striatal cluster was positively correlated with participants' performance in days-long value memory. These findings shed light on the neural basis of value memory in humans with implications for object habit formation and cross-species comparisons.

High target prevalence may reduce the spread of attention during search tasks

Target prevalence influences many cognitive processes during visual search, including target detection, search efficiency, and item processing. The present research investigated whether target prevalence may also impact the spread of attention during search. Relative to low-prevalence searches, high-prevalence searches typically yield higher fixation counts, particularly during target-absent trials. This may emerge because the attention spread around each fixation may be smaller for high than low prevalence searches. To test this, observers searched for targets within object arrays in Experiments 1 (free-viewing) and 2 (gaze-contingent viewing). In Experiment 3, observers searched for targets in a Rapid Serial Visual Presentation (RSVP) stream at the center of the display while simultaneously processing occasional peripheral objects. Experiment 1 used fixation patterns to estimate attentional spread, and revealed that attention was narrowed during high, relative to low, prevalence searches. This effect was weakened during gaze-contingent search (Experiment 2) but emerged again when eye movements were unnecessary in RSVP search (Experiment 3). These results suggest that, although task demands impact how attention is allocated across displays, attention may also narrow when searching for frequent targets.

Value-modulated attentional capture is augmented by win-related sensory cues

Attentional prioritisation of stimuli in the environment plays an important role in overt choice. Previous research shows that prioritisation is influenced by the magnitude of paired rewards, in that stimuli signalling high-value rewards are more likely to capture attention than stimuli signalling low-value rewards; and this attentional bias has been proposed to play a role in addictive and compulsive behaviours. A separate line of research has shown that win-related sensory cues can bias overt choices. However, the role that these cues play in attentional selection is yet to be investigated. Participants in this study completed a visual search task in which they responded to a target shape in order to earn reward. The colour of a distractor signalled the magnitude of reward and type of feedback on each trial. Participants were slower to respond to the target when the distractor signalled high reward compared to when the distractor signalled low reward, suggesting that the high-reward distractors had increased attentional priority. Critically, the magnitude of this reward-related attentional bias was further increased for a high-reward distractor with post-trial feedback accompanied by win-related sensory cues. Participants also demonstrated an overt choice preference for the distractor that was associated with win-related sensory cues. These findings demonstrate that stimuli paired with win-related sensory cues are prioritised by the attention system over stimuli with equivalent physical salience and learned value. This attentional prioritisation may have downstream implications for overt choices, especially in gambling contexts where win-related sensory cues are common.

Attentional blur and blink: Effects of adaptive attentional scaling on visual awareness

Attentional scaling is a crucial mechanism that enables us to flexibly allocate our attention to larger or smaller regions in the visual field. Although previous studies have demonstrated the critical role of attentional scaling in visual processing, its impact on modulating visual awareness is not yet fully understood. This study investigates the adaptive control of attentional scaling and its influence on visual awareness in an attentional blink paradigm. Participants were required to attend to the first target's location, which was manipulated either session-wise, trial-wise, or such that it could be learned across a block of trials. Discrete, all-or-none, awareness was expected when attention was allocated to a narrow area, while gradual awareness was expected when attention was allocated to a larger area. We used mixture modeling to assess second target awareness across these different attentional scales. The results revealed that participants could adaptively control their attentional scale both across stable sessions, and through (implicit) statistical learning in blocks of successive trials. This produced gradual perceptual awareness when the participants adopted a broad attentional scale, causing an attentional "blur". However, trial-wise cues did not allow for attentional scaling, resulting in more discrete target perception overall, and an attentional "blink". We conclude that the attentional scale is to some extent under adaptive control during the attentional blink/blur, where it can produce qualitatively different modes of perceptual awareness.

Reward Modulates Visual Responses in the Superficial Superior Colliculus of Mice

The processing of sensory input is constantly adapting to behavioral demands and internal states. The drive to obtain reward, e.g., searching for water when thirsty, is a strong behavioral demand and associating the reward with its source, a certain environment or action, is paramount for survival. Here, we show that water reward increases subsequent visual activity in the superficial layers of the superior colliculus (SC), which receive direct input from the retina and belong to the earliest stages of visual processing. We trained mice of either sex to perform a visual decision task and recorded the activity of neurons in the SC using two-photon calcium imaging and high-density electrophysiological recordings. Responses to visual stimuli in around 20% of visually responsive neurons in the superficial SC were affected by reward delivered in the previous trial. Reward mostly increased visual responses independent from modulations due to pupil size changes. The modulation of visual responses by reward could not be explained by movements like licking. It was specific to responses to the following visual stimulus, independent of slow fluctuations in neural activity and independent of how often the stimulus was previously rewarded. Electrophysiological recordings confirmed these results and revealed that reward affected the early phase of the visual response around 80 ms after stimulus onset. Modulation of visual responses by reward, but not pupil size, significantly improved the performance of a population decoder to detect visual stimuli, indicating the relevance of reward modulation for the visual performance of the animal.SIGNIFICANCE STATEMENT To learn which actions lead to food, water, or safety, it is necessary to integrate the receiving of reward with sensory stimuli related to the reward. Cortical stages of sensory processing have been shown to represent stimulus-reward associations. Here, we show, however, that reward influences neurons at a much earlier stage of sensory processing, the superior colliculus (SC), receiving direct input from the retina. Visual responses were increased shortly after the animal received the water reward, which led to an improved stimulus signal in the population of these visual neurons. Reward modulation of early visual responses may thus improve perception of visual environments predictive of reward.

Statistical learning of target and distractor spatial probability shape a common attentional priority computation

Converging evidence recently put forward the notion that dedicated neurocognitive mechanisms do exist for the suppression of salient, but irrelevant distractors. Along this line, it is plausible to hypothesize that, in appropriate contexts, experience-dependent forms of attentional learning might selectively induce plastic changes within this dedicated circuitry, thus allowing an independent shaping of priorities at the service of attentional filtering. Conversely, previous work suggested that statistical learning (SL) of both target and distractor spatial probability distributions converge in adjusting only the overall attentional priority of locations: in fact, in the presence of an independent manipulation, either related to the target or to the distractor only, SL induces indirect effects (e.g., changes in filtering efficiency due to an uneven distribution of targets), suggesting that SL-induced plastic changes affect a shared neural substrate. Here we tested whether, when (conflicting) target- and distractor-related manipulations are concurrently applied to the very same locations, dedicated mechanisms might support the selective encoding of spatial priority in relation to the specific attentional operation involved. In three related experiments, human healthy participants discriminated the direction of a target arrow, while ignoring a salient distractor, if present; both target and distractor spatial probability distributions were concurrently manipulated in relation to each single location. Critically, the selection bias produced by the target-related SL was marginally reduced by an adverse distractor contingency, and the suppression bias generated by the distractor-related SL was erased, or even reversed, by an adverse target contingency. Our results suggest that even conflicting target- and distractor-related SL manipulations result in the adjustment of a unique spatial priority computation, likely because the process directly relies on direct plastic alterations of shared spatial priority map(s).

The Electrophysiological Markers of Statistically Learned Attentional Enhancement: Evidence for a Saliency-based Mechanism

It is well established that attention can be sharpened through the process of statistical learning (e.g., visual search becomes faster when targets appear at high-relative-to-low probability locations). Although this process of statistically learned attentional enhancement differs behaviorally from the well-studied top-down and bottom-up forms of attention, relatively little work has been done to characterize the electrophysiological correlates of statistically learned attentional enhancement. It thus remains unclear whether statistically learned enhancement recruits any of the same cognitive mechanisms as top-down or bottom-up attention. In the current study, EEG data were collected while participants searched for an ambiguous unique shape in a visual array (the additional singleton task). Unbeknownst to the participants, targets appeared more frequently in one location in space (probability cuing). Encephalographic data were then analyzed in two phases: an anticipatory phase and a reactive phase. In the anticipatory phase preceding search stimuli onset, alpha lateralization as well as the Anterior Directing Attention Negativity and Late Directing Attention Positivity components-signs of preparatory attention known to characterize top-down enhancement-were tested. In the reactive phase, the N2pc component-a well-studied marker of target processing-was examined following stimuli onset. Our results showed that statistically learned attentional enhancement is not characterized by any of the well-known anticipatory markers of top-down attention; yet targets at high probability locations did reliably evoke larger N2pc amplitudes, a finding that is associated with bottom-up attention and saliency. Overall, our findings are consistent with the notion that statistically learned attentional enhancement increases the perceptual salience of items appearing at high-probability locations relative to low-probability locations.

Social norms shape visual appearance: Taking a closer look at the link between social norm learning and perceptual decision-making

One of the most fundamental questions in social psychology is whether norms can change individuals' minds by shaping the visual appearance of stimuli. This question was first raised by Muzafer Sherif (1935). Drawing on the extended social reinforcement account (Germar and Mojzisch, 2019), we aimed to provide a rigorous test of the hypothesis that norm learning leads to a persistent perceptual bias and, hence, to a change in the visual appearance of stimuli. From a methodological perspective, we used both a diffusion model approach and the method of adjustment, a well-established technique from psychophysics and vision research. The results of Experiments 1-3 show that norm effects on perceptual decision-making are robustly replicable, and are due to genuine social influence, that is, they cannot be explained by non-social priming, contingency learning effects (Experiments 1 and 2) or anchoring effects (Experiment 3). Most importantly, by using a psychophysical approach, Experiment 4 shows, for the first time, that social norm learning alters individuals' point of subjective equality and, hence, the visual appearance of stimuli.

Learning to suppress a location is configuration-dependent

Where and what we attend is very much determined by what we have encountered in the past. Recent studies have shown that people learn to extract statistical regularities in the environment resulting in attentional suppression of locations that were likely to contain a distractor, effectively reducing the amount of attentional capture. Here, we asked whether this suppression effect due to statistical learning is dependent on the specific configuration within which it was learned. The current study employed the additional singleton paradigm using search arrays that had a configuration consisting of set sizes of either four or 10 items. Each configuration contained its own high probability distractor location. If learning would generalize across set size configurations, both high probability locations would be suppressed equally, regardless of set size. However, if learning to suppress is dependent on the configuration within which it was learned, one would expect only suppression of the high probability location that matched the configuration within which it was learned. The results show the latter, suggesting that implicitly learned suppression is configuration-dependent. Thus, we conclude that the high probability location is learned within the configuration context within which it is presented.

Learned cognitive control counteracts value-driven attentional capture

Stimuli formerly associated with monetary reward capture our attention, even if this attraction is contrary to current goals (so-called value-driven attentional capture [VDAC], see Anderson (Ann N Y Acad Sci 1369:24-39, 2016), for a review). Despite the growing literature to this topic, little is known about the boundary conditions for the occurrence of VDAC. In three experiments, we investigated the role of response conflicts and spatial uncertainty regarding the target location during the training and test phase for the emergence of value-driven effects. Thus, we varied the occurrence of a response conflict, search components, and the type of task in both phases. In the training, value-driven effects were rather observed if the location of the value-associated target was not predictable and a response conflict was present. Value-driven effects also only occurred, if participants have not learned to deal with a response conflict, yet. However, the introduction of a response conflict during learning of the color-value association seemed to prevent attention to be distracted by this feature in a subsequent test. The study provides new insights not only into the boundary conditions of the learning of value associations, but also into the learning of cognitive control.

Pinging the brain to reveal the hidden attentional priority map using encephalography

Attention has been usefully thought of as organized in priority maps - putative maps of space where attentional priority is weighted across spatial regions in a winner-take-all competition for attentional deployment. Recent work has highlighted the influence of past experiences on the weighting of spatial priority - called selection history. Aside from being distinct from more well-studied, top-down forms of attentional enhancement, little is known about the neural substrates of history-mediated attentional priority. Using a task known to induce statistical learning of target distributions, in an EEG study we demonstrate that this otherwise invisible, latent attentional priority map can be visualized during the intertrial period using a 'pinging' technique in conjunction with multivariate pattern analyses. Our findings not only offer a method of visualizing the history-mediated attentional priority map, but also shed light on the underlying mechanisms allowing our past experiences to influence future behavior.

Integrated effects of top-down attention and statistical learning during visual search: An EEG study

The present study aims to investigate how the competition between visual elements is solved by top-down and/or statistical learning (SL) attentional control (AC) mechanisms when active together. We hypothesized that the "winner" element that will undergo further processing is selected either by one AC mechanism that prevails over the other, or by the joint activity of both mechanisms. To test these hypotheses, we conducted a visual search experiment that combined an endogenous cueing protocol (valid vs. neutral cue) and an imbalance of target frequency distribution across locations (high- vs. low-frequency location). The unique and combined effects of top-down control and SL mechanisms were measured on behaviour and amplitudes of three evoked-response potential (ERP) components (i.e., N2pc, P1, CNV) related to attentional processing. Our behavioural results showed better performance for validly cued targets and for targets in the high-frequency location. The two factors were found to interact, so that SL effects emerged only in the absence of top-down guidance. Whereas the CNV and P1 only displayed a main effect of cueing, for the N2pc we observed an interaction between cueing and SL, revealing a cueing effect for targets in the low-frequency condition, but not in the high-frequency condition. Thus, our data support the view that top-down control and SL work in a conjoint, integrated manner during target selection. In particular, SL mechanisms are reduced or even absent when a fully reliable top-down guidance of attention is at play.

Neural bases of reward anticipation in healthy individuals with low, mid, and high levels of schizotypy

A growing body of research has placed the ventral striatum at the center of a network of cerebral regions involved in anticipating rewards in healthy controls. However, little is known about the functional connectivity of the ventral striatum associated with reward anticipation in healthy controls. In addition, few studies have investigated reward anticipation in healthy humans with different levels of schizotypy. Here, we investigated reward anticipation in eighty-four healthy individuals (44 females) recruited based on their schizotypy scores. Participants performed a variant of the Monetary Incentive Delay Task while undergoing event-related fMRI.Participants showed the expected decrease in response times for highly rewarded trials compared to non-rewarded trials. Whole-brain activation analyses replicated previous results, including activity in the ventral and dorsal striatum. Whole-brain psycho-physiological interaction analyses of the left and right ventral striatum revealed increased connectivity during reward anticipation with widespread regions in frontal, parietal and occipital cortex as well as the cerebellum and midbrain. Finally, we found no association between schizotypal personality severity and neural activity and cortico-striatal functional connectivity. In line with the motivational, attentional, and motor functions of rewards, our data reveal multifaceted cortico-striatal networks taking part in reward anticipation in healthy individuals. The ventral striatum is connected to regions of the salience, attentional, motor and visual networks during reward anticipation and thereby in a position to orchestrate optimal goal-directed behavior.

Reward History Modulates the Processing of Task-Irrelevant Emotional Faces in a Demanding Task

The aim of the current study was to examine how reward-associated emotional facial distractors could capture attentional resources in a demanding visual task using event-related potentials (ERPs). In the learning phase, a high- or low-reward probability was paired with angry, happy, or neutral faces. Then, in the test phase, participants performed a face-irrelevant task with no reward at stake, in which they needed to discriminate the length of two lines presented in the center of the screen while faces that were taken from the learning phase were used as distractors presented in the periphery. The behavioral results revealed no effect of distractor emotional valence since the emotional information was task-irrelevant. The ERP results in the test phase revealed a significant main effect of distractor emotional valence for the parieto-occipital P200 (170-230 ms); the mean amplitudes in both the angry- and happy-face conditions were more positive than the neutral-face condition. Moreover, we found that the high-reward association enhanced both the N170 (140-180 ms) and EPN (260-330 ms) relative to the low-reward association condition. Finally, the N2pc (270-320 ms) also exhibited enhanced neural activity in the high-reward condition compared to the low-reward condition. The absence of emotional effects indicated that task-irrelevant emotional facial stimuli did not impact behavioral or neural responses in this highly demanding task. However, reward-associated information was processed when attention was directed elsewhere, suggesting that the processing of reward-associated information worked more in an automatic way, irrespective of the top-down task demand.

Rewards weaken cross-modal inhibition of return with visual targets

Previous studies have shown that rewards weaken visual inhibition of return (IOR). However, the specific mechanisms underlying the influence of rewards on cross-modal IOR remain unclear. Based on the Posner exogenous cue-target paradigm, the present study was conducted to investigate the effect of rewards on exogenous spatial cross-modal IOR in both visual cue with auditory target (VA) and auditory cue with visual target (AV) conditions. The results showed the following: in the AV condition, the IOR effect size in the high-reward condition was significantly lower than that in the low-reward condition. However, in the VA condition, there was no significant IOR in either the high- or low-reward condition and there was no significant difference between the two conditions. In other words, the use of rewards modulated exogenous spatial cross-modal IOR with visual targets; specifically, high rewards may have weakened IOR in the AV condition. Taken together, our study extended the effect of rewards on IOR to cross-modal attention conditions and demonstrated for the first time that higher motivation among individuals under high-reward conditions weakened the cross-modal IOR with visual targets. Moreover, the present study provided evidence for future research on the relationship between reward and attention.

Norepinephrine system at the interface of attention and reward

Reward learning is key to survival for individuals. Attention plays an important role in the rapid recognition of reward cues and establishment of reward memories. Reward history reciprocally guides attention to reward stimuli. However, the neurological processes of the interplay between reward and attention remain largely elusive, due to the diversity of the neural substrates that participate in these two processes. In this review, we delineate the complex and differentiated locus coeruleus norepinephrine (LC-NE) system in relation to different behavioral and cognitive substrates of reward and attention. The LC receives reward related sensory, perceptual, and visceral inputs, releases NE, glutamate, dopamine and various neuropeptides, forms reward memories, drives attentional bias and selects behavioral strategies for reward. Preclinical and clinical studies have found that abnormalities in the LC-NE system are involved in a variety of psychiatric conditions marked by disturbed functions in reward and attention. Therefore, we propose that the LC-NE system is an important hub in the interplay between reward and attention as well as a critical therapeutic target for psychiatric disorders characterized by compromised functions in reward and attention.

Inversion of pop-out for a distracting feature dimension in monkey visual cortex

During visual search, it is important to reduce the interference of distracting objects in the scene. The neuronal responses elicited by the search target stimulus are typically enhanced. However, it is equally important to suppress the representations of distracting stimuli, especially if they are salient and capture attention. We trained monkeys to make an eye movement to a unique "pop-out" shape stimulus among an array of distracting stimuli. One of these distractors had a salient color that varied across trials and differed from the color of the other stimuli, causing it to also pop-out. The monkeys were able to select the pop-out shape target with high accuracy and actively avoided the pop-out color distractor. This behavioral pattern was reflected in the activity of neurons in area V4. Responses to the shape targets were enhanced, while the activity evoked by the pop-out color distractor was only briefly enhanced, directly followed by a sustained period of pronounced suppression. These behavioral and neuronal results demonstrate a cortical selection mechanism that rapidly inverts a pop-out signal to "pop-in" for an entire feature dimension thereby facilitating goal-directed visual search in the presence of salient distractors.

Visual-cortical enhancement by acoustic distractors: The effects of endogenous spatial attention and visual working memory load

Past work has shown that when a peripheral sound captures our attention, it activates the contralateral visual cortex as revealed by an event-related potential component labelled the auditory-evoked contralateral occipital positivity (ACOP). This cross-modal activation of the visual cortex has been observed even when the sounds were not relevant to the ongoing task (visual or auditory), suggesting that peripheral sounds automatically activate the visual cortex. However, it is unclear whether top-down factors such as visual working memory (VWM) load and endogenous attention, which modulate the impact of task-irrelevant information, may modulate this spatially-specific component. Here, we asked participants to perform a lateralized VWM task (change detection), whose performance is supported by both endogenous spatial attention and VWM storage. A peripheral sound that was unrelated to the ongoing task was delivered during the retention interval. The amplitude of sound-elicited ACOP was analyzed as a function of the spatial correspondence with the cued hemifield, and of the memory array set-size. The typical ACOP modulation was observed over parieto-occipital sites in the 280-500 ms time window after sound onset. Its amplitude was not affected by VWM load but was modulated when the location of the sound did not correspond to the hemifield (right or left) that was cued for the change detection task. Our results suggest that sound-elicited activation of visual cortices, as reflected in the ACOP modulation, is unaffected by visual working memory load. However, endogenous spatial attention affects the ACOP, challenging the hypothesis that it reflects an automatic process.