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Visual attention may be captured by an irrelevant yet salient distractor, thereby slowing search for a relevant target. This phenomenon has been widely studied using the additional singleton paradigm in which search items are typically all presented at one and the same eccentricity. Yet, differences in eccentricity may well bias the competition between target and distractor. Here we investigate how attentional capture is affected by the relative eccentricities of a target and a distractor. Participants searched for a shape-defined target in a grid of homogeneous nontargets of the same color. On 75% of trials, one of the nontarget items was replaced by a salient color-defined distractor. Crucially, target and distractor eccentricities were independently manipulated across three levels of eccentricity (i.e., near, middle, and far). Replicating previous work, we show that the presence of a distractor slows down search. Interestingly, capture as measured by manual reaction times was not affected by target and distractor eccentricity, whereas capture as measured by the eyes was: items close to fixation were more likely to be selected than items presented further away. Furthermore, the effects of target and distractor eccentricity were largely additive, suggesting that the competition between saliency- and relevance-driven selection was modulated by an independent eccentricity-based spatial component. Implications of the dissociation between manual and oculomotor responses are also discussed.

The major goal of the current study is to test whether the feelings of hate and love influence individuals’ visual attention by using a classical task – attentional blink (AB) task. The attentional blink means that in a rapid serial visual presentation (RSVP), attention is temporarily undermined for new input when earlier relevant visual information is being processed. The potential effect of hate and love could be twofold: in the RSVP, the valence of the earlier visual stimulus (the name of a person participants hate or love) would affect the magnitude of the attentional blink; seeing a name of a person people hate or love might activate feelings of hate or love which might also affect the magnitude of the attentional blink. Another goal of the current study is to explore whether individual differences in social value orientation and dark triad variables are related to the activation of the feeling of hate, or once activated, related to the intensity and duration of hate. Thus, we want to explore whether these personality variables would moderate activation of the feelings and moderate the effects of hate on the attentional blink.

Over the past few years, an increasing number of studies has focused on examining how prospective goals, such as action plans, can influence the way stimuli are encoded and maintained in working memory. Recently, it was shown that when a memorized stimulus is the direct target of an action, its visual working memory (VWM) representation is strengthened (Trentin et al., under review). However, it remains unclear whether for this strengthening to occur, it is sufficient to intend to act on a stimulus (i.e., select it as a target), or whether it is also necessary to know precisely how to act on it. That is, it is not understood if a prospective action needs to be well-defined for it to influence working memory representations. With this study, we aim to address this outstanding question. Specifically, we will test if linking a VWM representation to a defined action plan renders it stronger than linking it to an undefined action plan. To test this hypothesis, we will rely on an attentional capture paradigm, consisting of a visual selection task embedded within a prospective memory task. On each trial, participants will memorize a geometric shape and their memory of it will be subsequently tested. In the memory test, participants will be asked to act on the probe if it matches the memorized shape. In the defined-action condition, they will know how to act on it at encoding, while in the undefined-action condition, they will be informed about the action to be executed only right before the memory test is presented. In between the presentation of the stimulus to be memorized and the memory test, a visual selection task will be administered. Participants have to find a target as fast as possible by means of a saccade. Crucially, the memorized shape will always be present in the visual selection task, either surrounding the target (valid trials) or the distractor (invalid trials). We will assess the differences in strength of the VWM representations between the two conditions by evaluating the attentional biases induced by the shape held in VWM on the visual selection task.

This project shows that filtering and robust detrending can cause artifacts in temporal generalization matrices. Trial-masked robust detrending is free from such artefacts.

Beach safety flags form an internationally adopted warning system intended to prevent adverse incidents, including drownings. However, little is known about people's familiarity with these flags. In this study we tested the recognition and understanding of beach warning flags in the Netherlands, a country which welcomes millions of beach visitors every year. A convenience sample (N = 174) of the Dutch population was interviewed using a structured survey which asked for the meaning of eight different flags, the respondents’ confidence in their choice, as well as their intention with regard to entering the water. The results show an overall poor understanding of the meaning of all flags except for the red flags (which indicate high hazard). The level of confidence largely followed the same pattern, with low confidence for most flags except the red ones. Strikingly, the yellow flag (which indicates potential hazard and is meant to discourage bathing) evoked a considerable proportion of opposite associations (i.e., safety), combined with moderately high confidence and intentions to enter the water. More people were in fact inclined to enter the water under a yellow flag than under a red & yellow flag (which indicates a patrolled beach). Direct or indirect experience with danger in the sea did not affect people's knowledge of the flags but did reduce the intention to enter the water. We conclude that familiarity with the flag system in the Netherlands is wanting and we propose a number of recommendations to improve public understanding.

Item does not contain fulltext Models of biased competition assume that pre-activating a visual representation in visual working memory (VWM) biases perception towards memory-matching objects. Consistent with this, it has been shown that targets suppressed by interocular competition gain prioritized access to awareness when they match VWM content. Thus far, these VWM biases during interocular suppression have been investigated with minimal levels of competition, as there was always only one target stimulus and observers only held a single item in VWM. In the current study we investigated how VWM-based modulation of access to awareness is influenced by a) multiple-item competition within the stimulus display and b) multiple-item competition within VWM. Using the method of breaking continuous flash suppression (b-CFS), we replicated the finding that information matching the content of VWM is released from interocular suppression faster than non-matching information. This VWM-based facilitation was significantly reduced, though still present, when VWM load increased from one to two items, demonstrating a clear competitive constraint on the top-down modulation by VWM. Furthermore, we manipulated inter-stimulus competition by varying the presence of distractors. When distractors were present, VWM-based facilitation was no longer specific to interocular suppression, but also occurred for monocular displays. The results demonstrate that VWM-based visual biases occur in response to competition, whether between or within the eyes, and reconcile findings from different paradigms. 8 p.

Maintaining information in visual working memory (VWM) biases attentional selection of concurrent visual input, by favoring VWM-matching over VWM-mismatching visual input. Recently, it was shown that this bias disappears when the same item is memorized on consecutive occasions (as memoranda presumably transit from VWM to long-term memory), but reemerges when observers anticipate to memorize a novel item on a subsequent trial. Here, we aimed to conceptually replicate and extend this intriguing finding, by investigating whether prospectively reinstated memory drives conscious access of memory-matching visual input. We measured the time it took for participants to detect interocularly suppressed target stimuli, which were either from the same color category as a concurrently memorized color or not. our results showed that the advantage of memory-matching targets in overcoming suppression progresses non-monotonically across consecutive memorizations of the same color (‘repetitions’): the advantage for memory-matching visual input initially declined to asymptote, before being fully revived on the last repetition. this revival was not observed in a control experiment in which targets were not interocularly suppressed. the results suggest that, as observers anticipate to memorize a novel item imminently, VWM usage is prospectively reinstated, causing memory-matching visual input to gain accelerated access to consciousness again.

Maintaining information in visual working memory (VWM) biases attentional selection of concurrent visual input, by favoring VWM-matching over VWM-mismatching visual input. Recently, it was shown that this bias disappears when the same item is memorized on consecutive occasions (as memoranda presumably transit from VWM to long-term memory), but reemerges when observers anticipate to memorize a novel item on a subsequent trial. Here, we aimed to conceptually replicate and extend this intriguing finding, by investigating whether prospectively reinstated memory drives conscious access of memory-matching visual input. We measured the time it took for participants to detect interocularly suppressed target stimuli, which were either from the same color category as a concurrently memorized color or not. our results showed that the advantage of memory-matching targets in overcoming suppression progresses non-monotonically across consecutive memorizations of the same color (‘repetitions’): the advantage for memory-matching visual input initially declined to asymptote, before being fully revived on the last repetition. this revival was not observed in a control experiment in which targets were not interocularly suppressed. the results suggest that, as observers anticipate to memorize a novel item imminently, VWM usage is prospectively reinstated, causing memory-matching visual input to gain accelerated access to consciousness again.

In the research literature, attention and working memory are often intimately linked. In his excellent target article, Oberauer concludes that attention is not a necessary requirement for working memory maintenance. In our reply, we argue that attention is an emergent property of maintaining the current task goal. Humans can flexibly transfer the storage of information between different states and different memory systems as the need arises. Only information in service of currently active task goals requires attentional resources for maintenance. In this state, memoranda can bias behavior and are susceptible to interference from additional attention demanding tasks.

This Article contains an error in the legend of Figure 6. “Decoding accuracy in Experiment 2. (A) 8-way classification accuracy of target position (chance = 0.125). The black line reflects significance at p < 10−3 (cluster based permutation test), shaded area is +/− s.e.m. Peak at 264 ms. Note again the similarity in temporal evolution with the N2pc (Fig. 3) and decoding accuracies of Experiment 1 (Fig. 4), although plausibly peaking slightly later because of the increase in the number of items on the screen. (B) Classsification accuracy per quadrant (chance = 0.5). (C) Separate N2pc components were computed for left versus right target objects at each of the four vertical elevations, indicated by color. Colored sections indicate p < 10−3 (cluster based permutation test).” should read: “Comparing the N2pc to decoding accuracy in Experiment 2. (A) Average N2pc for left and right targets in Experiment 2, computed using PO7 and PO8 (see Methods). Peak at 260 ms. (B) 8-way classification accuracy of target position in Experiment 2 (chance = 0.125). Peak at 264 ms. Note again the similarity in temporal evolution of decoding accuracy in panel B when compared to the temporal evolution of the N2pc in panel A. (C) Separate N2pc components at each of the four vertical elevations, indicated by color. Thick black or colored lines reflect significance at p < 10−3 (cluster based permutation test), shaded areas are +/− s.e.m.”.

A cornerstone of the target article is that, in a predictive coding framework, attention can be modelled by weighting prediction error with a measure of precision. We argue that this is not a complete explanation, especially in the light of ERP (event-related potentials) data showing large evoked responses for frequently presented target stimuli, which thus are predicted.

The present dissertation took the free-energy principle (FEP) as its starting point, from which we tried to draw both philosophical and empirical consequences. Both chapter 2 and 3 departed from the idea that conscious perception depends on global amplification of sensory input, and that the basal ganglia (BG) and its irrigation by dopamine play a crucial role in gating information, conscious access, and the selection of a relevant internal model given available sensory data. The BG are thought to play this role due to their modulatory influence on thalamocortical connectivity. Because much of the evidence implicating the BG in these processes in humans is correlational, we explored two ways of manipulating BG activity experimentally. Chapter 4 investigates the philosophical heritage implicitly touched on by the FEP, which provides an alternative philosophical and historical background for present-day research in cognitive neuroscience. Friston’s FEP has been received with great enthusiasm. With good reason: it not only makes the bold claim to a unifying theory of the brain, but it is presented as an a priori principle applicable to living systems in general. In this paper, we set out to show how the breadth of scope of Friston’s framework converges with the dialectics of Georg Hegel. Through an appeal to the work of Catherine Malabou, we aimed to demonstrate how Friston not only reinvigorates Hegelian dialectics from the perspective of neuroscience, but that the implicit alignment with Hegel necessitates a reading of the FEP from the perspective of Hegel’s speculative philosophy. It is this reading that moves beyond the discussion between cognitivism and enactivism surrounding Friston’s framework; beyond the question whether the organism is a secluded entity separated from its surroundings, or whether it is a dynamical system characterized by perpetual openness and mutual exchange. From a Hegelian perspective, it is the tension between both positions itself that is operative at the level of the organism; as a contradiction the organism sustains over the course of its life. Not only does the organism’s secluded existence depend on a perpetual relation with its surroundings, but the condition for there to be such a relation is the existence of a secluded entity. We intended to show how this contradiction – tension internalized – is at the center of Friston’s anticipatory organism; how it is this contradiction that grounds the perpetual process of free energy minimization. Chapter 5 is the report of a study attempting to contrast the FEP’s perspective with that of traditional cognitive neuroscience. While the FEP casts the brain as an organism’s predictive model of how its world works and will continue to work in the future in which action is afforded a central place, research on the brain’s predictive capacities remains beholden to traditional research practices in which participants are passively shown stimuli without their active involvement (as we also did in Chapters 2 and 3). 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 (externally/cue-induced, internally/action-induced) 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.

Holistic processing (HP) of faces is usually measured by the composite effect. While Weston and Perfect [2005. Effects of processing bias on the recognition of composite face halves. Psychonomic Bulletin & Review, 12, 1038–1042. doi:10.3758/BF03206440] found that priming at the local level speeded recognition of components of faces, Gao et al. [2011. Priming global and local processing of composite faces: Revisiting the processing-bias effect on face perception. Attention Perception & Psychophysics, 73, 1477–1486. doi:10.3758/s13414-011-0109-7] found that only global priming had an effect on HP of faces. The two studies used different versions of the composite task (the partial design, which is considered to be prone on bias, and the complete design). However, the two studies also differed in other respects and it is difficult to know to what extent issues with the partial design contributed to the differing conclusions. In the present study, the HP indexed by the complete design measure was augmented by global priming. In contrast, no effect was observed in the partial design index. We claim that the partial design index reflects other factors besides HP, including response bias, and conclude that HP can be understood within the context of domain-general attentional processes.

Are face recognition difficulties in Autism Spectrum Disorders (ASD) related to impaired holistic processing? Gauthier et al. [Gauthier, I., Klaiman, C., & Schultz, R. T. (2009). Face composite effects reveal abnormal face processing in Autism spectrum disorders. Vision Research, 49, 470–478. doi:10.1016/j.visres.2008.12.007] used the face composite task in adolescents with autism and found a congruency effect that was not modulated by alignment, a result which was interpreted as reflecting qualitatively different face processing mechanisms. In the present study we tested adults with ASD in a composite face task where presentation times were manipulated and further explored whether these participants were sensitive to holistic information in faces using a new version of the composite task: VHFPT 2.0 (The Vanderbilt Holistic Face Processing Test 2.0). Results suggest that adults with ASD process faces holistically and that their facial identity processing abilities are qualitatively similar and as ...