According to a popular strategy amongst economists and philosophers, in order to solve the problem of interpersonal utility comparisons, we have to look at how ordinary people make such comparisons in everyday life. The most recent attempt to develop this strategy has been put forward by Goldman in his “Simulation and Interpersonal Utility” (Ethics 4:709–726, 1995). Goldman claims, first, that ordinary people make interpersonal comparisons by simulation and, second, that simulation is reliable for making interpersonal comparisons. In this paper, I (...) focus on Goldman’s latter claim. After updating Goldman’s account of how ordinary people make interpersonal comparisons in the light of Goldman’s newest formulation of his simulation theory of mental ascription (Goldman, Simulating Minds. Oxford University Press, Oxford, 2006), I develop and assess Goldman’s arguments in favour of the reliability of simulation for interpersonal comparisons. I argue that, under certain conditions, there may be room for a scientifically acceptable solution to the problem of interpersonal utility comparisons. (shrink)

Problems are raised with the global workspace hypothesis of consciousness, for example about exactly how global the workspace needs to be for consciousness to suddenly be present. Problems are also raised with Carruthers's version that excludes conceptual representations, and in which phenomenal consciousness can be reduced to physical processes, with instead a different levels of explanation approach to the relation between the brain and the mind advocated. A different theory of phenomenal consciousness is described, in which there is a particular (...) computational system involved in which Higher Order Syntactic Thoughts are used to perform credit assignment on first order thoughts of multiple step plans to correct them by manipulating symbols in a syntactic type of working memory. This provides a good evolutionary reason for the evolution of this kind of computational module, with which, it is proposed, phenomenal consciousness is associated. Some advantages of this HOST approach to phenomenal consciousness are then described with reference not only to the global workspace approach, but also to Higher Order Thought theories. It is hypothesized that the HOST system which requires the ability to manipulate first order symbols in working memory might utilize parts of the prefrontal cortex implicated in working memory, and especially the left inferior frontal gyrus, which is involved in language and probably syntactical processing. Overall, the approach advocated is to identify the computations that are linked to consciousness, and to analyze the neural bases of those computations. [copyright: Copyright © 2020 Rolls.]. (shrink)

Although complex hallucinations are extremely vivid, painful symptoms in schizophrenia, little is known about the underlying mechanisms of multisensory integration in such a phenomenon. We investigated the neural basis of these altered states of consciousness in a patient with schizophrenia, by combining state of the art neuroscientific exploratory methods like functional MRI, diffusion tensor imaging, cortical thickness analysis, electrical source reconstruction and trans-cranial magnetic stimulation. The results shed light on the functional architecture of the hallucinatory processes, in which unimodal information (...) from different modalities is strongly functionally connected to higher-order integrative areas. (shrink)

People can maintain accurate representations of visual changes without necessarily being aware of them. Here, we investigate whether a similar phenomenon also exists in touch. In Experiments 1 and 2, participants detected the presence of a change between two consecutively-presented tactile displays. Tactile change blindness was observed, with participants failing to report the presence of tactile change. Critically, however, when participants had to make a forced choice response regarding the number of stimuli presented in the two displays, their performance was (...) significantly better than chance . Experiment 3 demonstrated that tactile change detection does not necessarily involve a shift of spatial attention toward the location of change, regardless of whether the change is explicitly detected. We conclude that tactile change detection likely results from comparing representations of the two displays, rather than by directing spatial attention to the location of the change. (shrink)

How must experience of time be structured in time? In particular, does the following principle, which I will call inheritance, hold: for any temporal property apparently presented in perceptual experience, experience itself has that same temporal property. For instance, if I hear Paul McCartney singing ‘Hey Jude’, must my auditory experience of the ‘Hey’ itself precede my auditory experience of the ‘Jude’, or can the temporal order of these experiences come apart from the order the words are experienced as having? (...) A number of recent authors (Phillips Experience and Time, ‘The Temporal Structure of Experience’, Soteriou ‘Perceiving Events’, Hoerl ‘“A Succession of Feelings, in and of Itself, is Not a Feeling of Succession”’, Rashbrook) claim, to paraphrase Martin (399), that inheritance best characterises how our temporal experience seems to initial reflective intuition. For this reason, Phillips takes the principle to form part of our naïve view of temporal experience. An opposing group of theorists object that inheritance is subject to empirical counter-example. This article surveys such challenges. Section 2 considers Grush's case against inheritance based on postdiction. Section 3 examines Watzl's anti-inheritance argument based on silencing effects. Finally, Section 4 explores a number of alleged counter-examples proposed by Lee (‘Temporal Experience and the Temporal Structure of Experience’). Section 1 provides essential background to the debate. (shrink)

The naïve view of temporal experience (Phillips, in: Lloyd D, Arstila V (eds) Subjective time: the philosophy, psychology, and neuroscience of temporality, forthcoming-a) comprises two claims. First, that we are perceptually aware of temporal properties, such as succession and change. Second, that for any temporal property apparently presented in experience, our experience itself possesses that temporal property. In his paper ‘Silencing the experience of change’ (forthcoming), Watzl argues that this second naïve inheritance thesis faces a novel counter-example in the form (...) of the striking motion silencing effects recently demonstrated by Suchow and Alvarez (Curr Biol 21(2):140–143, 2011). Here I clarify the form which any counter-example to naïve inheritance must take. I then explain how, on a plausible, rival ‘crowding’ interpretation of Suchow and Alvarez’s data, motion silencing poses no more of a threat to naïve inheritance than standard cases of change blindness. (shrink)

Following arguments put forward in my book (Why red doesn’t sound like a bell: understanding the feel of consciousness. Oxford University Press, New York, USA, 2011), this article takes a pragmatic, scientist’s point of view about the concepts of consciousness and “feel”, pinning down what people generally mean when they talk about these concepts, and then investigating to what extent these capacities could be implemented in non-biological machines. Although the question of “feel”, or “phenomenal consciousness” as it is called by (...) some philosophers, is generally considered to be the “hard” problem of consciousness, the article shows that by taking a “sensorimotor” approach, the difficulties can be overcome. What remains to account for are the notions of so-called “access consciousness” and the self. I claim that though they are undoubtedly very difficult, these are not logically impossible to implement in robots. (shrink)

Contextual regularities, that is, objects’ tendency to appear with certain other objects, facilitate the processing of visual scenes and confer contextually incongruent objects with a special attentional status. This study was aimed at investigating the mechanisms underlying this attentional advantage using Binocular Rivalry . In two experiments, congruent and incongruent images were pitted against each other, yielding a version of BR in which two objects rival within a given scene. Incongruent objects predominated in awareness longer than congruent ones. This effect (...) stemmed from the fact that their dominance epochs lasted longer on the average than those of congruent objects, suggesting a difficulty to disengage attention from such objects. On the other hand, no support was found for the notion that incongruent objects also attract attention. (shrink)

Recent research indicates that interpersonal communication is noisy, and that people exhibit considerable insensitivity to problems in communication. Using a dyadic referential communication task, the goal of which is accurate information transfer, this study examined the extent to which interlocutors are sensitive to problems in communication and use other‐initiated repairs (OIRs) to address them. Participants were randomly assigned to dyads (N = 88 participants, or 44 dyads) and tried to communicate a series of recurring abstract geometric shapes to a partner (...) across a text–chat interface. Participants alternated between directing (describing shapes) and matching (interpreting shape descriptions) roles across 72 trials of the task. Replicating prior research, over repeated social interactions communication success improved and the shape descriptions became increasingly efficient. In addition, confidence in having successfully communicated the different shapes increased over trials. Importantly, matchers were less confident on trials in which communication was unsuccessful, communication success was lower on trials that contained an OIR compared to those that did not contain an OIR, and OIR trials were associated with lower Director Confidence. This pattern of results demonstrates that (a) interlocutors exhibit (a degree of) sensitivity to problems in communication, (b) they appropriately use OIRs to address problems in communication, and (c) OIRs signal problems in communication. (shrink)

Previous research demonstrates that implicitly learned probability information can guide visual attention. We examined whether the probability of an object changing can be implicitly learned and then used to improve change detection performance. In a series of six experiments, participants completed 120–130 training change detection trials. In four of the experiments the object that changed color was the same shape on every trial. Participants were not explicitly aware of this change probability manipulation and change detection performance was not improved for (...) the trained shape versus untrained shapes. In two of the experiments, the object that changed color was always in the same general location . Although participants were not explicitly aware of the change probability, implicit knowledge of it did improve change detection performance in the trained location. These results indicate that improved change detection performance through implicitly learned change probability occurs for location but not shape. (shrink)

The present paper was written as a contribution to ongoing methodological debates within the NCC project. We focus on the neural correlates of conscious perceptual episodes. Our claim is that the NCC notion, as applied to conscious perceptual episodes, needs to be reconceptualized. It mixes together the processing related to the perceived contents and the neural substrate of consciousness proper, i.e. mechanisms making the perceptual contents conscious. We thus propose that the perceptual NCC be divided into two constitutive subnotions. The (...) main theoretical idea that emerges as a consequence of this reconceptualization is that the neural correlate of a perceptual episode is formed in the neural interaction between content-processing and consciousness-conferring mechanisms. The paper elaborates this distinction, marshals some initial arguments in its favour, and tests it against some of the most debated theories of consciousness. (shrink)

The paper aims to defend the standard view of what it dubs ‘Self-understanding' — i.e., (very roughly) our knowledge of why we behave as we do — from the threat posed to it by Neo-Ryleanism. While the standard, entrenched view regards self-understanding as special in kind and status, the Neo-Rylean agrees with Gilbert Ryle that our method of understanding ourselves is much the same as our method of understanding others, involving self-interpretation on the basis of the available evidence. Neo-Ryleanism has (...) been gaining ground in recent decades, fueled by a wide range of empirical results which allegedly demonstrate that subjects confabulate items of self-understanding. The paper rejects this attack on the received view. After critically examining one extant response to the Neo-Rylean, which gratuitously accuses her of equivocation, the paper proceeds to offer its own response, casting doubt over the suggestion that the experimental results actually demonstrate widespread confabulation. (shrink)

The idea that attention is necessary for consciousness (the “Necessity Thesis”) is frequently advocated by philosophers and psychologists alike. Experiments involving inattentional and change blindness are thought to support the Necessity Thesis, but they do so only if subjects failing to notice the target stimulus are also not conscious of it. This article uses commonsense phenomenological observations supplemented with empirical data to argue that some subjects failing to notice the target stimulus nonetheless experience its color. Since subjects not noticing the (...) target are commonly assumed to be not attending to it, these scenarios would be instances of consciousness without attention: instead of inattentional and change blindness supporting the Necessity Thesis, they would present counterexamples to it. (shrink)

Some proponents of the higher-order thought theory of consciousness defend the view that higher-order misrepresentation is possible. In support of this view they have proposed various pieces of empirical evidence. This paper examines one such piece of proposed empirical evidence; Change blindness. CB occurs when a subject fails to detect salient changes in visual scenes. I propose an alternative interpretation of the CB phenomenon on which misrepresentation does not occur. Finally, I examine three lines of reply that might be pursued (...) to defend the claim that CB is evidence of misrepresentation against my interpretation. I conclude that none of the lines of reply succeed in preserving CB as evidence of misrepresentation. The upshot is that, pending further evidence, CB cannot be deployed as empirical evidence in the debate on misrepresentation. (shrink)

A commentary on: Seeing changes: How familiarity alters our perception of change by Tovey, M., and Herdman, C. (2014). Vis. Cogn. 22, 214–238 .

Studies in cognitive psychology have shown that the deployment of visual attention operates under spatial limitations, rendering its assignment to multiple locations difficult or costly. This study explored whether this conventional understanding applies to human metaattention as well. I measured the spatial distribution of metaattention during viewing of natural scenes and found that participants believed they could attend to multiple locations simultaneously. Study 2 tested whether this tendency could be modified by information about the tendency to overestimation. After participants were (...) informed of this tendency toward overestimation with both verbal instruction and demonstrations of attentional blindness and blindness to these phenomena, the selectivity of metaattention increased. Study 3 demonstrated that participants overestimated their attentional abilities by comparing the metaattentional drawings and the actual behavioral performances of the same participants. These results were consistent with recent findings of metaattentional overestimation in change detection and suggested human insensitivity in monitoring attentional limitations. (shrink)

This paper discusses possible correspondences between neuroscientific findings and phenomenologically informed methodologies in the investigation of kinesthetic empathy in watching dance. Interest in phenomenology has recently increased in cognitive science (Gallagher and Zahavi 2008 ) and dance scholars have recently contributed important new insights into the use of phenomenology in dance studies (e.g. Legrand and Ravn (Phenomenology and the Cognitive Sciences 8(3):389–408, 2009 ); Parviainen (Dance Research Journal 34(1):11–26, 2002 ); Rothfield (Topoi 24:43–53, 2005 )). In vision research, coherent neural (...) mechanisms for perceptual phenomena were uncovered, thus supporting correlation of phenomenology and neurophysiology Spillmann (Vision Research 49(12):1507–1521, 2009 ). Correspondingly, correlating subjects’ neurophysiological data with qualitative responses has been proposed as a means to research the human brain in the study of consciousness (Gallagher and Zahavi 2008 ), with similar issues in clinical psychology Mishara (Current Opinion in Psychiatry 20(6):559–569, 2007 ) and biology Kosslyn et al. (American Psychologist 57:341–351, 2002 ). Yet the relationship between neuroscience and qualitative research informed by phenomenology remains problematic. How qualitative research normally handles subjective experiences is difficult to reconcile with standard statistical analysis of objective data. Recent technological developments in cognitive neuroscience have inspired a number of researchers to use more naturalistic stimuli, outside the laboratory environment, such as dance, thereby perhaps helping to open up the cognitive sciences to more phenomenologically informed approaches. A question central to our research, addressed here, is how the phenomenal experiences of a dance audience member, as accessed by qualitative research methods, can be related to underlying neurophysiological events. We outline below some methodological challenges encountered in relating audiences’ first-person accounts of watching live dance performance to neurophysiological evidence of their experiences. (shrink)

Consciousness is now a hot topic in both philosophy and the cognitive sciences, yet there is much controversy over how to measure it. First, it is not clear whether biased subjective reports should be taken as adequate for measuring consciousness, or if more objective measures are required. Ways to benefit from the advantages of both these measures in the form of ‘Type 2’ metacognitive measures are under development, but face criticism. Research into neurophysiological measures of consciousness is potentially very valuable, (...) but often hindered by its dependence on behavioural measures that are themselves controversial. Newer informational measures are theoretically interesting, but as yet not easily applicable, while other measures of consciousness are designed for application in clinical cases . Although much optimism accompanies research into measures of consciousness, the controversies and methodological problems reviewed here suggest that making progress in this area may be more difficult than is often acknowledged. (shrink)

Introspective and phenomenological methods are once again being used to support the use of subjective reports, rather than objective behavioural measures, to investigate and measure consciousness. Objective measures are often seen as useful ways of investigating the range of capacities subjects have in responding to phenomena, but are fraught with the interpretive problems of how to link behavioural capacities with consciousness. Instead, gathering subjective reports is seen as a more direct way of assessing the contents of consciousness. This article explores (...) three different ways of gathering subjective reports that have been discussed in recent literature on consciousness, including immediate retrospection (Schwitzgebel [2007]) and two types of introspective training (Overgaard et al. [2004]; Schwitzgebel [2008]). Although not an exhaustive survey of the range of introspective methods now used, the discussion below highlights a range of general methodological problems with introspective methods, many identified up to a century ago. It is argued that none of the methodological problems established in earlier criticisms of the use of subjective reports have been dealt with, yet are still valid criticisms. Given that this is not the first time proponents of introspective, subjective measures of conscious have failed to answer these criticisms, this raises the question of whether the goal of providing a measure of consciousness is a methodological muddle worth pursuing. (shrink)

The Hard Problem is surrounded by a vast literature, to which it is increasingly hard to contribute to in any meaningful way. Accordingly, the strategy here is not to offer any new metaphysical or ‘in principle’ arguments in favour of the success of materialism, but to assume a Type Q(uinian) approach and look to contemporary consciousness science to see how the concept of consciousness fares there, and what kind of explanations we can hope to offer of it. It is suggested (...) that while they will be materialist explanations, they will not be of the form that many scientists and philosophers would have us believe, but instead prompt a very different set of expectations and research projects. (shrink)

There is a long standing debate as to whether or not time is ‘real’ or illusory, and whether or not human time is a direct reflection of physical time. Differing spacetime cosmologies have opposing views. Exactly what human time entails has, in our opinion, led to the failure to resolve this ‘two times’ problem. To help resolve this issue we propose a dualistic model of human time in which each component has both an illusory and non-illusory aspect. With the dualistic (...) model we are able to provide experimental tests for all of the human time assertions of 10 chosen spacetime cosmologies. The illusory aspect of the ‘present,’ i.e. a ‘unique present’ was confirmed. An information gathering and utilizing system was constructed using a virtual reality apparatus allowing the observer to experientially roam back and forth along the worldline ad lib. The phenomenon of ‘change’ was experimentally found to be illusory at high frequency observation and non-illusory at low frequency observation, the latter phenomenon coinciding with ‘change’ referred to in the ‘Order of Time’ and ‘Relativity Refounded’ views. Additional experiments are presented indicating that both motion and temporality are dualistic. In sum, the dualistic model of human time allows for the existence of both illusory and non-illusory aspects of human time that are not in conflict with one another. It also provides experimental evidence for various spacetime cosmological assertions regarding human time. (shrink)

Does perceptual consciousness require cognitive access? Ned Block argues that it does not. Central to his case are visual memory experiments that employ post-stimulus cueing—in particular, Sperling's classic partial report studies, change-detection work by Lamme and colleagues, and a recent paper by Bronfman and colleagues that exploits our perception of ‘gist’ properties. We argue contra Block that these experiments do not support his claim. Our reinterpretations differ from previous critics' in challenging as well a longstanding and common view of visual (...) memory as involving declining capacity across a series of stores. We conclude by discussing the relation of probabilistic perceptual representations and phenomenal consciousness. (shrink)

Attentional scanning was studied in anxious and non-anxious participants, using a modified change detection paradigm. Participants detected changes in pairs of emotional scenes separated by two task irrelevant slides, which contained an emotionally valenced scene and a visual mask. In agreement with attentional control theory, change detection latencies were slower overall for anxious participants. Change detection in anxious, but not non-anxious, participants was influenced by the emotional valence and exposure duration of distractor scenes. When negative distractor scenes were presented at (...) subliminal exposure durations, anxious participants detected changes more rapidly than when supraliminal negative scenes or subliminal positive scenes were presented. We propose that for anxious participants, subliminal presentation of emotionally negative distractor scenes stimulated attention into a dynamic state in the absence of attentional engagement. Presentation of the same scenes at longer exposure times was accompanied by conscious awareness, attentional engagement, and slower change detection. (shrink)

In a series of four experiments, we examine the hypothesis that selective attention is crucial for the generation of conscious knowledge of contingency information. We investigated this question using a spatial priming task in which participants were required to localize a target letter in a probe display. In Experiment 1, participants kept track of the frequency with which the predictive letter in the prime appeared in various locations. This manipulation had a negligible impact on contingency awareness. Subsequent experiments requiring participants (...) to attend to features of the predictive letter increased contingency awareness somewhat, but there remained a large proportion of individuals who remained unaware of the strong contingency. Together the results of our experiments suggest that the construct of attention does not fully capture the processes that lead to contingency awareness, and suggest a critical role for bottom-up feature integration in explicit contingency learning. (shrink)

Patients suffering from the behavioral variant of Frontotemporal Dementia (FTD-b) often exaggerate their abilities. Are those errors in judgment limited to domains in which patients under-perform, or do FTD-b patients overestimate their abilities in other domains? Is overconfidence in FTD-b patients domain-specific or domain-general? To address this question, we asked patients at early stages of FTD-b to judge their performance in two domains (attention, perception) in which they exhibit relatively spared abilities. In both domains, FTD-b patients overestimated their performance relative (...) to patients with Dementia of Alzheimer Type (DAT) and healthy elderly subjects. Results are consistent with a domaingeneral deficit in metacognitive judgment. We discuss these findings in relation to “regression to the mean” accounts of overconfidence and the role of emotions in metacognitive judgments. (shrink)

The cognitive sciences tell us that the self is a construct. The visual arts illustrate this fact. Mathematics give it full expression, abstracting the self to a Grothendieck site. This self is a haecceity, an ephemeral this-ness and now-ness. We make up our minds and our histories. That our acts are public, that they communicate effectively, becomes a dialetheic paradox, a deep paradox for our times.

The Emergic Cognitive Model (ECM) is a unified computational model of visual filling-in based on the Emergic Network architecture. The Emergic Network was designed to help realize systems undergoing continuous change. In this thesis, eight different filling-in phenomena are demonstrated under a regime of continuous eye movement (and under static eye conditions as well). -/- ECM indirectly demonstrates the power of unification inherent with Emergic Networks when cognition is decomposed according to finer-grained functions supporting change. These can interact to raise (...) additional emergent behaviours via cognitive re-use, hence the Emergic prefix throughout. Nevertheless, the model is robust and parameter free. Differential re-use occurs in the nature of model interaction with a particular testing paradigm. -/- ECM has a novel decomposition due to the requirements of handling motion and of supporting unified modelling via finer functional grains. The breadth of phenomenal behaviour covered is largely to lend credence to our novel decomposition. -/- The Emergic Network architecture is a hybrid between classical connectionism and classical computationalism that facilitates the construction of unified cognitive models. It helps cutting up of functionalism into finer-grains distributed over space (by harnessing massive recurrence) and over time (by harnessing continuous change), yet simplifies by using standard computer code to focus on the interaction of information flows. Thus while the structure of the network looks neurocentric, the dynamics are best understood in flowcentric terms. Surprisingly, dynamic system analysis (as usually understood) is not involved. An Emergic Network is engineered much like straightforward software or hardware systems that deal with continuously varying inputs. Ultimately, this thesis addresses the problem of reduction and induction over complex systems, and the Emergic Network architecture is merely a tool to assist in this epistemic endeavour. -/- ECM is strictly a sensory model and apart from perception, yet it is informed by phenomenology. It addresses the attribution problem of how much of a phenomenon is best explained at a sensory level of analysis, rather than at a perceptual one. As the causal information flows are stable under eye movement, we hypothesize that they are the locus of consciousness, howsoever it is ultimately realized. (shrink)

in Encyclopedia of Consciousness, ed. William P. Banks, Amsterdam: Elsevier, forthcoming in 2009.

An overview is presented of the ways that change blindness has been applied to the study of various issues in perception and cognition. Topics include mechanisms of change perception, allocation of attention, nonconscious perception, and cognitive beliefs. Recent work using change blindness to investigate these topics is surveyed, along with a brief discussion of some of the ways that these approaches may further develop over the next few years.

In this article, I examine a new concept of “Twin Memory’ which has emerged in memory classification research of conscious and unconscious memory representations. It is to analyse the presence of twin memory among the various memory systems, and also to provide a platform for the twin memory “anatomy” in the field of cognitive science, neuropsychology and neuroscience.

In this article a concept of non-local consciousness will be described, based on recent scientific research on near-death experiences . Since the publication of several prospective studies on NDEs in survivors of cardiac arrest, with strikingly similar results and conclusions, the phenomenon of the NDE can no longer be scientifically ignored. In the last thirty years several theories have been proposed to explain an NDE. The challenge to find a common explanation for the cause and content of an NDE is (...) complicated by the fact that an NDE can be experienced during various circumstances, such as severe injury of the brain as in cardiac arrest to conditions when the brain seems to function normally. The NDE is an authentic experience which cannot be simply reduced to imagination, fear of death, hallucination, psychosis, the use of drugs, or oxygen deficiency. Patients appear to be permanently changed by an NDE during a cardiac arrest of only some minutes duration. According to these aforementioned studies, the current materialistic view of the relationship between consciousness and the brain as held by most physicians, philosophers, and psychologists is too restricted for a proper understanding of this phenomenon. There are good reasons to assume that our consciousness does not always coincide with the functioning of our brain: enhanced or non-local consciousness can sometimes be experienced separately from the body. (shrink)

The present work shows the existence of systematic individual differences in change blindness. It can be concluded that the sensitivity for changes is a trait. That is, persons differ in their ability to detect changes, independent from the situation or the measurement method. Moreover, there are two explanations for individual differences in change blindness: a) capacity differences in visual selective attention that may be influenced by top-down activated attention helping to focus attention onto relevant stimuli b) differences in working memory (...) capacity or in decision making. In accordance with this, age-related individual differences in the sensitivity for changes can be explained by attentional processes and by confidence in the own ratings. Together, the present work might form the basis for a more application-oriented research on individual differences in change blindness and its underlying processes. (shrink)

Alva Noë’s version of the enactive conception in _Action in Perception_ is an important contribution to the study of visual perception. First, I argue, however, that it is unclear (at best) whether, as the enactivists claim, work on change blindness supports the denial of the existence of detailed visual representations. Second, I elaborate on what Noë calls the ‘puzzle of perceptual presence’. Thirdly, I question the enactivist account of perceptual constancy. Finally, I draw attention to the tensions between enactivism and (...) two trends in cognitive neuroscience: the two-visual systems model of human vision and the theory of internal forward models of action. (shrink)

The present work is concerned with a phenomenon referred to as contextual cueing. In visual search, if a searched-for target object is consistently encountered within a stable spatial arrangement of distractor objects, detecting the target becomes more efficient over time, relative to non-repeated, random arrangements. This effect is attributed to learned target-distractor spatial associations stored in long-term memory, which expedite visual search. This Thesis investigates four aspects of contextual cueing: Study 1 tackled the implicit-explicit debate of contextual cueing from a (...) new perspective. Previous studies tested explicit access to learned displays by applying a recognition test, asking observers whether they have seen a given display in the previous search task. These tests, however, typically yield mixed findings and there is an on-going controversy whether contextual cueing can be described as an implicit or an explicit effect. The current study applied the new perspective of metacognition to contextual cueing and combined a contextual cueing task with metacognitive ratings about the clarity of the visual experience, either of the display configuration or the target stimulus. Bayesian analysis revealed that there was an effect of repeated context on metacognitive sensitivity for configuration, but not target, ratings. It was concluded that effects of contextual memory on metacognition are content-specific and lead to increased metacognitive access to the display configuration, but not to the target stimulus. The more general implication is that from the perspective of metacognition, contextual cueing can be considered as an explicit effect. Study 2 aimed at testing how explicit knowledge affects memory-guided visual search. Two sets of search displays were shown to participants: explicit and implicit displays. Explicit displays were introduced prior to the search experiment, in a dedicated learning session, and observers should deliberately learn these displays. Implicit displays, on the other hand, were first shown in the search experiment and learning was incidental through repeated exposure to these displays. Contextual cueing arising from explicit and implicit displays was assessed relative to a baseline condition of non-repeated displays. The results showed a standard contextual cueing effect for explicit displays and, interestingly, a negative cueing effect for implicit displays. Recognition performance was above chance for both types of repeated displays; however, it was higher for explicit displays. This pattern of results confirmed – in part – the predictions of a single memory model of attention-moderated associative learning, in which different display types compete for behavior and explicit representations block the retrieval of implicit representations. Study 3 investigates interactions between long-term contextual memory with short-term perceptual hypotheses. Both types of perceptual memory share high similarities with respect to their content, therefore the hypothesis was formulated that they share a common memory resource. In three experiments of interrupted search with repeated and non-repeated displays, it was shown that contextual cueing expedites performance in interrupted search; however, there was no interaction of contextual cueing with the generation or the confirmation of perceptual hypotheses. Rather, the analysis of fixational eye movements showed that long-term memory exerts its influence on search performance upon the first glance of a given display, essentially affecting the starting point of the search process. The behavior of approaching the target stimulus is then a product of generating and confirming perceptual hypotheses with these processes being unaffected by long-term contextual memory. It was concluded that long-term and short-term memory representations of the same search display are independent and exhibit additive effects on search performance. Study 4 is concerned with the effects of reward on perceptual learning. It was argued that rewarding repeated displays in a contextual cueing paradigm leads to an acceleration of the learning effect; however, it was not considered whether reward also has an effect in non-repeated displays. In these displays, at least the target position is kept constant while distractor configurations are random across repetitions. Usually this is done in order to account for target position-specific probability learning in contextual cueing. However, it is possible that probability learning itself is modulated by reward. The current experiment introduced high or low reward to repeated and importantly, also non-repeated displays. It was shown that reward had a huge effect on non-repeated displays, indicating that rewarding certain target positions, irrespective of the distractor layout, facilitates RT performance. Interestingly, reward effects were even larger for non-repeated compared to repeated displays. It was concluded that reward has a strong effect on probability-, and not context learning. (shrink)