Philosophers have usually approached the concept of timing of experiences by addressing the question how the experiences of temporal phenomena can be explained. As a result, the issue of timing has been addressed in two different ways. The first, similar to the questions posed in sciences, concerns the relationship between the experienced time of events and the objective time of events. The second approach is more specific to philosophers’ debates, and concerns the phenomenology of experiences: how is the apparent temporal (...) structure of experiences constituted? In regard to both questions, this article shows why and how philosophers’ views differ from those held by most scientists. To conclude, I present a combination of views that is not only compatible with that of scientists, but also addresses the problems that engage philosophers. (shrink)

According to unconscious perception hypothesis (UP), mental states of the same fundamental kind as ordinary conscious seeing can occur unconsciously. The proponents of UP often support it with empirical evidence for a more specific hypothesis, according to which colours can be seen unconsciously (UPC). However, UPC is a general claim that admits of many interpretations. The main aim of this paper is to determine which of them is the most plausible. To this end, I investigate how adopting various conceptions of (...) colour and perceptual phenomenal character affects UPC’s resilience to objections. This brings me to the conclusion that the most plausible reading of UPC is the one according to which the phenomenal character of colour perception (i) is constituted by colours qua primitive mind-independent qualities of the environment and (ii) is not essentially tied to consciousness. My conclusion not only identifies the most plausible interpretation of UPC, but also highlights and supports an unorthodox version of the relational theory of perception, which is a perfectly viable yet so far overlooked stance in the debate about unconscious perception. (shrink)

In the contemporary discussions concerning unconscious perception it is not uncommon to postulate that content and phenomenal character are ‘orthogonal’, i.e., there is no type of content which is essentially conscious, but instead, every representational content can be either conscious or not. Furthermore, this is not merely treated as a thesis justified by theoretical investigations, but as supported by empirical considerations concerning the actual functioning of the human cognition. In this paper, I address unconscious color perception and argue for a (...) negative thesis—that the main experimental paradigms used in studying unconscious color perception do not provide support for the position that conscious and unconscious color representations have the same type of content. More specifically, I claim that there is no significant support for the claim that unconscious vision categorically represents surface colors. (shrink)

Dennett and Kinsbourne ([1992]) argue that metacontrast backward visual masking provides a clear illustration that ‘there is really only a verbal difference’ between two versions of the Cartesian Theater model of the mind. This alleged lack of a distinction is both the crucial premise of their main argument against the Cartesian Theater and a motivator for accepting their own Multiple Drafts model. I argue that metacontrast reveals a difference between the two versions of the Cartesian Theater that meets criteria found (...) in (Dennett and Kinsbourne [1992]) for determining such a difference. This difference undermines the soundness of their argument against the Cartesian Theater, and exerts pressure on Dennett and Kinsbourne to offer a more detailed articulation of their model. 1. Introduction2. Brief Explanation of Metacontrast Backward Visual Masking3. The Stalinesque and Orwellian Models of Metacontrast 3.1. Criteria for determining a difference4. A Difference That Makes a Difference 4.1. Skeptical hypothesis objection5. Other Objections and Replies 5.1. Straw person objection5.2. Corroborative issues objection6. Conclusion. (shrink)

In my dissertation I critically survey existing theories of time consciousness, and draw on recent work in neuroscience and philosophy to develop an original theory. My view depends on a novel account of temporal perception based on the notion of temporal qualities, which are mental properties that are instantiated whenever we detect change in the environment. When we become aware of these temporal qualities in an appropriate way, our conscious experience will feature the distinct temporal phenomenology that is associated with (...) the passing of time. The temporal qualities model of perception makes two predictions about the mechanisms of time perception; one that time perception is modality specific and the other that it can occur without awareness. My argument for this view partially depends on a number of psychophysical experiments that I designed and implemented myself and which investigate subjective time distortions caused by looming visual stimuli. These results show that the mechanisms of conscious experience of time are distinct from the mechanisms of time perception, as my theory of temporal qualities predicts. (shrink)

We explored whether information processed subconsciously in blindsight is qualitatively different from normal conscious processing. On each trial the blindsight patient GY was presented with a square-wave grating either in an upper or lower quadrant of his visual field and was asked to report the opposite of its location . We found that while GY was able to follow these exclusion instructions in his normal field, he tended to erroneously respond with the real location when the grating appeared in his (...) blind field. Remarkably, his error rate actually increased with increasing grating contrast in his blind field. The interpretation of these results does not rely on subjective reports and thus cannot be criticized on the grounds that subjective reports are unreliable. We conclude that blindsight is unlike normal conscious vision. (shrink)

Visual stimuli as well as transcranial magnetic stimulation can be used: to suppress the visibility of a target and to recover the visibility of a target that has been suppressed by another mask. Both types of stimulation thus provide useful methods for studying the microgenesis of object perception. We first review evidence of similarities between the processes by which a TMS mask and a visual mask can either suppress the visibility of targets or recover such suppressed visibility. However, we then (...) also point out a significant difference that has important implications for the study of the time course of unconscious and conscious visual information processing and for theoretical accounts of the processes involved. We present evidence and arguments showing: that visual masking techniques, by revealing more detailed aspects of target masking and target recovery, support a theoretical approach to visual masking and visual perception that must take into account activities in two separate neural channels or processing streams and, as a corollary, that at the current stage of methodological sophistication visual masks, by acting in more highly specifiable ways on these pathways, provide information about the microgenesis of form perception not available with TMS masks. (shrink)

Using a metacontrast masking paradigm, prior studies have shown that a target’s color information and form information, can be processed without awareness and that unconscious color processing occurs at early, wavelength-dependent levels in the cortical information processing hierarchy. Here we used a combination of paracontrast and metacontrast masking techniques to explore unconscious color and form priming effects produced by blue, green, and neutral stimuli. We found that color priming in normal observers is significantly reduced when an additional paracontrast mask precedes (...) the target at optimal masking SOAs. However, no reduction of form-priming effects was obtained at similar optimal paracontrast SOAs. We conclude that unconscious color priming depends on an early, wavelength- or stimulus-dependent response of color neurons located at early cortical levels whereas unconscious form priming occurs at later levels. (shrink)

Masked stimuli can affect the preparation of a motor response to subsequently presented target stimuli. Under some conditions, reactions to the main stimulus can be facilitated or inhibited when preceded by a compatible prime . In the majority of studies in which inverse priming was demonstrated arrows pointing left or right were used as prime and targets. There is, however, evidence that arrows are special overlearned stimuli which are processed in a favorable way. Here we report three experiments designated to (...) test whether the “arrowness” of primes/targets is a sufficient condition for inverse priming. The results clearly show that although inverse priming appeared when non-arrow shapes were used, the magnitude of the priming effect was larger with arrows. The possible reasons for this effect are discussed. (shrink)

While it is known that reward induces attentional prioritization, it is not clear what effect reward-learning has when associated with stimuli that are not fully perceived. The masked priming paradigm has been extensively used to investigate the indirect impact of brief stimuli on response behavior. Interestingly, the effect of masked primes is observed even when participants choose their responses freely. While classical theories assume this process to be automatic, recent studies have provided evidence for attentional modulations of masked priming effects. (...) Most such studies have manipulated bottom-up or top-down modes of attentional selection, but the role of “newer” forms of attentional control such as reward-learning and selection history remains unclear. In two experiments, with number and arrow primes, we examined whether reward-mediated attentional selection modulates masked priming when responses are chosen freely. In both experiments, we observed that primes associated with high-reward lead to enhanced free-choice priming compared to primes associated with no-reward. The effect was seen on both proportion of choices and response times, and was more evident in the faster responses. In the slower responses, the effect was diminished. Our study adds to the growing literature showing the susceptibility of masked priming to factors related to attention and executive control. (shrink)

Are emotion-producing processes modular? Jerry Fodor, in his classic introduction of the notion of modularity, holds that its most important feature is cognitive impenetrability or information encapsulation. If a process possesses this feature, then, as standardly understood, “what we want or believe makes no difference to how [it] works”.In this paper, we will start with the issue of the cognitive impenetrability of emotion-producing processes. It turns out that, while there is abundant evidence of emotion-producing processes that are not cognitively impenetrable, (...) some nonetheless are. We will look at two sorts of case. The first concerns emotional reactions to observed faces, and the second involves what we can call “primitive emotions,” emotions that can be activated by non-doxastic input into regions of the brain we share with more primitive animals.In seeing how some emotion-producing processes can be cognitively impenetrable while others are not, we need to use two commonsensical theses. First, a discussion of modularity must in general operate with a taxonomy that allows for sub-processes or stages of processes. (shrink)

Strawson’s challenging and provocative defence of panpsychism1 begins by sensibly insisting that physicalism, properly understood, must unflinchingly countenance the occurrence of conscious experiences. No view, he urges, will count as ‘real physicalism’ (p. 4) if it seeks to get around or soften that commitment, as versions of socalled physicalism sometimes do. Real physicalism (hereinafter physicalism tout court) must accordingly reject any stark opposition of mental and physical, which is not only invoked by many followers of Descartes, but even countenanced by (...) many recent physicalists. Conscious experiences, Strawson persuasively urges, are a special case of the physical, just as cows are animals. Panpsychism enters the picture because, despite the physical nature of conscious experiences, Strawson maintains that we cannot describe or explain the experiential using the terms of physics or neurophysiology. Since the experiential is nonetheless physical, Strawson concludes that the physical ultimates must, in addition to whatever properties physics and neurophysiology reveal, have experiential properties as well. Strawson argues that we cannot avoid this conclusion by maintaining that combinations of physical ultimates constitute or give rise to experiential properties. Physical ultimates cannot give rise to conscious experience unless those ultimates are themselves in some way ‘intrinsically experiential’ (p. 22). The experiential cannot emerge from nonexperiential ultimates in the way that macroscopic liquidity is standardly held to emerge from molecular properties. Strawson concludes that at least some physical ultimates must be ‘intrinsically experience-involving’ (p. 22); and, since it’s reasonable to see the physical ultimates as homogeneous in nature, we should assume that they all have experiential properties. (shrink)

Our visual systems account for stimulus context in brightness perception, but whether such adjustments occur for stimuli that we are unaware of has not been established. We therefore assessed whether stimulus context influences brightness processing by measuring unconscious priming with metacontrast masking. When a middle-gray disk was presented on a darker background, such that it could be consciously perceived as brighter via simultaneous brightness contrast , reaction times were significantly faster to a bright annulus than to a dark annulus. We (...) further show that context-dependent brightness priming does not correlate with visibility using an objective measure of awareness and that context-dependent, but not context-independent brightness priming, occurs equally strongly for stimuli below or above the subjective threshold for awareness . These results suggest that SBC occurs at early levels of visual input and is not influenced by conscious perception. (shrink)

Shapes that are rendered invisible through backward masking are still able to influence motor responses: this is called masked priming. Yet it is unknown whether this influence is on the control of ongoing action, or whether it merely influences the initiation of an already-programmed action. We modified a masked priming procedure such that the critical prime-mask sequence was displayed during the execution of an already-initiated goal-directed pointing movement. Psychophysical tests of prime visibility indicated that the identity of the prime shapes (...) were not accessible to participants for conscious report. Yet detailed kinematic analysis of the finger in motion revealed that masked primes had an influence on the pointing trajectories within 277 ms of their appearance, 56 ms earlier than the trajectory deviations observed in response to the visible masks. These results indicate that subliminal shapes can indeed influence the control of ongoing motor activity. (shrink)

Recently, a new movement has arisen in the philosophy of perception: one that views perception as a natural kind. Strangely, this movement has neglected the extensive work in philosophy of science on natural kinds. The present paper remedies this. I start by isolating a widespread and influential assumption, which is that we can give necessary and sufficient conditions for perception. I show that this assumption is radically at odds with current philosophy of science work on natural kinds. I then develop (...) an alternative, new view of perception. This new view takes as its starting point the dominant position on kinds in the life sciences: the homeostatic property cluster account. I show that, if you accept this view, then all of the putative cases of unconscious perception are more plausibly seen as cases where it is indeterminate whether the mental episode in question is an instance of perception. (shrink)

We examined the updating of decisions made during visuo-motor processing when two sequentially presented stimuli, Prime1 and Prime2, primed discriminative responses to a following probe. In Experiment 1, the visibility of the two primes was suppressed or left intact by varying the stimulus onset asynchrony of the stimuli immediately following them. In Experiment 2, the visibility of Prime2 was suppressed or left intact by varying its spatial separation from the following probe. We found that Prime2 dominated the effects of Prime1; (...) that Prime2’s updating was stronger when the Prime2–probe SOA was 200 as compared to 53 ms; and that Prime2’s updating was weaker when the Prime2–probe spatial separation was 58 as compared to 0 minarc. We conclude that these effects are due to an interaction of spatial attention and the state of processing of Prime2. (shrink)