When consciousness is examined using subjective ratings, the extent to which processing is conscious or unconscious is often estimated by calculating task performance at the subjective threshold or by calculating the correlation between accuracy and awareness. However, both these methods have certain limitations. In the present article, we propose describing task accuracy and awareness as functions of stimulus intensity as suggested by Koch and Preuschoff . The estimated lag between the curves describes how much stimulus intensity must increase for awareness (...) to change proportionally as much as accuracy and the slopes of the curves are used to assess how fast accuracy and awareness increases and whether awareness is dichotomous. The method is successfully employed to assess consciousness characteristics on data from four different awareness scales. (shrink)

Conscious visual perception can fail in many circumstances. However, little is known about the causes and processes leading to failures of visual awareness. In this study, we introduce a new signal detection measure termed subjective discriminability of invisibility that allows one to distinguish between subjective blindness due to reduction of sensory signals or to lack of attentional access to sensory signals. The SDI is computed based upon subjective confidence in reporting the absence of a target . Using this new measure, (...) we found that target misses were subjectively indistinguishable from physical absence when contrast reduction, backward masking and flash suppression were used, whereas confidence was appropriately modulated when dual task, attentional blink and spatial uncertainty methods were employed. These results show that failure of visual perception can be identified as either a result of perceptual or attentional blindness depending on the circumstances under which visual awareness was impaired. (shrink)

A series of experiments tested the hypothesis that very brief exposure to feared stimuli can have positive effects on avoidance of the corresponding feared object. Participants identified themselves as fearful of spiders through a widely used questionnaire. A preliminary experiment showed that they were unable to identify the stimuli used in the main experiments. Experiment 2 compared the effects of exposure to masked feared stimuli at short and long stimulus onset asynchronies . Participants were individually administered one of three continuous (...) series of backwards masked or non-masked stimuli: unreportable images of spiders , clearly visible images of spiders , or unreportable images of trees . Immediately thereafter, they engaged in a Behavioral Avoidance Test with a live, caged tarantula. Exposure to unreportable images of spiders resulted in greater approach towards the tarantula than unreportable neutral images. A post-hoc comparison with clearly visible exposure to these same images approached significance. These effects were maintained at a 1-week follow-up . In Experiment 3 , participants engaged in the BAT 1 week prior to the exposure manipulation in order to provide a baseline measurement of their avoidant behavior, and again immediately after the exposure manipulation. Exposure to unreportable images of spiders reduced avoidance of the tarantula. Similar exposure to trees did not. Implications for the non-conscious basis of fear are discussed. (shrink)

“Source monitoring” theory is applied to the turn-of-the-century argument that, whenever binocularly fused patterns are self-consciously apperceived, both eyes' monocular sensations are consciously perceived. According to monitoring theory's refinement of the argument, binocularly apperceived patterns are accompanied by selfconsciousness that one is perceiving patterns , whereas monocular sensations are accompanied by no self-consciousness of their source. In the current test of this refined argument, 32 subjects were monocularly presented with 6 letters of the alphabet, while binocularly fusing 6 different letters, (...) and were subsequently required to discriminate these 12 letters from 6 other letters that they had visually imaged. Consistent with monitoring theory, the results of experimental testing suggest that binocularly fused letters are neurally monitored as “peripheral,” self-consciously experienced as “perceived,” and subsequently remembered as not “imaged.” The results further suggest that, during such binocular apperception, monocular data are not totally unconscious-like computer data-but are consciously experienced as “sourceless” sensations that are memorially confused with visually imaged sensations. (shrink)

This paper considers different subjective measures of conscious and unconscious knowledge in a concept formation paradigm. In particular, free verbal reports are compared with two subjective measures, the zero-correlation and the guessing criteria, based on trial-by-trial confidence ratings (a type of on-line verbal report). Despite the fact that free verbal reports are frequently dismissed as being insensitive measures of conscious knowledge, a considerable bulk of research on implicit learning has traditionally relied on this measure of consciousness, because it is widely (...) regarded as almost self-evident that the content of any conscious state that is intentional and conceptual can be expressed verbally. However, we found that the most recently developed subjective measures based on trial-by-trial confidence ratings provided a more sensitive measure of conscious and unconscious knowledge than free verbal reports. In a complementary way, the qualitative pattern of the free report and the confidence measures were similar, providing further evidence for the validity of the latter. (shrink)

Executive control of attention refers to processes that detect and resolve conflict among competing thoughts and actions. Despite the high-level nature of this faculty, the role of awareness in executive control of attention is not well understood. In this study, we used interocular suppression to mask the flankers in an arrow flanker task, in which the flankers and the target arrow were presented simultaneously in order to elicit executive control of attention. Participants were unable to detect the flanker arrows or (...) to reliably identify their direction when masked. There was a typical conflict effect (prolonged reaction time and increased error rate under flanker-target incongruent condition compared to congruent condition) when the flanker arrows were unmasked, while the conflict effect was absent when the flanker arrows were masked with interocular suppression. These results suggest that blocking awareness of competing stimuli with interocular suppression prevents the involvement of executive control of attention. (shrink)

The relations between automatic processing and consciousness are discussed in this paper. It is argued that automatic processing should not be identified with the absence of consciousness. The organism has access to representations resulting from automatic processing, but these representations, in contrast to the representations resulting from nonautomatic processing, are not propositional. Therefore monitoring of the process, the defining feature of nonautomatic processing, is not possible.

Here, we explore the sensitivity of different awareness scales in revealing conscious reports on visual emotion perception. Participants were exposed to a backward masking task involving fearful faces and asked to rate their conscious awareness in perceiving emotion in facial expression using three different subjective measures: confidence ratings , with the conventional taxonomy of certainty, the perceptual awareness scale , through which participants categorize “raw” visual experience, and post-decision wagering , which involves economic categorization. Our results show that the CR (...) measure was the most exhaustive and the most graded. In contrast, the PAS and PDW measures suggested instead that consciousness of emotional stimuli is dichotomous. Possible explanations of the inconsistency were discussed. Finally, our results also indicate that PDW biases awareness ratings by enhancing first-order accuracy of emotion perception. This effect was possibly a result of higher motivation induced by monetary incentives. (shrink)

Previous research has shown that people can implicitly acquire mappings between word forms and literal meanings . We argue, from the metaphor-representation and embodiment perspectives, that people can unconsciously establish mappings between word forms and not only literal but also metaphorical meanings. Using Williams’ paradigm, we found that transfer of form-meaning connections from a concrete domain to an abstract domain was achieved in a metaphor-consistent way without awareness. Our results support the view that unconscious knowledge can be flexibly deployed in (...) an abstract way not previously explored in the implicit learning literature. (shrink)

Erdelyi does us all a great service by his customarily incisive discussion of the various ways in which our field tends to neglect, confuse, and misunderstand numerous critical issues in attempting to differentiate conscious from unconscious perception and memory. Although no single commentary could hope to comprehensively assess these issues, I will address Erdelyi’s three main points: How the dissociation paradigm can be used to validly infer unconscious perception; The implications of below-chance effects; and The role of time. I suggest (...) that significant progress on construct validity issues is possible; below-chance effects are part of a more general bidirectional phenomenon, very likely unconscious, and do not threaten absolute subliminality; and practice/learning effects pose potential difficulties for time-based dissociation paradigms. (shrink)

Participants struck 500 golf balls to a concealed target. Outcome feedback was presented at the subjective or objective threshold of awareness of each participant or at a supraliminal threshold. Participants who received fully perceptible feedback learned to strike the ball onto the target, as did participants who received feedback that was only marginally perceptible . Participants who received feedback that was not perceptible showed no learning. Upon transfer to a condition in which the target was unconcealed, performance increased in both (...) the subjective and the objective threshold condition, but decreased in the supraliminal condition. In all three conditions, participants reported minimal declarative knowledge of their movements, suggesting that deliberate hypothesis testing about how best to move in order to perform the motor task successfully was disrupted by the impoverished disposition of the visual outcome feedback. It was concluded that sub-optimally perceptible visual feedback evokes implicit processes. (shrink)

Reingold and MerikleÕs (1988, 1990) critique of the classic dissociation paradigm identified several issues as inherent problems that severely undermine the utility of this paradigm. Erdelyi (2004) extending his prior analysis (Erdelyi, 1985, 1986) points out several additional factors that may complicate the interpretation of empirically obtained dissociations. The goal of the present manuscript is to further discuss some of these commonly neglected interpretive difficulties. Ó 2003 Elsevier Inc. All rights reserved.

Events often share elements that guide us to integrate knowledge from these events. Integration allows us to make inferences that affect reactions to new events. Integrating events and making inferences are thought to depend on consciousness. We show that even unconsciously experienced events, that share elements, are integrated and influence reactions to new events. An unconscious event consisted of the subliminal presentation of two unrelated words. Half of subliminal word pairs shared one word . Overlapping word pairs were presented between (...) 6 s and 78 s apart. The test for integration required participants to judge the semantic distance between suprathreshold words . Evidence of integration was provided by faster reactions to suprathreshold words that were indirectly related versus unrelated. This effect was independent of the time interval between overlapping word pairs. We conclude that consciousness is no requirement for the integration of discontiguous events. (shrink)

Evaluative learning refers to the change in the affective evaluation of a previously neutral stimulus that occurs after the stimulus has been associated with a second, positive or negative, affective stimulus . Four experiments are reported in which the AS was presented very briefly. Significant evaluative learning was observed in participants who did not notice the presentation of the affective stimuli or could not discriminate between the briefly presented positive and negative ASi when asked to do so . In two (...) other experiments , no significant learning effect was obtained. A meta-analysis performed on the present and previously reported results gave evidence for a small, though statistically reliable evaluative learning effect when ASi are presented “subliminally.” This finding supports the hypothesis that evaluative associations can be learned implicitly. (shrink)

We first describe how the concept of “fringe consciousness” can characterise gradations of consciousness between the extremes of implicit and explicit learning. We then show that the NEO-PI-R personality measure of openness to feelings, chosen to reflect the ability to introspect on fringe feelings, influences both learning and awareness in the serial reaction time task under conditions that have previously been associated with implicit learning . This provides empirical evidence for the proposed phenomenology and functional role of fringe consciousness in (...) so-called implicit learning paradigms . Introducing an individual difference variable also helped to identify possible limitations of the exclusion task as a measure of conscious sequence knowledge. Further exploration of individual differences in fringe awareness may help to avoid polarity in the implicit learning debate, and to resolve apparent inconsistencies between previous SRT studies. (shrink)

There is growing interest in the effect of sound on visual motion perception. One model involves the illusion created when two identical objects moving towards each other on a two-dimensional visual display can be seen to either bounce off or stream through each other. Previous studies show that the large bias normally seen toward the streaming percept can be modulated by the presentation of an auditory event at the moment of coincidence. However, no reports to date provide sufficient evidence to (...) indicate whether the sound bounce-inducing effect is due to a perceptual binding process or merely to an explicit inference resulting from the transient auditory stimulus resembling a physical collision of two objects. In the present study, we used a novel experimental design in which a subliminal sound was presented either 150 ms before, at, or 150 ms after the moment of coincidence of two disks moving towards each other. The results showed that there was an increased perception of bouncing when the subliminal sound was presented at or 150 ms after the moment of coincidence compared to when no sound was presented. These findings provide the first empirical demonstration that activation of the human auditory system without reaching consciousness affects the perception of an ambiguous visual motion display. (shrink)