There is currently no consensus regarding what measures are most valid to demonstrate perceptual processing without awareness. Likewise, whether conscious perception and unconscious processing rely on independent mechanisms or lie on a continuum remains a matter of debate. Here, we addressed these issues by comparing the time courses of subjective reports, objective discrimination performance and response priming during meta-contrast masking, under similar attentional demands. We found these to be strikingly similar, suggesting that conscious perception and unconscious processing cannot be dissociated (...) by their time course. Our results also demonstrate that unconscious processing, indexed by response priming, occurs, and that objective discrimination performance indexes the same conscious processes as subjective visibility reports. Finally, our results underscore the role of attention by showing that how much attention the stimulus receives relative to the mask, rather than whether processing is measured by conscious discrimination or by priming, determines the time course of meta-contrast masking. (shrink)

Research has shown repeatedly that attention influences implicit learning effects. In a similar vein, interoceptive awareness might be involved in unaware fear conditioning: The fact that the CS is repeatedly presented in the context of aversive bodily experiences might facilitate the development of conditioned responding. We investigated the role of interoceptive attention in a subliminal conditioning paradigm. Conditioning was embedded in a spatial cueing task with subliminally presented cues that were followed by a masking stimulus. Response times to the targets (...) that were either validly or invalidly predicted by the cues served as index of conditioning. Interoceptive attention was manipulated between-subjects. Half the participants completed a heartbeat detection task before conditioning. This task tunes attention to one’s own bodily signals. We found that conditioned responding was facilitated in this latter group of participants. These results are in line with the hypothesis that a rise interoceptive attention enhances unaware conditioned responding. (shrink)

When is choice affected by subliminal messages? This question has fascinated scientists and lay people alike, but it is only recently that reliable empirical data began to emerge. In the current paper we bridge the literature on implicit motivation and that on subliminal persuasion. We suggest that motivation in general, and implicit motivation more specifically, plays an important role in subliminal persuasion: It sensitizes us to subliminal cues. To examine this hypothesis we developed a new paradigm that allows powerful tests (...) of subliminal influences as well as stringent assessments of subliminality. The results of two experiments suggest that implicit motivation can enhance the effects of subliminal priming on choice. (shrink)

We propose a new masking technique for masking word stimuli. Drawing on the phenomena of metacontrast and paracontrast, we alternately presented two prime displays of the same word with the background color in one display matching the font color in the other display and vice versa. The sequence of twenty alterations was sandwich-masked by structure masks. Using this masking technique, we conducted evaluative priming experiments with positive and negative target and prime words. Significant priming effects were found – for primes (...) and targets drawn from the same as well as from different word sets. Priming effects were independent of prime discrimination performance in direct tests and they were still significant after the sample was restricted to those participants who showed random responding in the direct test. (shrink)

Regarding awareness as a consistent concept has contributed to the controversy about implicit learning. The present study emphasized the importance of distinguishing aspects of awareness in order to determine whether learning is implicit. By decomposing awareness into awareness of contingencies, of the procedure being a learning task, and of the reinforcing stimuli, it was demonstrated that implicit operant learning modulated pain sensitivity. All of these aspects of awareness were demonstrated to not be necessary for learning. Additionally, discrimination of contingencies was (...) not necessary on different levels of processing as demonstrated by a verbal and a behavioral method. It was demonstrated that explicit cognitive processes about one’s own behavior, impaired learning, even though these cognitions were not immediately related to the learning process. The results of this study are of special interest in the context of pain, since implicit operant learning can explain the gradual development of hypersensitivity in chronic pain. (shrink)

Visual stimuli that are made invisible by a following mask can nonetheless affect motor responses. To localize the origin of these target priming effects we used the psychological refractory period paradigm. Participants classified tones as high or low, and responded to the position of a visual target that was preceded by a prime. The stimulus onset asynchrony between both tasks varied. In Experiment 1 the tone task was followed by the position task and SOA dependent target priming effects were observed. (...) When the visual position task preceded the tone task in Experiment 2, with short SOA the priming effect propagated entirely to the tone task yielding faster responses to tones on visually congruent trials and delayed responses to tones on visually incongruent trials. Together, results suggest that target priming effects arise from processing before and at the level of the central bottleneck such as sensory analysis and response selection. (shrink)

Subjects classified visible 2-digit numbers as larger or smaller than 55. Target numbers were preceded by masked 2-digit primes that were either congruent (same relation to 55) or incongruent. Experiments 1 and 2 showed prime congruency effects for stimuli never included in the set of classified visible targets, indicating subliminal priming based on long-term semantic memory. Experiments 2 and 3 went further to demonstrate paradoxical unconscious priming effects resulting from task context. For example, after repeated practice classifying 73 as larger (...) than 55, the novel masked prime 37 paradoxically facilitated the “larger” response. In these experiments task context could induce subjects to unconsciously process only the leftmost masked prime digit, only the rightmost digit, or both independently. Across 3 experiments, subliminal priming was governed by both task context and long-term semantic memory. (shrink)

Note posted 9 Jun 08 : Modifications made today include a new section on predictive validity, and addition of recently published article and in in-press article, both by Nosek & Hansen, under the "CULTURE VS. PERSON" heading, which replaces a previously listed unpublished ms. of theirs. I continue to encourage all interested to send material that they are willing to be included on this page. Please also to let me know about errors, including faulty links.

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)

This article reports four subliminal perception experiments using the relationship between confidence and accuracy to assess awareness. Subjects discriminated among stimuli and indicated their confidence in each discrimination response. Subjects were classified as being aware of the stimuli if their confidence judgments predicted accuracy and as being unaware if they did not. In the first experiment, confidence predicted accuracy even at stimulus durations so brief that subjects claimed to be performing at chance. This finding indicates that subjects's claims that they (...) are ''just guessing'' should not be accepted as sufficient evidence that they are completely unaware of the stimuli. Experiments 2-4 tested directly for subliminal perception by comparing the minimum exposure duration needed for better than chance discrimination performance against the minimum needed for confidence to predict accuracy. The latter durations were slightly but significantly longer, suggesting that under certain circumstances people can make perceptual discriminations even though the information that was used to make those discriminations is not consciously available. (shrink)

Recent research suggests that processing of irrelevant information can be modulated in a rapid online fashion by contextual information in the task environment depending on the usefulness of that information in different contexts. Congruency effects evoked by irrelevant stimulus attributes are smaller in contexts with high proportions of incongruent trials and larger in contexts with high proportions of congruent trials . The present study investigates these context-adaptation effects in a masked-priming paradigm. Context-specific adaptation effects transfer to stimulus identities that are (...) equiprobale in all contexts – an observation that renders explanations in terms of event-learning processes unlikely. Yet, context-specific effects vanished when the irrelevant information remained unconscious. The results suggest that context-specific adaptation of congruency effects reflect cognitive control operations that alter the processing of irrelevant information depending on the experienced utility of that information for action control. (shrink)

Using an explicit task cuing paradigm, we tested whether masked cues can trigger task-set activation, which would suggest that unconsciously presented stimuli can impact cognitive control processes. Based on a critical assessment of previous findings on the priming of task-set activation, we present two experiments with a new method to approach this subject. Instead of using a prime, we varied the visibility of the cue. These cues either directly signaled particular tasks in Experiment 1, or certain task transitions in Experiment (...) 2. While both masked task and transition cues affected task choice, only task cues affected the speed of task performance. This observation suggests that task-specific stimulus–response rules can be activated only by masked cues that are uniquely associated with a particular task. Taken together, these results demonstrate that unconsciously presented stimuli have the power to activate corresponding task sets. (shrink)

It has been proposed that inferring personal authorship for an event gives rise to intentional binding, a perceptual illusion in which one’s action and inferred effect seem closer in time than they otherwise would . Using a novel, naturalistic paradigm, we conducted two experiments to test this hypothesis and examine the relationship between binding and self-reported authorship. In both experiments, an important authorship indicator – consistency between one’s action and a subsequent event – was manipulated, and its effects on binding (...) and self-reported authorship were measured. Results showed that action-event consistency enhanced both binding and self-reported authorship, supporting the hypothesis that binding arises from an inference of authorship. At the same time, evidence for a dissociation emerged, with consistency having a more robust effect on self-reports than on binding. Taken together, these results suggest that binding and self-reports reveal different aspects of the sense of authorship. (shrink)

Four experiments demonstrate category congruency priming by subliminal prime words that were never seen as targets in a valence-classification task and a gender-classification task . In Experiment 1, overlap in terms of word fragments of one or more letters between primes and targets of different valences was larger than between primes and targets of the same valence. In Experiments 2 and 3, the sets of prime words and target words were completely disjoint in terms of used letters. In Experiment 4, (...) pictures served as targets. The observed subliminal priming effects for novel primes cannot be driven by partial analysis of primes at the word-fragment level; they suggest instead that primes were processed semantically as whole words contingent upon prime duration. (shrink)

Lane, K. A., Banaji, M. R., Nosek, B. A., & Greenwald, A. G. (2007). Understanding and using the Implicit Association Test: IV. What we know (so far) (Pp. 59–102). In B. Wittenbrink & N. S. Schwarz (Eds.). Implicit measures of attitudes: Procedures and controversies . New York: Guilford Press. PDF - 652KB ].

Unconscious processes, by whatever name they may be known , are invariably operationalized by the dissociation paradigm, any situation involving the dissociation between two indicators , one of availability and the other, of accessibility , such that, ε>α. Subliminal perception has been traditionally defined by a special case of the dissociation paradigm in which availability exceeds accessibility when accessibility is null . Construct validity issues bedevil all dissociation paradigms since it is not clear what might constitute appropriate indicators that, moreover, (...) are pure and exhaustive. Semantic and theoretic drifts in the recent literature—e.g., the confusion of different versions of the dissociation paradigm, the equation of conscious–unconscious with direct–indirect tests, and the foisting of the criterion of qualitative differences—have tended to undermine emerging theoretic parsimony. On the other hand, a crucial factor has been left out of theory development: time. Both ε and α can rise and fall over time, often asynchronously, and so dissociations may wax and wane and, even, reverse over time. Some laboratory evidence suggests that accessibility measures , as they approach chance, may actually dip below chance . If so, d′=0 , could be an averaging artifact of positive and negative d′s. Conscious accessibility is not either–or but more or less, and variable over time. (shrink)

Comparisons of indirect measures with direct measures can help elucidate the relationship between nonconscious and conscious perception. We report three experiments on masked word priming in which we observed a negative correlation between prime discriminability and priming , i.e. where priming decreased with increasing prime visibility. While such observations are rare , they may indicate a conflict between conscious and nonconscious processing when primes are shown close to the subjective visibility threshold for the priming-relevant information. For instance, such a conflict (...) could occur between nonconscious processing of a prime’s meaning and conscious perception of prime letters. Theoretical accounts that discuss similar conflicts assume that the conflict is resolved either by automatically prioritising conscious processes or by discounting the estimated confusion caused by a prime-target pair . In both cases, priming is predicted to decrease when prime visibility increases from below threshold to perithreshold levels. Therefore, we suggest that negative priming-d’ relationships are most likely observed when the d’ measure assesses prime visibility at a level of representation that is below the level of representation at which priming arises, in terms of a putative hierarchy of word processing. (shrink)

The Objective Threshold/Strategic Model proposes that strong, qualitative inferences of unconscious perception can be made if the relationship between perceptual sensitivity and stimulus visibility is nonlinear and nonmonotonic. The model proposes a nadir in priming effects at the objective identification threshold . These predictions were tested with masked semantic priming and repetition priming of a lexical decision task. The visibility of the prime stimuli was systematically varied above and below the objective identification threshold. The obtained relationship between prime visibility and (...) priming facilitation was nonlinear, but the results failed to confirm a nadir in priming effects at the objective identification threshold. We conclude that the objective identification threshold does not necessarily indicate the point where presumably unconscious priming effects might be inhibited by conscious cognitive processes. (shrink)

Recent evidence suggests that consciousness of encoding is not necessary for the rapid formation of new semantic associations. We investigated whether unconsciously formed associations are as semantically precise as would be expected for associations formed with consciousness of encoding during episodic memory formation. Pairs of faces and written occupations were presented subliminally for unconscious associative encoding. Five minutes later, the same faces were presented suprathreshold for the cued unconscious retrieval of face-occupation associations. Retrieval instructions required participants to classify the presented (...) individuals according to their putative regularity of income, length of education, and creativity value of occupational activity. The three instructions yielded more classifications consistent with a person’s occupation if the person had been subliminally presented with his written occupation versus a meaningless word . This suggests that consciousness is not necessary to encode, long-term store, and retrieve semantically precise associations between primarily unrelated items. (shrink)

Using the Implicit Association Test, recent experiments have demonstrated a strong and automatic positive evaluation of White Americans and a relatively negative evaluation of African Americans. Interpretations of this finding as revealing pro-White attitudes rest critically on tests of alternative interpretations, the most obvious one being perceivers’ greater familiarity with stimuli representing White Americans. The reported experiment demonstrated that positive attributes were more strongly associated with White than Black Americans even when pictures of equally unfamiliar Black and White individuals were (...) used as stimuli and differences in stimulus familiarity were statistically controlled. This experiment indicates that automatic race associations captured by the IAT are not compromised by stimulus familiarity, which in turn strengthens the conclusion that the IAT measures automatic evaluative associations. © 2000 Academic Press. (shrink)

The aim of this study was to investigate unconscious priming by the use of a spatial mirror-masking paradigm. Words and nonwords with no under-length letters are mirrored at their horizontal axis. The results are figures of geometric-like forms that contain letters in their upper part. In the three experiments reported in this study, a priming procedure used such mirrored words and nonwords as primes. Participants were ignorant of the nature of the construction of the stimuli. Perceptual reports of the participants (...) revealed that they did not realize that words were hidden in the primes. Nevertheless, they showed priming in all three experiments. Priming effects were replicated with prime–target SOAs of between 1 and 3 s. Functional dissociations were found between ignorant and informed participants. Informed groups showed perceptual and semantic priming, while ignorant groups showed only perceptual priming. (shrink)

The present ERP study investigated effects of subliminal emotional words on preference judgments about subsequent visual target stimuli . Each target was preceded by a masked 17-ms emotional adjective. Four classes of prime words were distinguished according to the combinations of positive/negative valence and high/low arousal. Targets were liked significantly more after positive-arousing primes , relative to negative-arousing , positive-nonarousing , and negative-nonarousing primes . In the target ERP, amplitude of right-hemisphere positive slow wave was increased after positive-arousing compared to (...) negative-arousing primes. Evaluative priming effects on judgments and ERPs were more pronounced in high state-anxious participants. The results suggest that there is indeed affective/semantic processing of unconscious words, evaluative priming operates relatively late during target processing, to be effective, prime words need to score high on the arousal dimension, and individual differences in state anxiety modulate the susceptibility to subliminal evaluative priming. (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)

Recently, priming effects of unconscious stimuli that were never presented as targets have been taken as evidence for the processing of the stimuli’s semantic categories. The present study explored the necessary conditions for a transfer of priming to novel primes. Stimuli were digits and letters which were presented in various viewer-related orientations . The transfer of priming to novel stimulus orientations and identities was remarkably limited: in Experiment 1, in which all conscious targets stood upright, no transfer to unconscious primes (...) in a non-target orientation was found. Experiment 2, in which primes were presented without masks, ruled out the possibility that primes were presented too short to allow congruency effects. In Experiments 3 and 4, in which all targets were presented upside down, priming transferred to upright stimuli with target identities but neither to horizontal stimuli nor to stimuli with novel identities. We suggest that whether a transfer of priming to unpracticed stimuli occurs or not depends on observers’ expectations of specific stimulus exemplars. (shrink)

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)

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)

In masked priming tasks responses are usually faster when prime and target require identical rather than different responses. Previous research has extensively manipulated the nature and number of response-affording stimuli. However, little is known about the constraints of masked priming regarding the nature and number of response alternatives. The present study explored the limits of masked priming in a six-choice reaction time task, where responses from different fingers of both hands were required. We studied participants that were either experts for (...) the type of response or novices. Masked primes facilitated responding to targets that required the same response, responses with a different finger of the same hand, and with a homologous finger of the other hand. These effects were modulated by expertise. The results show that masked primes facilitate responding especially for experts in the S–R mapping and with increasing similarity of primed and required response. (shrink)

In his analysis of subliminal perception research, Erdelyi documented two important phenomena: subchance perception and temporal variability in stimulus availability and accessibility. This Commentary addresses three issues raised by Erdelyi's review: the importance of distinguishing “micro” from “macro” temporal shifts; the need to analyze perception without awareness data at the level of the individual as well as the group; and parallels between the dissociations associated with neuroclinical phenomena and those observed in patients with certain forms of personality pathology. Continued integration (...) of laboratory findings with in vivo observations of clinical syndromes will yield a more cohesive and heuristic approach to the study of implicit mental states. (shrink)