According to the concept of direct parameter specification, nonconsciously registered information can be processed to the extent that it matches currently active intentions of a person. This prediction was tested and confirmed in the current study. Masked visual information provided by peripheral cues led to reaction time effects only if the information specified one of the required responses . Information delivered by the same masked cues that did not match the intentions was not used. However, the same information influenced RT (...) if it was provided by visible cues . The results suggest that the processing of nonconsciously registered information is flexible because it is susceptible to the changing intentions of a person. Yet, these processes are apparently restricted, as nonconsciously registered information cannot be used as easily for purposes not corresponding to the currently active intentions as better visible information. (shrink)

In a recent paper in Psychological Science, Kouider and Dupoux reported obtaining unconscious Stroop priming only when subjects had partial awareness of the masked distractor words . Kouider and Dupoux conjectured that semantic priming occurs only when such partial awareness is present. The present experiments tested this conjecture in an affective categorization priming task that differed from Kouider and Dupoux’s in using masked distractors that subjects had practiced earlier as visible words. Experiment 1 showed priming from practiced words when subjects (...) had no partial awareness of those words. Experiment 2 showed that, in the absence of partial awareness, practiced words yielded priming but not-practiced words did not. Experiment 3 corroborated Experiment 1 and 2s results using a different test of partial awareness. These results suggest that unconscious processing of subword elements drives masked semantic priming by practiced words. (shrink)

Visual targets which follow a prime stimulus and a mask can be identified faster when they are incompatible rather than compatible with the prime . According to the self-inhibition hypothesis, the initial activation of the motor response is elicited by the prime based on its identity. This activation leads to benefits for compatible trials and costs for incompatible trials. This motor activation is followed by an inhibition phase, leading to an NCE if perceptual evidence of the prime is immediately removed (...) by the mask. The object-updating and mask-triggered inhibition hypotheses emphasize the role of the mask content . We show that the NCE may appear even if nonmasking neutral flankers are presented instead of a mask. Moreover, although with target-like flankers the NCE is larger, it occurred if flankers and targets are built from dissimilar elements. Therefore, masks/flankers can evoke an inhibition phase independently of whether or not they remove evidence for the prime and whether they are similar to the targets. (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)

We used a qualitative dissociation procedure to assess semantic priming from spatially attended and unattended masked words. Participants categorized target words that were preceded by parafoveal prime words belonging to either the same or the opposite category as the target. Using this paradigm, only non-strategic use of the prime would result in facilitation of the target responses in related trials. Primes were immediately masked or masked with a delay, while spatial attention was allocated to the primes’ location or away from (...) the primes’ location. Immediate masked, strongly related primes facilitated target responses irrespective of the spatial attention. Delayed masked, related primes led to reversed or facilitatory priming depending on whether they were cued or uncued. These findings demonstrate that perceiving a stimulus with or without awareness depends on both stimulus quality and attention orienting and that non-strategic priming can be observed from clear visible but spatially unattended words. (shrink)

Previous studies making use of indirect processing measures have shown that perceptual grouping can occur outside the focus of attention. However, no previous study has examined the possibility of subliminal processing of perceptual grouping. The present work steps forward in the study of perceptual organization, reporting direct evidence of subliminal processing of Gestalt patterns. In two masked priming experiments, Gestalt patterns grouped by proximity or similarity that induced either a horizontal or vertical global orientation of the stimuli were presented as (...) masked primes and followed by visible targets that could be congruent or incongruent with the orientation of the primes. The results showed a reliable priming effect in the complete absence of prime awareness for both proximity and similarity grouping principles. These findings suggest that a phenomenal report of the Gestalt pattern is not mandatory to observe an effect on the response based on the global properties of Gestalt stimuli. (shrink)

Dehaene et al. (2003) showed an absence of conscious, but not masked, conflict effects when patients with schizophrenia performed a number-categorisation priming task. We aimed to replicate these influential results using a different word-categorisation priming task. Counter to Dehaene et al.'s findings, 21 patients and 20 healthy controls showed similar congruence effects for both masked and visible primes. Within patients, a reduced congruence effect for visible primes associated with longer duration of illness and more severe behavioural disorganisation. Patients, unlike controls, (...) were no slower to respond to targets that followed visible compared to masked primes. Conscious conflict effects on priming tasks are not universally reduced in schizophrenia but may associate with chronicity and behavioural disorganisation. That patients were no slower when the preceding primes were clearly visible accords with evidence elsewhere that information processing in schizophrenia is driven more by immediate conscious experience and constrained less by prior events. (shrink)

Two experiments investigated subliminal semantic and form priming in a word-completion task. Visual gap-words with a dominant and a subordinate solution were preceded by form-related or by semantically related words, which were briefly presented and sandwich-masked. Priming of the subordinate solution was assessed in Experiment 1, relative to a neutral condition. Both solutions were primed in Experiment 2. In the absence of conscious prime recognition, both semantic and form primes reliably increased the probability with which the primed solution was given. (...) With our variant of fragment-completion, response priming can be ruled out as explanation. Moreover, effects were already present at first presentation, excluding an interpretation in terms of partial awareness due to massive repetition. The data demonstrate automatic activation at both form and semantic levels in the absence of conscious awareness. (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)

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)

Previous research has shown that subliminally presented stimuli accelerate or delay responses afforded by supraliminally presented stimuli. Our experiments extend these findings by showing that unconscious stimuli even affect free choices between responses. Thus, actions that are phenomenally experienced as freely chosen are influenced without the actor becoming aware of the manipulation. However, the unconscious influence is limited to a response bias, as participants chose the primed response only in up to 60% of the trials. LRP data in free choice (...) trials indicate that the prime was not ineffective in trials in which participants chose the non-primed response as then it delayed performance of the incongruently primed response. (shrink)

Visual masking of primes lowers prime visibility but spares processing of primes as reflected in prime–target congruence and prime–response compatibility effects. However, the question is how to appropriately measure prime visibility. Here, we tested the influence of three procedural variables on prime visibility measures: prime–target similarity, prime–response similarity, and the variability of prime–response mappings. Our results show that a low prime–target similarity is a favorable condition for a prime visibility measure because it increases the sensitivity of this measure in comparison (...) to a high prime–target similarity. (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)

In this event-related potential study a masking technique that prevents conscious perception of words and non-words through attentional distraction was used to reveal the temporal dynamics of word processing under non-conscious and conscious conditions. In the non-conscious condition, ERP responses differed between masked words and non-words from 112 to 160 ms after stimulus-onset over posterior brain areas. The early onset of the word–non-word differences was compatible with previous studies that reported non-conscious access to orthographic information within this time period. Moreover, (...) source localisations provided evidence for automatic activation of prelexical phonological information, whereas no evidence for non-conscious semantic processing was found. When subjects were informed about the masking technique, lexical differences occurred at later time intervals, suggesting conscious access to additional word related information. These results indicate that early visual word processing does not depend entirely on attentional resources, but that non-conscious processing probably is restricted to rather lower-level linguistic information. (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)

The present study used masked repetition priming to examine whether face representations can be accessed without attention. Two experiments using a face recognition task presented masked repetition and control primes in spatially unattended locations prior to target onset. Experiment 1 used the same images as primes and as targets and Experiment 2 used different images of the same individual as primes and targets. Repetition priming was observed across both experiments regardless of whether spatial attention was cued to the location of (...) the prime. Priming occurred for both famous and non-famous targets in Experiment 1 but was only reliable for famous targets in Experiment 2, suggesting that priming in Experiment 1 indexed access to view-specific representations whereas priming in Experiment 2 indexed access to view-invariant, abstract representations. Overall, the results indicate that subliminal access to abstract face representations does not rely on attention. (shrink)

6 and 14 recently proposed taxonomies that distinguish between four processing states, based on bottom-up stimulus strength and top-down attentional amplification. The aim of the present study was to empirically test these processing states using the priming paradigm. Our results showed that attention and stimulus strength significantly modulated priming effects: either receiving top-down attention or possessing sufficient bottom-up strength was a prerequisite for a stimulus to elicit priming. When both top-down attention and sufficient bottom-up strength were present, the priming effect (...) was boosted. The origins of the observed priming effects also varied between different processing states. We can conclude that our empirical study using the priming paradigm confirmed the presence of four processing states, which displayed a differential pattern of response priming effects and differential origins of the response priming effects. (shrink)

6 and 14 recently proposed taxonomies that distinguish between four processing states, based on bottom-up stimulus strength and top-down attentional amplification. The aim of the present study was to empirically test these processing states using the priming paradigm. Our results showed that attention and stimulus strength significantly modulated priming effects: either receiving top-down attention or possessing sufficient bottom-up strength was a prerequisite for a stimulus to elicit priming. When both top-down attention and sufficient bottom-up strength were present, the priming effect (...) was boosted. The origins of the observed priming effects also varied between different processing states. We can conclude that our empirical study using the priming paradigm confirmed the presence of four processing states, which displayed a differential pattern of response priming effects and differential origins of the response priming effects. (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)

In agreement with some of the ideas expressed by Perruchet & Vinter (P&V), we believe that some phenomena hitherto attributed to processing may in fact reflect a fundamental distinction between direct and reflexive forms of consciousness. This dichotomy, developed by the phenomenological tradition, is substantiated by examples coming from experimental psychology and lesion neuropsychology.

A series of five experiments investigated the extent of subliminal processing of negation. Participants were presented with a subliminal instruction to either pick or not pick an accompanying noun, followed by a choice of two nouns. By employing subjective measures to determine individual thresholds of subliminal priming, the results of these studies indicated that participants were able to identify the correct noun of the pair – even when the correct noun was specified by negation. Furthermore, using a grey-scale contrast method (...) of masking, Experiment 5 confirmed that these priming effects were evidenced in the absence of partial awareness, and without the effect being attributed to the retrieval of stimulus–response links established during conscious rehearsal. (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)

Masked priming experiments occasionally revealed surprising effects: Participants responded slower for congruent compared to incongruent primes. This negative congruency effect was ascribed to inhibition of prime-induced activation [Eimer, M., & Schlaghecken, F. . Response faciliation and inhibition in subliminal priming. Biological Psychology, 64, 7–26.] that sets in if the prime activation is sufficiently strong. The current study tests this assumption by implementing manipulations designed to vary the amount of prime-induced activation in three experiments. In Experiments 1 and 3, NCEs were (...) observed despite reduced prime-induced activation. Experiment 2 revealed no NCE with at least similar prime strength. Thus, the amount of prime activation did not predict whether or not NCEs occurred. The findings are discussed with regard to the inhibition account and the recently proposed account of mask-induced activation [cf. Lleras, A., & Enns, J. T. . Negative compatibility or object updating? A cautionary tale of mask-dependent priming. Journal of Experimental Psychology: General, 133, 475–493; Verleger, R., Jaskowski, P., Aydemir, A., van der Lubbe, R. H. J., & Groen, M. . Qualitative differences between conscious and nonconscious processing? On inverse priming induced by masked arrows. Journal of Experimental Psychology: General, 133, 494–515]. (shrink)

The claim that visually masked, unidentifiable words are analyzed at the level of whole word meaning has been challenged by recent findings indicating that instead, analysis occurs mainly at the subword level. The present experiments examined possible limits on subword analysis. Experiment 1 obtained semantic priming from pleasant- and unpleasant-meaning subliminal words in which no individual letter contained diagnostic information about a word’s evaluative valence; thus analysis must operate on information more complex than that contained in individual letters. Experiments 2 (...) and 3 showed that analysis must operate on information more complex than that represented by individual bigrams or trigrams . These findings suggest that while subliminal priming is driven by subword analysis, the effective units of analysis are distributed widely across at least short words. (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)