Dynamic adaptation to history of trial difficulty explains the effect of congruency proportion on masked priming.

In reaction time research, there has been an increasing appreciation that response-initiation processes are sensitive to recent experience and, in particular, the difficulty of previous trials. From this perspective, the authors propose an explanation for a perplexing property of masked priming: Although primes are not consciously identified, facilitation of target processing by a related prime is magnified in a block containing a high proportion of related primes and a low proportion of unrelated primes relative to a block containing the opposite mix (Bodner & Masson, 2001). In the present study, this phenomenon is explored with a parity (even/odd) decision task in which a prime (e.g., 2) precedes a target that can be either congruent (e.g., 4) or incongruent (e.g., 3). It is shown that the effect of congruence proportion with masked primes cannot be explained in terms of the blockwise prime–target contingency. Specifically, with masked primes, there is no congruency disadvantage in a block containing a high proportion of incongruent primes, but there is a congruency advantage when the block contains an equal proportion of congruent and incongruent primes. In qualitative contrast, visible primes are sensitive to the blockwise prime–target contingency. The authors explain the relatedness proportion effect found with masked primes in terms of a model according to which response-initiation processes adapt to the statistical structure of the environment, specifically the difficulty of recent trials. This account is supported with an analysis at the level of individual trials using the linear mixed effects model. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Processing of unattended emotional visual scenes.

Prime pictures of emotional scenes appeared in parafoveal vision, followed by probe pictures either congruent or incongruent in affective valence. Participants responded whether the probe was pleasant or unpleasant (or whether it portrayed people or animals). Shorter latencies for congruent than for incongruent prime-probe pairs revealed affective priming. This occurred even when visual attention was focused on a concurrent verbal task and when foveal gaze-contingent masking prevented overt attention to the primes but only if these had been preexposed and appeared in the left visual field. The preexposure and laterality patterns were different for affective priming and semantic category priming. Affective priming was independent of the nature of the task (i.e., affective or category judgment), whereas semantic priming was not. The authors conclude that affective processing occurs without overt attention--although it is dependent on resources available for covert attention--and that prior experience of the stimulus is required and right-hemisphere dominance is involved. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Mechanisms of masked priming: A meta-analysis.

The extent to which unconscious information can influence behavior has been a topic of considerable debate throughout the history of psychology. A frequently used method for studying subliminal processing is the masked priming paradigm. The authors focused on studies in which this paradigm was used. Their aim was twofold: first, to assess the magnitude of subliminal priming across the literature and to determine whether subliminal primes are processed semantically, and second, to examine potential moderators of priming effects. The authors found significant priming in their analyses, indicating that unconsciously presented information can influence behavior. Furthermore, priming was observed under circumstances in which a nonsemantic interpretation could not fully explain the effects, suggesting that subliminally presented information can be processed semantically. Nonetheless, the nonsemantic processing of primes is enhanced and priming effects are boosted when the experimental context allows the formation of automatic stimulus–response mappings. This quantitative review also revealed several moderators that influence the strength of priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sandwich priming: A method for overcoming the limitations of masked priming by reducing lexical competitor effects.

An orthographically similar masked nonword prime facilitates responding in a lexical decision task (Forster & Davis, 1984). Recently, this masked priming paradigm has been used to evaluate models of orthographic coding—models that attempt to quantify prime-target similarity. One general finding is that priming effects often do not occur when prime-target similarity is moderate, a result that the authors interpret as being due to uncontrolled effects of lexical inhibition. In the present research, a new version of the masked priming paradigm, sandwich priming, was introduced in an effort to minimize the impact of lexical inhibition. Masked sandwich priming involves briefly presenting the target itself prior to the presentation of each prime. Results indicate that the new paradigm was successful. The predicted priming effects were observed for Guerrera and Forster’s (2008) T-All primes (e.g., avacitno–VACATION) and for primes differing from their targets at 3 letter positions (e.g., coshure–CAPTURE)—effects that are not found with the conventional masked priming paradigm. In addition to demonstrating the usefulness of the sandwich priming technique, these results also support the assumption that inhibitory processes play an important role in lexical processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Long-term semantic memory versus contextual memory in unconscious number processing.

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. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Playing chess unconsciously.

Expertise in a certain stimulus domain enhances perceptual capabilities. In the present article, the authors investigate whether expertise improves perceptual processing to an extent that allows complex visual stimuli to bias behavior unconsciously. Expert chess players judged whether a target chess configuration entailed a checking configuration. These displays were preceded by masked prime configurations that either represented a checking or a nonchecking configuration. Chess experts, but not novice chess players, revealed a subliminal response priming effect, that is, faster responding when prime and target displays were congruent (both checking or both nonchecking) rather than incongruent. Priming generalized to displays that were not used as targets, ruling out simple repetition priming effects. Thus, chess experts were able to judge unconsciously presented chess configurations as checking or nonchecking. A 2nd experiment demonstrated that experts' priming does not occur for simpler but uncommon chess configurations. The authors conclude that long-term practice prompts the acquisition of visual memories of chess configurations with integrated form-location conjunctions. These perceptual chunks enable complex visual processing outside of conscious awareness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Syllabic priming in lexical decision and naming tasks: The syllable congruency effect re-examined in French.

This study investigated the role of the syllable in visual recognition of French words. The syllable congruency procedure was combined with masked priming in the lexical-decision task (Experiments 1 and 3) and the naming task (Experiment 2). Target words were preceded by a nonword prime sharing the first three letters that either corresponded to the syllable (congruent condition), or not (incongruent condition). When primes were displayed for 67 ms, similar results were found in both the lexical decision and the naming tasks. Consonant-vowel targets such as BA.LANCE were recognised more rapidly in the congruent condition than in the incongruent and control conditions, while consonant-vowel-consonant targets such as BAL.CON were recognised more rapidly in the congruent and incongruent conditions than in the control condition. When a 43-ms SOA was used in the lexical-decision task, no significant priming effect was obtained. The results are discussed in an interactive-activation model incorporating syllable units. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Masked repetition priming and proportion effects under cognitive load.

The authors used a cognitive load manipulation (rehearsing a string of digits during the trial) to test the automaticity of (a) masked repetition priming and (b) the masked repetition proportion (RP) effect (i.e., greater priming when the proportion of repetition-prime trials is higher) in the lexical decision task. The RP (.2 vs. .8) was varied across blocks. Masked priming was not reduced under load compared with a no-load group. Surprisingly, only the load group showed an RP effect in response latencies, although the no-load group showed an RP effect in the error rates. Our results show that masked priming is automatic, yet the influence of masked primes can nonetheless be adjusted at an unconscious level. Implications for accounts of masked priming are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

From sunshine to double arrows: An evaluation window account of negative compatibility effects.

In category priming, target stimuli are to be sorted into 2 categories. Prime stimuli preceding targets typically facilitate processing of targets when primes and targets are members of the same category, relative to the case in which both stem from different categories, a positive compatibility effect (PCE). But negative compatibility effects (NCEs) are also sometimes observed. An evaluation window account (Klauer, Teige-Mocigemba, & Spruyt, 2009) of PCE and NCE in evaluative priming (category good versus category bad) is applied to masked arrow priming (Eimer & Schlaghecken, 1998; category left versus category right). Key principles of the account are that participants evaluate incoming evidence across a time window, and decisions about stimulus category are driven by changes in evidence weighted according to the Weber-Fechner law, leading to NCE for primes falling outside the time window and PCE for primes inside the time window. In Experiments 1–4, factors considered obligatory for NCE by current accounts of arrow priming are successively removed; yet, NCE remained intact as predicted by the evaluation window account. Furthermore, the evaluation window account, but none of the current accounts, predicts NCE without a stimulus intervening between prime and target at intermediate prime–target stimulus-onset asynchrony (Experiment 5) and when target onset comes as a surprise (Experiment 6). We conclude that the evaluation window account describes a hitherto overlooked mechanism that contributes to PCE and NCE in arrow priming and that it appears to generalize beyond the confines of evaluative priming to the diverse class of category-priming paradigms. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Unconscious Primes Activate Motor Codes Through Semantics.

Today, it is generally accepted that unconscious stimuli can activate a response code, which leads to a response congruency effect (RCE) on a subsequent target. However, it is not yet clear whether this is due to the semantic processing of the primes or to the formation of direct stimulus-response (S-R) associations bypassing the semantic system. Recently, it was shown that even novel primes, for which no direct S-R links exist, can also evoke an RCE that is in line with the activation of response codes through semantics. In these experiments, the authors examined 3 alternatives for this RCE from novel primes and report a novel effect in unconscious priming. First, the authors show that this effect is not limited to a small set of numerical stimuli but also extends to letter stimuli (Experiments 1-3). Second, the authors show that the RCE is not a side effect of the prime-target distance effect, as has been reported before (Experiments 1-2). Third, the authors found that, for RCE to occur, overlap at the motor level but not at the semantic level was crucial (Experiments 2-3). Finally, in addition, the results showed a category match priming effect independent of RCE. This last result is evidence that novel unconscious primes activate their semantic category prior to the target and might be considered a good marker for semantic processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Arousal contributions to affective priming: Electrophysiological correlates.

Current models of affective processing postulate that not only valence but also the arousal dimension characterizes the emotional experience. However, up-to-date research on affective priming has mainly focused on the contributions of valence congruency to priming. In this study, the authors explored the possible influence of arousal in priming processes. For this purpose, event-related potentials and reaction times were measured in response to high- and low-arousing positive targets that were either congruent or incongruent in arousal with a prime word. Priming arousal did not influence reaction times. By contrast, the processing of high-arousing targets was facilitated by a previous exposure to a congruent prime, as reflected by the reduction in the amplitude of a late positive component around 500 ms that has been thought to reflect attentional and memory processes. These results diverge from the findings of previous studies that primed valence and suggest a differential contribution of arousal and valence to affective priming. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Masked inhibitory priming in English: Evidence for lexical inhibition.

Predictions derived from the interactive activation (IA) model were tested in 3 experiments using the masked priming technique in the lexical decision task. Experiment 1 showed a strong effect of prime lexicality: Classifications of target words were facilitated by orthographically related nonword primes (relative to unrelated nonword primes) but were inhibited by orthographically related word primes (relative to unrelated word primes). Experiment 2 confirmed IA's prediction that inhibitory priming effects are greater when the prime and target share a neighbor. Experiment 3 showed a minimal effect of target word neighborhood size (N) on inhibitory priming but a trend toward greater inhibition when nonword foils were high-N than when they were low-N. Simulations of 3 different versions of the IA model showed that the best fit to the data is produced when lexical inhibition is selective and when masking leads to reset of letter activities. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

A study of relative-position priming with superset primes.

Four lexical decision experiments are reported that use the masked priming paradigm to study the role of letter position information in orthographic processing. In Experiments 1 and 2, superset primes, formed by repetition of 1 or 2 letters of the target (e.g., jusstice-JUSTICE) or by insertion of 1 or 2 unrelated letters (e.g., juastice-JUSTICE), generated significant priming compared with unrelated primes and did not differ significantly from an identity priming condition. In Experiment 3, identity primes generated significantly faster responses than subset primes formed by removal of 2 letters from the target (e.g., jutie-JUSTICE), and subset primes generated faster responses than substitution primes formed by substitution of 2 letters of the target with unrelated letters (e.g., jumlice-JUSTICE). In Experiment 4, insertion of 3 unrelated letters continued to generate facilitation relative to unrelated primes but significantly less so than the identity prime condition. The authors discuss the implications of these results for letter-position coding schemes. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Masked Repetition and Phonological Priming Within and Across Modalities.

Lexical decision latencies to word targets presented either visually or auditorily were faster when directly preceded by a briefly presented (53-ms) pattern-masked visual prime that was the same word as the target (repetition primes), compared with different word primes. Primes that were pseudohomophones of target words did not significantly influence target processing compared with unrelated primes (Experiments 1-2) but did produce robust priming effects with slightly longer prime exposures (67 ms) in Experiment 3. Like repetition priming, these pseudohomophone priming effects did not interact with target modality. Experiments 4 and 5 replicated this general pattern of effects while introducing a different measure of prime visibility and an orthographic priming condition. Results are interpreted within the framework of a bimodal interactive activation model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Stimulus–response compatibility as a function of stimulus code and response modality.

The concept of stimulus-response compatibility can be differentiated into set-level and element-level compatibility. The relation between these 2 types of compatibility was examined by varying stimulus code (spatial or verbal) and response modality (manual or vocal) in 2-choice tasks that used left-right stimuli and left-right responses. Element-level compatibility was an increasing function of set-level compatibility and larger for verbal than for spatial stimuli. The positive relation between set- and element-level compatibility was due to differences for the congruent mapping but not the incongruent mapping. The results can be characterized in terms of (a) a continuum along which the relative compatibility of the responses with spatial and verbal stimuli varies and (b) a dual-route conception of response selection in which a direct, or automatic, route is involved only when a congruent mapping is in effect. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Cross-modal evaluative priming: Emotional sounds influence the processing of emotion words.

Cross-modal priming occurs when a prime presented in one sensory modality influences responses to a target in a different sensory modality. Currently, demonstrations of cross-modal evaluative priming have been sparse and limited. In the present study, we seek to partially rectify this state of affairs by examining cross-modal evaluative priming from auditory primes to visual targets. Significant cross-modal priming effects were found, but only for negative primes. Results are discussed in terms of the negativity bias, and several suggestions are provided for using cross-modal evaluative priming to address theoretically important questions about emotion and cognition. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Verbs and nouns are organized and accessed differently in the mental lexicon: evidence from Hebrew

A masked priming paradigm was used to examine the role of the root and verbal-pattern morphemes in lexical access within the verbal system of Hebrew. Previous research within the nominal system had showed facilitatory effects from masked primes that shared the same root as the target word, but not when the primes shared the word pattern (R. Frost, K. I. Forster, & A. Deutsch, 1997). In contrast to these findings, facilitatory effects were obtained for both roots and word patterns in the verbal system. In addition, verbal pattern facilitation was obtained even when the primes were pseudoverbs consisting of illegal combinations of roots and verbal patterns. Significant priming was also found when the primes and the targets contained the same root. The results are discussed with reference to the factors that may determine the lexical status of morphological units in lexical organization. A model of morphological processing of Hebrew words is proposed.     

An accrual model for primed digit classification.

This article describes a chronometric experiment of digit classification with masked primes. EEG experiments have shown that the subliminal prime activates the cortex prior to the target signal, thusly modifying the response: Congruent primes lead to faster correct answers, while incongruent primes result in slower response. It is noticed that incorrect answers show an inverted effect: A congruent prime inhibits incorrect answers, and the reverse for incongruent primes. Within the evidence accrual paradigm, it is suggested that the prime activity in the motor cortex effectively behaves as a shift in the decision threshold. This model assumption is consistent with our experimental findings. The correct and incorrect answers and the error percentage are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Priming processes in the Simon task: More evidence from the lexical decision task for a third route in the Simon effect.

Recently, it was proposed that the Simon effect would result not only from two interfering processes, as classical dual-route models assume, but from three processes. It was argued that priming from the spatial code to the nonspatial code might facilitate the identification of the nonspatial stimulus feature in congruent Simon trials. In the present study, the authors provide evidence that the identification of the nonspatial information can be facilitated by the activation of an associated spatial code. In three experiments, participants first associated centrally presented animal and fruit pictures with spatial responses. Subsequently, participants decided whether laterally presented letter strings were words (animal, fruit, or other words) or nonwords; stimulus position could be congruent or incongruent to the associated spatial code. As hypothesized, animal and fruit words were identified faster at congruent than at incongruent stimulus positions from the association phase. The authors conclude that the activation of the spatial code spreads to the nonspatial code, resulting in facilitated stimulus identification in congruent trials. These results speak to the assumption of a third process involved in the Simon task. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Qualitative Differences Between Conscious and Nonconscious Processing? On Inverse Priming Induced by Masked Arrows.

In general, both consciously and unconsciously perceived stimuli facilitate responses to following similar stimuli. However, masked arrows delay responses to following arrows. This inverse priming has been ascribed to inhibition of premature motor activation, more recently even to special processing of nonconsciously perceived material. Here, inverse priming depended on particular masks, was insensitive to contextual requirements for increased inhibition, and was constant across response speeds. Putative signs of motor inhibition in the electroencephalogram may as well reflect activation of the opposite response. Consequently, rather than profiting from inhibition of primed responses, the alternative response is directly primed by perceptual interactions of primes and masks. Thus there is no need to assume separate pathways for nonconscious and conscious processing. (PsycINFO Database Record (c) 2010 APA, all rights reserved)