Masked Priming Research Articles

Scrutinizing subliminal priming of numbers in the dissociation paradigm

Abstract Unconscious response priming has been amply reported in studies adopting the dissociation paradigm, in which heavily masked prime stimuli modulate responses to targets (giving rise to a significant priming effect, mostly measured in reaction times, RT), whilst participants cannot classify the prime stimuli above chance level (e.g., measured in percent correct). The dissociation (significant priming effect vs. chance-level prime classification) is assumed to indicate that, even when participants are not consciously aware of the primes, they are nonetheless perceived and processed. Such purported dissociation, however, is predominantly based on a methodological problem of inequivalent metrics. We illustrated the problem by replicating and extending the behavioral part of Dehaene et al. (1998, Nature): In the masked priming experiment, one-digit numbers were visually presented as primes and targets. Participants judged whether target numbers were smaller or larger than 5. Subsequently, they were asked to ignore targets and classify heavily masked primes as smaller or larger than 5. The prime duration was manipulated by parametrically varying prime-mask stimulus onset asynchrony (SOA, from 10 milliseconds [ms] to 80 ms by 10 ms). At SOA=40 ms, a highly significant congruency priming effect (in RT difference) emerged, whereas prime classification (in percent correct) approximated chance-level. Upon closer inspection, however, no dissociation was found when the priming effect and prime classification performance was estimated in the same metric (e.g., in percent correct). Nor did a dissociation between priming task performance and prime classification performance arise at any other SOA. Furthermore, performance on prime classification increased monotonically along with increasing SOAs (from 20 ms upwards), which argues against chance-level prime classification at SOA=40 ms. In conclusion, performance dissociation, from which perception without awareness is to be derived, may purport to exist when the priming effect and prime classification is not compared in a shared metri Meeting abstract presented at VSS 2015.

Human brain mapping of theta-band behavioral oscillations in masked priming

Human brain mapping of theta-band behavioral oscillations in masked priming

How do bilinguals identify the language of the words they read?

How do bilinguals detect the language of the words they read? Recent electrophysiological research using the masked priming paradigm combining primes and targets from different languages has shown that bilingual readers identify the language of the words within approximately 200ms. Recent evidence shows that language-detection mechanisms vary as a function of the orthographic markedness of the words (i.e., whether or not a given word contains graphemic combinations that are not legal in the other language). The present study examined how the sub-lexical orthographic regularities of words are used as predictive cues. Spanish–Basque bilinguals and Spanish monolinguals (control group) were tested in an Event-Related Potential (ERP) experiment, using the masked priming paradigm. During the experiment, Spanish targets were briefly preceded by unrelated Spanish or Basque words. Unrelated Basque words could contain bigram combinations that are either plausible or implausible in the target language (Spanish). Results show a language switch effect in the N250 and N400 components for marked Basque primes in both groups, whereas, in the case of unmarked Basque primes, language switch effects were found in bilinguals but not monolinguals. These data demonstrate that statistical orthographic regularities of words play an important role in bilingual language detection, and provide new evidence supporting the assumptions of the BIA+ extended model.

Editorial: Frontiers in the acquisition of literacy.

Editorial: Frontiers in the acquisition of literacy.

Early semantic activation in a semantic categorization task with masked primes: Cascaded or not?

The assumption that activation is cascaded implies that the semantic properties of all neighbors of the input word are activated to varying degrees. This assumption is tested using masked priming in a semantic categorization experiment, where the prime belongs to the same category as the target (a congruent prime), or to a different category (an incongruent prime). In Experiment 1, the prime was a nonword neighbor of an exemplar or non-exemplar of the category, and a clear congruence effect was produced, even though the orthographic overlap was fairly low (e.g., lucchibi-zucchini). In Experiment 2, the prime was a word neighbor (e.g., capable-cabbage), which eliminates the possibility that the prime was simply interpreted as equivalent to the nearest task-relevant word, but a congruence effect was still obtained. Experiment 3 replicated this effect. Experiments 4–6 investigated the possible role of the category using a two-alternative forced choice discrimination task, where the task was simply to guess which of two subsequently presented words was more similar in meaning to the masked word. Despite better than chance performance when the masked word was related to one of the alternatives, performance was at chance when the masked word was a neighbor of a word that was related to one of the alternatives, indicating that semantic activation is not normally cascaded. It is concluded that the categorization task fundamentally alters the way in which a masked word is processed.

Fluency can bias masked priming of binary judgments: evidence from an all-nonword task.

Using a novel all-nonword task ("Does the target have more vowels than consonants?"), new evidence is provided showing that processing fluency can bias masked priming of binary judgments. Two experiments revealed masked repetition priming for "yes" nonwords (e.g., NUISO) but not for "no" nonwords (e.g., RULON). This pattern is considered evidence that the greater ease of target processing induced by repetition primes was attributed to the target being a member of the response category associated with shorter RTs, namely the "yes" response category. This pattern of nonword priming effects reinforces Bodner and Masson's (1997) key claims: (a) a fluency-attribution process can influence masked priming, and (b) therefore, the masked-priming paradigm does not isolate lexical processes.

The Time Course for Processing Vowels and Lexical Tones: Reading Aloud Thai Words.

Three naming aloud experiments and a lexical decision (LD) experiment used masked priming to index the processing of written Thai vowels and tones. Thai allows for manipulation of the mapping between orthography and phonology not possible in other orthographies, for example, the use of consonants, vowels and tone markers in both horizontal and vertical orthographic positions (HOPs and VOPs). Experiment I showed that changing a vowel between prime and target slowed down target naming but changing a tone mark did not. Experiment I used an across item-design and a different number of HOPs in the way vowels and tones were specified. Experiment 2 used a within-item design and tested vowel and tone changes for both 2-HOP and 3-HOP targets separately. The 3-HOP words showed the same tone and vowel change effect as Experiment 1, whereas 2-HOP items did not. It was speculated that the 2-HOP result was due to the variable position of the vowel affecting priming. Experiment 3 employed a more stringent control over the 2-HOP vowel and tone items and found priming for the tone changes but not for vowel changes. The final experiment retested the items from Experiment 3 with the LD task and found no priming for the tone change items, indicating that the tone effect in Experiment 3 was due to processes involved in naming aloud. In all, the results supported the view that for naming a word, the development of tone information is slower than vowel information.

Resolving the locus of cAsE aLtErNaTiOn effects in visual word recognition: Evidence from masked priming

Determining the factors that modulate the early access of abstract lexical representations is imperative for the formulation of a comprehensive neural account of visual-word identification. There is a current debate on whether the effects of case alternation (e.g., tRaIn vs. train) have an early or late locus in the word-processing stream. Here we report a lexical decision experiment using a technique that taps the early stages of visual-word recognition (i.e., masked priming). In the design, uppercase targets could be preceded by an identity/unrelated prime that could be in lowercase or alternating case (e.g., table-TABLE vs. crash-TABLE; tAbLe-TABLE vs. cRaSh-TABLE). Results revealed that the lowercase and alternating case primes were equally effective at producing an identity priming effect. This finding demonstrates that case alternation does not hinder the initial access to the abstract lexical representations during visual-word recognition.

Masked primes activate feature representations in reading aloud.

Theories of reading aloud are silent about the role of subphonemic/subsegmental representations in translating print to sound. However, there is empirical evidence suggesting that feature representations are activated in speech production and visual word recognition. In the present study, we sought to determine whether masked primes activate feature representations in reading aloud using a variation of the masked onset priming effect (MOPE). We found that target nonwords (e.g., BAF) were read aloud faster when preceded by masked nonword primes that shared their initial phoneme with the target (e.g., bez), or primes whose initial phoneme shared all features except voicing with the first phoneme of the target (e.g., piz), compared with unrelated primes (e.g., suz). We obtained the same result in 2 experiments that used different participants and prime durations (around 60 ms in Experiment 1 and 50 ms in Experiment 2). The significant masked feature priming effect that was observed in both experiments converges with the empirical evidence in the speech production and visual word recognition domains indicating a functional role for features in reading aloud. Our findings motivate the further development of current theories of reading aloud and have important implications for extant theories of speech production.

The L2 decomposition of transparent derived verbs - Is it 'morphological'? A commentary on De Grauwe, Lemhöfer, Willems, & Schriefers (2014).

The L2 decomposition of transparent derived verbs - Is it 'morphological'? A commentary on De Grauwe, Lemhöfer, Willems, & Schriefers (2014).

Morphological Decomposition in Japanese De-adjectival Nominals: Masked and Overt Priming Evidence.

Whether morpheme-based processing extends to relatively unproductive derived words remains a matter of debate. Although whole-word storage and access has been proposed for some derived words, such as Japanese de-adjectival nominals with the unproductive (-mi) suffix (e.g., Hagiwara etal. in Language 75:739-763, 1999), Clahsen and Ikemoto (Ment Lex 7:147-182, 2012) found masked priming from de-adjectival nominals with productive (-sa) and unproductive (-mi) suffixes to their adjectivally-inflected base morpheme. Using masked and unmasked priming, we examine whether adjectivally-inflected base morpheme primes facilitate the processing of Japanese de-adjectival nominal targets with a productive or unproductive affix, including an orthographic-overlap condition and semantic relatedness measure that Clahsen and Ikemoto (2012) did not include. Our results replicate and extend Clahsen and Ikemoto (2012), revealing significant, statistically-equivalent morphological priming effects for -sa and -mi affixed targets, independent of orthographic and semantic relatednesss, suggesting that the processing of derived words with the unproductive -mi affix makes recourse to morpheme-level representations.

The temporal dynamic of automatic inhibition of irrelevant actions.

Motor inhibition can occur even without conscious perception and any voluntary effort. Although it is now clear that such an inhibitory process needs time to unfold, its exact temporal dynamic remains to be elucidated. Therefore, the present study aims to examine the impact of various temporal factors on automatic motor inhibition using the masked priming task. Results show that this process can be modulated by any factor that introduces time between the mask onset and the execution of target response, whether it stems from a purely external origin (mask-target stimulus-onset asynchrony [SOA]), a purely internal origin (spontaneous reaction time [RT] fluctuations), or a mix of both (RT fluctuations from the target sequence). Moreover, when the external temporal factor could not determine the direction of prime influence, the RT fluctuations had the strongest impact on the priming effect. These RT fluctuations are plausibly the result of spontaneous trial-to-trial changes from more impulsive and error-prone decisions to more cautious and accurate decisions to the target. Indeed, both accuracy and speed were equally required during the task, but both requirements are impossible to achieve perfectly in every trial. This suggests that fluctuations in the level of caution in voluntary decisions can modulate unconscious and involuntary motor inhibition.

Age Constraints on L2 Learners’ Processing of Derivational Morphology

This study examined how L2 learners of English process morphologically complex words (e.g., bareness) and psuedowords (e.g.,*boilness) to investigate if the L2 processing of derivational morphology is subject to critical period effects. It has been claimed that native speakers rely on procedural memory to process morphologically complex words, while L2 learners tend to utilize declarative memory to process them (Ullman, 2001, 2004, 2005). According to Ullman, L2 learners’ reliance on declarative memory for processing morphologically complex words is due to maturational changes in procedural memory. Two related experiments with a masked priming lexical decision task were conducted with two groups of Korean learners: early and late L2 learners. With regard to the results, early L2 learners showed stem priming effects for morphologically related prime-target pairs, which is indicative of morphological decomposition. On the other hand, late L2 learners did not provide any evidence of stem priming, indicating that they might have processed the morphologically complex word/pseudoword as a whole unit. These data suggest that the L2 processing of late learners is different from that of early learners.

Unconscious manipulation of free choice by novel primes.

The extent to which non-conscious perception can influence behaviour has been a topic of considerable controversy in psychology for decades. Although a challenging task, convincing empirical demonstrations have emerged suggesting that non-consciously perceived 'prime' stimuli can influence motor responses to subsequent targets. Interestingly, recent studies have shown that the influence of masked primes is not restricted to target-elicited responses, but can also bias free-choices between alternative behaviours. The present experiment extends these findings by showing that free-choices could also be biased by novel primes that never appeared as targets and therefore could not trigger acquired stimulus-response (S-R) mappings. This new evidence suggests that free-choice behaviour can be influenced by non-consciously triggered semantic representations. Furthermore, the results reported here support accounts of masked priming that posit an automatic semantic categorisation of non-consciously perceived visual stimuli.

Must analysis of meaning follow analysis of form? A time course analysis.

Many models of word recognition assume that processing proceeds sequentially from analysis of form to analysis of meaning. In the context of morphological processing, this implies that morphemes are processed as units of form prior to any influence of their meanings. Some interpret the apparent absence of differences in recognition latencies to targets (SNEAK) in form and semantically similar (sneaky-SNEAK) and in form similar and semantically dissimilar (sneaker-SNEAK) prime contexts at a stimulus onset asynchrony (SOA) of 48 ms as consistent with this claim. To determine the time course over which degree of semantic similarity between morphologically structured primes and their targets influences recognition in the forward masked priming variant of the lexical decision paradigm, we compared facilitation for the same targets after semantically similar and dissimilar primes across a range of SOAs (34–100 ms). The effect of shared semantics on recognition latency increased linearly with SOA when long SOAs were intermixed (Experiments 1A and 1B) and latencies were significantly faster after semantically similar than dissimilar primes at homogeneous SOAs of 48 ms (Experiment 2) and 34 ms (Experiment 3). Results limit the scope of form-then-semantics models of recognition and demonstrate that semantics influences even the very early stages of recognition. Finally, once general performance across trials has been accounted for, we fail to provide evidence for individual differences in morphological processing that can be linked to measures of reading proficiency.

Experience a conflict-either consciously or not (commentary on Desender, Van Opstal, and Van den Bussche, 2014).

Experience a conflict-either consciously or not (commentary on Desender, Van Opstal, and Van den Bussche, 2014).

Is conflict adaptation an illusion?

Is conflict adaptation an illusion?

The relationship between morphological awareness and morphological decomposition among English language learners

Morphological awareness facilitates many reading processes. For this reason, L1 and L2 learners of English are often directly taught to use their knowledge of English morphology as a useful reading strategy for determining parts of speech and meaning of novel words. Over time, use of morphological awareness skills while reading develops into an automatic process for L1 readers called morphological decomposition. While the practice of explicitly teaching morphological awareness skills is prevalent in ESL classes, more research is needed to establish what is known about gains in L2 morphological awareness, and its relationship to the development of automatic morphological decomposition processes in English language learners. The present study seeks to shed light on the nature of this relationship across growth in L2 proficiency. Two experimental measures were used: a masked priming paradigm with a lexical decision task to explore priming evidence for morphological decomposition and a paper and pencil test of morphological awareness which required subjects to derive the base of a morphologically complex word. These tasks were administered to L1 (N = 43) and L2 groups (intermediate N = 16, advanced N = 16) of university-aged subjects. Results indicated that all subjects show repetition priming effects. However, despite a significant gain in explicit knowledge of English morphology across proficiency levels, L2 learners don’t develop an ability to morphologically decompose words in the unconscious, automatic way that native English speakers do, as evidenced by a lack of morphological priming. Implications for L2 pedagogy and L2 word storage in the mental lexicon are discussed.

Is conflict adaptation triggered by feature repetitions? An unexpected finding.

For decades, cognitive adaptation to response conflict has been considered to be the hallmark of cognitive control. Notwithstanding a vast amount of evidence ruling out low-level interpretations of these findings, disbelief still exists with regard to the underlying cause of the observed effects. Especially when considering cognitive adaptation to unconscious conflict, it is still a matter of debate whether repetitions of features between trials might explain this intriguing finding rather than the involvement of unconscious control. To this purpose, we conducted two masked priming experiments in which four different responses to four different stimuli were required. This allowed us to completely eliminate repetitions of prime and target over consecutive trials. Independent of whether conflicting information was presented clearly visible or almost imperceptible, the results showed an unexpected pattern. Contrary to the regular congruency sequence effect (CSE; i.e., classic Gratton effect), in both experiments the congruency effect increased following incongruent trials. Interestingly, this reversed effect completely disappeared when we eliminated all trials with feature repetitions from the analysis. A third experiment, in which feature repetitions were excluded a priori, showed a small but regular CSE in the error rates only. Given that feature repetitions are theoretically thought to create a regular CSE, our results are not in line with an interpretation in terms of feature repetitions nor with an interpretation in terms of cognitive control. We conclude that examining cognitive adaptation with or without feature repetitions might be more difficult to conceive than is often suggested in the literature.

Real-time functional architecture of visual word recognition.

Despite a century of research into visual word recognition, basic questions remain unresolved about the functional architecture of the process that maps visual inputs from orthographic analysis onto lexical form and meaning and about the units of analysis in terms of which these processes are conducted. Here we use magnetoencephalography, supported by a masked priming behavioral study, to address these questions using contrasting sets of simple (walk), complex (swimmer), and pseudo-complex (corner) forms. Early analyses of orthographic structure, detectable in bilateral posterior temporal regions within a 150-230 msec time frame, are shown to segment the visual input into linguistic substrings (words and morphemes) that trigger lexical access in left middle temporal locations from 300 msec. These are primarily feedforward processes and are not initially constrained by lexical-level variables. Lexical constraints become significant from 390 msec, in both simple and complex words, with increased processing of pseudowords and pseudo-complex forms. These results, consistent with morpho-orthographic models based on masked priming data, map out the real-time functional architecture of visual word recognition, establishing basic feedforward processing relationships between orthographic form, morphological structure, and lexical meaning.