Being forward not backward: lexical limits to masked priming

This study investigated whether masked priming is mediated by existing memory representations by determining whether nonwords targets would show repetition priming. To avoid the potential confound that nonword repetition priming would be obscured by a familiarity response bias, the standard lexical decision and naming tasks were modified to make targets unfamiliar. Participants were required to read a target string from right to left (i.e., "ECAF" should be read as "FACE") and then make a response. To examine if priming was based on lexical representations, repetition primes consisted of words when read forwards or backwards (e.g., "face", "ecaf") and nonwords (e.g., "pame", "emap"). Forward and backward primes were used to test if task instruction affected prime encoding. The lexical decision and naming tasks showed the same pattern of results: priming only occurred for forward primes with word targets (e.g., "face-ECAF"). Additional experiments to test if response priming affected the LDT indicated that the lexical status of the prime per se did not affect target responses. These results showed that the encoding of masked primes was unaffected by the novel task instruction and support the view that masked priming is due to the automatic triggering of pre-established computational processes based on stored information.     

Facilitation versus inhibition in the masked priming same–different matching task

In the past years, growing attention has been devoted to the masked priming same–different task introduced by Norris and Kinoshita (2008 Norris, D. and Kinoshita, S. 2008. Perception as evidence accumulation and Bayesian inference: Insights from masked priming. Journal of Experimental Psychology: General, 137: 433–455. [Crossref], [Web of Science ®] , [Google Scholar], Journal of Experimental Psychology: General). However, a number of researchers have raised concerns on the nature of the cognitive processes underlying this task—in particular the suspicion that masked priming effects in this task are mostly inhibitory in nature and may be affected by probe–prime contingency. To examine the pattern of facilitative/inhibitory priming effects in this task, we conducted two experiments with an incremental priming paradigm using four stimulus–onset asynchronies (13, 27, 40, and 53 ms). Experiment 1 was conducted under a predictive-contingency scenario (probe–prime–target; i.e., “same” trials: HOUSE–house–HOUSE vs. house–water–HOUSE; “different” trials: field–house–HOUSE vs. field–water–HOUSE), while Experiment 2 employed a zero-contingency scenario (i.e., “same” trials: HOUSE–house–HOUSE vs. house–water–HOUSE; “different” trials: field–field–HOUSE vs. field–water–HOUSE). Results revealed that, for “same” responses, both facilitation and inhibition increased linearly with prime duration in the two scenarios, whereas the pattern of data varied for “different” responses, as predicted by the Bayesian Reader model.     

Are coffee and toffee served in a cup? Ortho-phonologically mediated associative priming

We report three masked associative priming experiments with the lexical decision task that explore whether the initial activation flow of a visually presented word activates the semantic representations of that word's orthographic/phonological neighbours. The predictions of cascades and serial/modular models of lexical processing differ widely in this respect. Using a masked priming paradigm (stimulus onset asynchrony, SOA = 50 ms), words preceded by ortho-phonologically mediated associated “neighbours” (oveja–MIEL, the Spanish for sheep–HONEY; note that oveja is a phonological neighbour of abeja, the Spanish for bee) were recognized more rapidly than words preceded by an unrelated word prime (Experiments 1 and 3). Furthermore, the magnitude of the ortho-phonologically mediated priming effect (oveja–MIEL) was similar to the magnitude of the associative priming effect (abeja–MIEL). With visible primes and a 250-ms SOA, only the directly associated words showed a priming effect (Experiment 2). These findings pose some problems for a modular account and are more easily interpreted in terms of cascaded models.     

Code-switching effects in bilingual word recognition: a masked priming study with event-related potentials

Two experiments tested language switching effects with bilingual participants in a priming paradigm with masked primes (duration of 50 ms in Experiment 1 and 100 ms in Experiment 2). Participants had to monitor target words for animal names, and ERPs were recorded to critical (non-animal) words in L1 and L2 primed by unrelated words from the same or the other language. Both experiments revealed language priming (switching) effects that depended on target language. For target words in L1, most of the language switch effect appeared in the N400 ERP component, with L2 primes generating a more negative going wave than L1 primes. For L2 target words, on the other hand, the effects of a language switch appeared mainly in an earlier ERP component (N250) peaking at approximately 250 ms post-target onset, and showing greater negativity following an L1 prime than an L2 prime. This is the first evidence for fast-acting language-switching effects occurring in the absence of overt task switching.     

Tracking the acquisition of orthographic skills in developing readers: masked priming effects

A masked priming procedure was used to explore developmental changes in the tuning of lexical word recognition processes. Lexical tuning was assessed by examining the degree of masked form priming and used two different types of prime-target lexical similarity: one letter different (e.g., rlay-->PLAY) and transposed letters (e.g., lpay-->PLAY). The performance of skilled adult readers was compared with that of developing readers in Grade 3. The same children were then tested again two years later, when they were in Grade 5. The skilled adult readers showed no form priming, indicating that their recognition mechanisms for these items had become finely tuned. In contrast, the Grade 3 readers showed substantial form priming effects for both measures of lexical similarity. When retested in Grade 5, the developing readers no longer showed significant one letter different priming, but transposed letter priming remained. In general, these results provide evidence for a transition from more broadly tuned to more finely tuned lexical recognition mechanisms and are interpreted in the context of models of word recognition.     

Priming of abstract letter identities in the letter match task

Previous studies of letter recognition have not found priming for abstract letter identities. We used a task that required participants to decide whether a target is the same or different from a reference letter presented in opposite case, which avoids the shortcomings of tasks used in previous studies. We found robust priming effects in this task, which were the same size for letter pairs that have similar visual features across case (e.g., c/C, x/X) and dissimilar features (e.g., a/A, b/B). Also, the pattern of priming was the same whether the prime was in the same or different case as the reference. We take these findings as evidence that abstract letter identities support priming in this task. We suggest that the same–different match task is a useful tool for studying representations used to support masked priming in letter recognition and with other stimuli with limited set size.     

Influence of prime lexicality,frequency, and pronounceability on the masked onset priming effect

The present study investigates the origins of the masked onset priming effect (MOPE). There are two alternative interpretations that account for most of the evidence reported on the MOPE, so far. The speech planning account (SP) identifies the locus of the MOPE in the preparation of the speech response. In contrast, the dual-route theory proposes that the effect arises as a result of the processing of the prime by the nonlexical route. In a series of masked onset priming word naming experiments we test the validity of these accounts by manipulating the primes' frequency, their lexical status, and pronounceability. We found consistent MOPEs of similar magnitude with high- and low-frequency prime words as well as with pronounceable nonwords. Contrarily, when primes consisted of unpronounceable consonantal strings the effect disappeared, suggesting that pronounceability of the prime is a prerequisite for the emergence of the MOPE. These results are in accordance with the predictions of the SP account. The pattern of effects obtained in the present study further defines the origins of the MOPE.     

Visual experience is not necessary for efficient survey spatial cognition: Evidence from blindness

This study investigated whether the lack of visual experience affects the ability to create spatial inferential representations of the survey type. We compared the performance of persons with congenital blindness and that of blindfolded sighted persons on four survey representation-based tasks (Experiment 1). Results showed that persons with blindness performed better than blindfolded sighted controls. We repeated the same tests introducing a third group of persons with late blindness (Experiment 2). This last group performed better than blindfolded sighted participants, whereas differences between participants with late and congenital blindness were nonsignificant. The present findings are compatible with results of other studies, which found that when visual perception is lacking, skill in gathering environmental spatial information provided by nonvisual modalities may contribute to a proper spatial encoding. It is concluded that, although it cannot be asserted that total lack of visual experience incurs no cost, our findings are further evidence that visual experience is not a necessary condition for the development of spatial inferential complex representations.     

Masked form priming is moderated by the size of the letter-order-free orthographic neighbourhood

University students made lexical decisions to targets preceded by masked primes. In Experiment 1, transposed-letter primes were used also in the sandwich priming paradigm, in which the target is briefly pre-presented prior to the prime. The priming effects in the masked paradigm, but not in the sandwich paradigm, were moderated by the density of the letter-order-free neighbourhood of the target. In Experiment 2, letter-order-free neighbour prime words produced a priming cost in masked priming. These results are consistent with the idea that sandwich priming attenuates letter-order-free neighbour competition in target identification. Unexpectedly, no priming cost was produced by conventional (letter-position-preserving) word neighbour primes. Order-free neighbours may produce facilitation of target processing less, and more variably, than conventional neighbours.     

Subliminal repetition primes help detection of phonemes in a picture: Evidence for a phonological level of the priming effects

In this research, we combine a cross-form word–picture visual masked priming procedure with an internal phoneme monitoring task to examine repetition priming effects. In this paradigm, participants have to respond to pictures whose names begin with a prespecified target phoneme. This task unambiguously requires retrieving the word-form of the target picture's name and implicitly orients participants' attention towards a phonological level of representation. The experiments were conducted within Spanish, whose highly transparent orthography presumably promotes fast and automatic phonological recoding of subliminal, masked visual word primes. Experiments 1 and 2 show that repetition primes speed up internal phoneme monitoring in the target, compared to primes beginning with a different phoneme from the target, or sharing only their first phoneme with the target. This suggests that repetition primes preactivate the phonological code of the entire target picture's name, hereby speeding up internal monitoring, which is necessarily based on such a code. To further qualify the nature of the phonological code underlying internal phoneme monitoring, a concurrent articulation task was used in Experiment 3. This task did not affect the repetition priming effect. We propose that internal phoneme monitoring is based on an abstract phonological code, prior to its translation into articulation.     

A unique look at face processing: the impact of masked faces on the processing of facial features

This experiment utilized a masked priming paradigm to explore the early processes involved in face recognition. The first experiment investigated implicit processing of the eyes and mouth in an upright face, using prime durations of 33 and 50 ms. The results demonstrate implicit processing of both the eyes and mouth, and support the configural processing theory of face processing. The second experiment used the same method with inverted faces and the third experiment was a combination of Experiments 1 and 2. The fourth experiment utilized misaligned faces as the primes. Based on the pattern of results from these experiments, we suggest that, when a face is inverted, the eyes and mouth are initially processed individually and are not linked until a later stage of processing. An upright face is proposed to be processed by analysis of its configuration, whereas an inverted face is initially processed using first-order relational information, and then converted to an upright representation and transferred to face specific regions for configural analysis.     

Conceptual and perceptual factors in the picture superiority effect

This study tested the hypothesis that separate mechanisms mediate the planning of reaching and keypress responses. Participants performed a spatial precueing task with two preparation intervals (100 ms and 1000 ms) and three response sets: (a) pressing one of four response keys; (b) reaching with one of two hands; and (c) reaching with one hand. Reaction time results showed a pattern of precueing effects that strongly depended on the number of effectors in the response set and on the preparation interval. This outcome was interpreted as evidence that distinct mechanisms mediate the planning of multiple-effector and single-effector actions, with effector selection being relevant in the former but not in the latter. The theoretical implications of this conclusion are discussed.     

Lexicality, morphological structure, and semantic transparency in the processing of German ver-verbs: The complementarity of on-line and off-line evidence

Two types of experiments investigate the visual on-line and off-line processing of German ver-verbs (e.g., verbittern ‘to embitter'). In Experiments 1 and 2 (morphological priming), latency patterns revealed the existence of facilitation effects for the morphological conditions (BITTER-VERBITTERN and BITTERN-VERBITTERN) as compared to the neutral conditions (SAUBER-VERBITTERN and SÄUBERN-VERBITTERN). In Experiments 3 and 4 (rating tasks) participants had to judge whether the target (VERBITTERN) “comes from,” “contains a form of,” or “contains the meaning of” the root (BITTER) or the root+en substring (BITTERN). Taken together, these studies revealed the combined influence of the three factors of lexicality (real word status), morphological structure, and semantic transparency.     

Masked semantic priming effects from the prime's orthographic neighbours

The present research involved masked priming lexical decision experiments using, in the crucial condition, masked primes with an orthographic neighbour that was semantically related to the target. Regardless of the lexicality of the prime, a significant priming effect was observed when the relatedness proportion (RP, that is, the proportion of primes and targets that were directly related on the “word” trials) was 2/3 (Experiments 1 and 2). No effect emerged, however, when the RP was 0 (Experiment 3). These results indicate that lexical/semantic activation arises automatically for both the prime and its neighbours. This activated lexical/semantic information appears to be evaluated together with the lexical/semantic information activated by the target, creating a decision bias during the decision-making process, but only when that information often provides a clue as to the nature of the correct decision. Our results, therefore, also provide support for the retrospective account of masked semantic priming.     

Neural circuitry of the bilingual mental lexicon: Effect of age of second language acquisition

Numerous studies have proposed that changes of the human language faculty caused by neural maturation can explain the substantial differences in ultimate attainment of grammatical competences between first language (L1) acquirers and second language (L2) learners. However, little evidence on the effect of neural maturation on the attainment of lexical knowledge in L2 is available. The present functional magnetic resonance study addresses this question via a cross-linguistic neural adaptation paradigm. Age of acquisition (AoA) of L2 was systematically manipulated. Concrete nouns were repeated across language (e.g., French–German, valise^suitcase–Koffer^suitcase). Whereas early bilinguals (AoA of L2 < 3 years) showed larger repetition enhancement (RE) effects in the left superior temporal gyrus, the bilateral superior frontal gyrus and the right posterior insula, late bilinguals (AoA of L2 > 10 years) showed larger RE effects in the middle portion of the left insula and in the right middle frontal gyrus (MFG). We suggest that, as for grammatical knowledge, the attainment of lexical knowledge in L2 is affected by neural maturation. The present findings lend support to neurocognitive models of bilingual word recognition postulating that, for both early and late bilinguals, the two languages are interconnected at the conceptual level.     

Is morphological decomposition limited to low-frequency words?

On the basis of data from masked priming experiments, it has been argued that an automatic process of decomposition is applied to all morphologically structured stimuli, irrespective of their lexical characteristics (Rastle, Davis, & New, 2004). So far, this claim has been tested only with respect to low-frequency primes and nonword primes. This is a limitation because some models of morphological processing postulate that only high-frequency complex words are recognized as whole forms. Thus, a more stringent test would be to determine whether high-frequency complex words also show evidence of masked priming. We report an experiment that compares masked-priming effects observed when the primes constitute morphologically structured nonwords (e.g., alarmer–ALARM), low-frequency words with a mean frequency of 2 per million (e.g., notional–NOTION), and high-frequency words with a mean frequency of 60 per million (e.g., national–NATION). These three conditions yielded significant and equivalent effects, lending strong support to the notion of a routine form of decomposition that is applied to all morphologically structured stimuli.     

Masked priming effect reflects evidence accumulated by the prime

In the same–different match task, masked priming is observed with the same responses but not different responses. Norris and Kinoshita's (2008) Bayesian reader account of masked priming explains this pattern based on the same principle as that explaining the absence of priming for nonwords in the lexical decision task. The pattern of priming follows from the way the model makes optimal decisions in the two tasks; priming does not depend on first activating the prime and then the target. An alternative explanation is in terms of a bias towards responding “same” that exactly counters the facilitatory effect of lexical access. The present study tested these two views by varying both the degree to which the prime predicts the response and the visibility of the prime. Unmasked primes produced effects expected from the view that priming is influenced by the degree to which the prime predicts the response. In contrast, with masked primes, the size of priming for the same response was completely unaffected by predictability. These results rule out response bias as an explanation of the absence of masked priming for different responses and, in turn, indicate that masked priming is not a consequence of automatic lexical access of the prime.     

Masked phonological priming effects in English: are they real? Do they matter?

For over 15 years, masked phonological priming effects have been offered as evidence that phonology plays a leading role in visual word recognition. The existence of these effects-along with their theoretical implications-has, however, been disputed. The authors present three sources of evidence relevant to an assessment of the existence and implications of these effects. First, they present an exhaustive meta-analytic literature review, in which they evaluate the strength of the evidence for masked phonological priming effects on English visual word processing. Second, they present two original experiments that demonstrate a small but significant masked priming effect on English visual lexical decision, which persists in conditions that may discourage phonological recoding. Finally, they assess the theory of visual word recognition offered by the DRC model (Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001) in the context of their empirical data. Through numerous simulations with this model, they argue that masked phonological priming effects might best be captured by a weak phonological (i.e., dual-access) theory in which lexical decisions are made on the basis of phonological information.     

Using Statistical Models of Morphology in the Search for Optimal Units of Representation in the Human Mental Lexicon

Determining optimal units of representing morphologically complex words in the mental lexicon is a central question in psycholinguistics. Here, we utilize advances in computational sciences to study human morphological processing using statistical models of morphology, particularly the unsupervised Morfessor model that works on the principle of optimization. The aim was to see what kind of model structure corresponds best to human word recognition costs for multimorphemic Finnish nouns: a model incorporating units resembling linguistically defined morphemes, a whole‐word model, or a model that seeks for an optimal balance between these two extremes. Our results showed that human word recognition was predicted best by a combination of two models: a model that decomposes words at some morpheme boundaries while keeping others unsegmented and a whole‐word model. The results support dual‐route models that assume that both decomposed and full‐form representations are utilized to optimally process complex words within the mental lexicon.