Eye movements when reading words with $YMβOL$ and NUM83R5: There is a cost

Recent evidence from masked priming experiments has revealed that readers regularize letter-like symbols and letter-like numbers into their corresponding base letters with minimal processing cost. However, one open question is whether the same pattern occurs when these items are presented during normal silent reading. In the present study, we respond to this question in an eye-movement experiment that included sentences with words that had symbols and numbers as letters, as in “YESTERDAY I SAW THE SECRE74RY WORKING VERY HARD”. Results revealed that there is a greater reading cost associated with letter-by-number replacements than with letter-by-symbol replacements, especially when the replaced letters occur at the beginning of the word. We examine the implications of these findings for models of visual word recognition and reading.     

Conscious and unconscious lexical retrieval blocking in younger and older adults

The effects of orthographically overlapping prime words in a word fragment completion task (modified from S. M. Smith & D. R. Tindell, 1997) were studied in younger and older adults. Participants studied words and then completed word fragments corresponding to those words. Fragments were preceded by a blocking, unrelated, or neutral prime. In Experiment 1, all participants were slower and less likely to complete the word fragments correctly in the blocking prime condition. Older adults also were more likely to use the blocking prime to incorrectly complete the word fragment compared with younger adults, even when warned against doing so (Experiment 2). Experiment 3 used a masked priming paradigm in younger adults to examine whether conscious processing of the prime word was necessary to produce blocking effects. Reliable blocking effects were obtained, including an intrusion rate similar to that observed in older adults in the first two experiments. These results suggest that certain aspects of word-finding failures in normal aging may be related to the reduced ability to control the activation of a lexical competitor when attempting to retrieve a target word.     

Priming word recognition with orthographic neighbors: effects of relative prime-target frequency

Four lexical decision experiments were performed with an orthographic priming paradigm in which test words were preceded by orthographically related or unrelated prime words. When prime words were presented for 350 ms without a mask, it was observed that primes that are lower frequency orthographic neighbors of the target interfered with target processing relative to an unrelated condition. When primes were higher frequency neighbors of the target, no interference or facilitation was observed. On the other hand, with briefly presented masked primes, interference was observed with higher frequency prime words. Finally, facilitatory effects in masked repetition priming were obtained with both high- and low-frequency prime-target pairs. The results are interpreted in terms of activation and selection processes operating in visual word recognition.     

Recognition time for letters and nonletters: effects of serial position, array size, and processing order

Three experiments address the question of whether end-effects (the advantage for the first and last letters in multi-letter arrays) are due to sensory or cognitive factors. The basic strategy used was to compare letters with symbol stimuli that do not lend themselves to top-down processing. Serial position functions using central fixation were obtained in the first experiment for letters, digits, and symbols. End-effects were present with both letters and digits, indicating that processes limited to word recognition cannot be responsible for end-effects. Five-symbol arrays, however, yielded U-shaped reaction time functions, with poorest performance at the initial and terminal positions. The effects of array size and retinal placement were investigated with letters and symbols in a second experiment. Multi-letter and symbol arrays differed primarily in that letters showed end-effects that were independent of retinal placement, whereas symbols did not. The conclusion that multi-letter and symbol arrays are not processed in the same way was tested in a third experiment. Using a paradigm that eliminated processing order as a variable, the experiment obtained identical effects of ordinal position within an array for letters, digits, and symbols. It is concluded that sensory factors cannot provide a viable account of letter end-effects and that letter and nonletter comparisons can improve our understanding of the sensory and cognitive factors involved in letter perception.     

Masked priming of prefixes and the influence of spelling-meaning consistency

Two experiments are reported which examined whether a prefixed word can be primed by a word sharing only the prefix letters in a masked priming paradigm. In addition the studies examined whether the size of the priming effect is influenced by the consistency with which a prefix letter pattern appears in real prefixed words. The ratio of real prefixed words to all words containing a prefix letter pattern was calculated and used to identify high-consistency prefixes, which are frequently used as prefixes (e.g., UN in UNHAPPY) and rarely appear as pseudoprefixes (e.g., UNCLE), and low-consistency prefixes, which appear in many pseudoprefixed words (e.g., DE in DESERT) but fewer truly prefixed words (e.g., DECODE). In Experiment 1, decision latencies for both types of prefixes were facilitated when real prefixed target words were preceded by real prefixed prime words in a short SOA masked priming paradigm, although the size of the priming effect for low-consistency prefixes was similar in size to that for orthographic controls. In Experiment 2, real prefixed target words were preceded by pseudoprefixed prime words. Facilitation in performance remained for high-consistency prefixes but was absent for low-consistency prefixes. These results support models of morphological processing that are sensitive to the statistical nature of the relationships between orthographic and semantic representations in a language.     

Masked transposition effects for simple versus complex nonalphanumeric objects

When two letters/digits/symbols are switched in a string (e.g., jugde–judge; 1492–1942; *?When two letters/digits/symbols are switched in a string (e.g., jugde-judge; 1492-1942; *?$&-*$?&), the resulting strings are perceptually similar to each other and produce a sizable masked transposition priming effect with the masked priming same-different matching task. However, a parallel effect does not occur for strings of pseudoletters (e.g., [letters in the text]); García-Orza, Perea, & Mu?oz, Quarterly Journal of Experimental Psychology, 63, 1603-1618, 2010). In the present study, we examined whether masked transposition priming is specific to alphanumeric stimuli or whether it also occurs with strings composed of other "objects"-namely, line drawings of common objects (Experiment 1) and geometrical shapes (Experiment 2). Results showed a significant masked transposition priming effect for geometrical shapes (e.g., [geometrical shapes in the text]), but not for line drawings of common objects (e.g., [symbols in the text]). These findings suggest that the mechanism involved in the coding of position in masked priming works only with perceptually simple, familiar "objects" (i.e., letters, numbers, symbols, or geometrical shapes), once their identities have been well ascertained.     

The effects of forced serial processing on identification of words and random letter strings

Skilled readers identified words and random letter strings displayed one letter at a time on the screen of a computer-controlled oscilloscope. Letters were either displayed in a single position, or painted left-to-right in adjacent positions. Adjacent displays were either unmasked, masked by a letter-like pattern following each letter (backward masking) or masked by a pattern preceding each letter (forward masking). Unmasked words were identified with a high degree of accuracy, and accuracy was independent of the exposure duration of the letters over the range 50–200 msec. Masked adjacent word displays and one-position word displays were identified much less accurately, and accuracy was highly dependent on letter exposure duration. In contrast to these results, identification of random strings, or of letters within random strings, was almost unaffected by the presence of the mask and was dependent on letter exposure duration under all display conditions. The results are interpreted as evidence that (a) masking forces subjects to process serial displays one letter at a time, and (b) words, or large segments of words, are habitually processed in parallel, while random strings are processed as a series of individual letters or small chunks.     

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.     

Unconscious processing of dichoptically masked words

In three experiments, the subjects' task was to decide whether each of a series of words connoted something good (e.g., fame, comedy, rescue) or bad (stress, detest, malaria). One-half second before the presentation of each such target word, an evaluatively polarized priming word was presented briefly to the nondominant eye and was masked dichoptically by either the rapidly following (Experiment 1) or simultaneous (Experiments 2 and 3) presentation of a random letter-fragment pattern to the dominant eye. (The effectiveness of the masking procedure was demonstrated by the subjects' inability to discriminate the left vs. right position of a test series of words.) In all experiments, significant masked priming effects were obtained; evaluative decisions to congruent masked prime-target combinations (such as a positive masked prime followed by a positive target) were significantly faster than those to incongruent (e.g., negative prime/positive target) or noncongruent (e.g., neutral prime/positive target) combinations. Also, in two of the three experiments, when subjects were at chance accuracy in discriminating word position, their position judgments were nevertheless significantly influenced by the irrelevant semantic content (LEFT vs. RIGHT) of the masked position-varying words. The series of experiments demonstrated that two very different tasks--speeded judgment of evaluative meaning and nonspeeded judgment of word position--yielded statistically significant and replicable influences of the semantic content of apparently undetectable words. Coupled with previous research by others using the lexical decision task, these findings converge in establishing the reliability of the empirical phenomenon of semantic processing of words that are rendered undetectable by dichoptic pattern masking.     

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.     

Masked priming effects with syllabic neighbors in a lexical decision task

Four lexical decision experiments using a masked priming paradigm were conducted to analyze whether the previous presentation of a syllabic neighbor (a word sharing the same 1st syllable) influences recognition performance. The results showed an inhibitory effect of more frequent syllabic primes and some facilitation of nonword syllabic primes (Experiments 1-3). When monosyllabic pairs were used (Experiment 3), no priming effects of the 2 initial letters were found. Finally, when using only syllables as primes, latencies to words were shorter when preceded by primes that corresponded to the 1st syllable than by primes that contained 1 letter more or less than the 1st syllable (Experiment 4). Results are interpreted using activation models that take into account a syllabic level of representation.     

Primed-lexical decision: The effect of varying the stimulus-onset asynchrony of prime and target

Lexical decisions to word targets are usually faster when they are preceded by associatively related word primes than when they follow a neutral prime. Also; it has been shown that, under certain circumstances, lexical decisions to words preceded by unassociated word primes are slower than those to words following a neutral prime. The present study explores the influence of the stimulus-onset asynchrony (SOA) of prime and target on these priming effects. Eleven SOAs were investigated ranging from 100 msec to 1240 msec. The facilitatory effect of related primes was reliable in all SOA conditions. The inhibitory effect of unrelated primes was reliable in all but one SOA condition. Furthermore, it was found that, up to the longest SOA, facilitation increases with SOA, whereas inhibition remains virtually constant. In the longest SOA condition both facilitation and inhibition decrease. Yet another finding was that pseudowords following non-neutral primes were processed faster than those preceded by neutral primes, except with the two shortest SOAs. It appears that the SOA data cannot be satisfactorily interpreted in terms of actual priming processes, that is, processes that prepare subsequent word recognition, and that some experimental artifacts may partly have been responsible for the observed pattern of results.     

Rapid processing of letters,digits and symbols: what purely visual‐attentional deficit in developmental dyslexia?

Visual‐attentional theories of dyslexia predict deficits for dyslexic children not only for the perception of letter strings but also for non‐alphanumeric symbol strings. This prediction was tested in a two‐alternative forced‐choice paradigm with letters, digits, and symbols. Children with dyslexia showed significant deficits for letter and digit strings but not for symbol strings. This finding is difficult to explain for visual‐attentional theories of dyslexia which postulate identical deficits for letters, digits and symbols. Moreover, dyslexics showed normal W‐shaped serial position functions for letter and digit strings, which suggests that their deficit is not due to an abnormally small attentional window. Finally, the size of the deficit was identical for letters and digits, which suggests that poor letter perception is not just a consequence of the lack of reading. Together then, our results show that symbols that map onto phonological codes are impaired (i.e. letters and digits), whereas symbols that do not map onto phonological codes are not impaired. This dissociation suggests that impaired symbol‐sound mapping rather than impaired visual‐attentional processing is the key to understanding dyslexia.     

Masked priming of words and nonwords in a naming task: Further evidence for a nonlexical basis for priming

Masked priming effects in word identification tasks such as lexical decision and word naming have been attributed to a lexical mechanism whereby the masked prime opens a lexical entry corresponding to the target word. Two experiments are reported in which masked repetition priming effects of similar magnitude were obtained with word and nonword targets in a naming task. Masked orthographic priming was more stable for word than for nonword targets, although morphological primes produced no advantage beyond that achieved by matched orthographic primes. These results, taken together with the recent finding that repetition priming of nonwords can be obtained in the lexical decision task, support the view that masked priming of words and nonwords has a nonlexical component. We suggest that masked primes can enhance target identification by contributing to the construction of an orthographic or a phonological representation of the target, regardless of the target's lexical status.     

The effect of preview eccentricity in a lexical decision task

We report lexical decision experiments in which eye movements and lexical decision time were analysed. The results show that nonwords produced more fixation than words, and that the time to make a lexical decision was also greater for nonwords. Further, a preview of the stimulus was presented on some occasions either at fixation or peripherally. When the presentation was peripheral the number of refixations and lexical decision times were reduced. Parafoveal previews of words also reduced word length effects on refixations and lexical decision time. These effects decreased (for nonwords) when the case of the letters was changed in the preview. These results are compatible with the idea that the peripheral preview benefit derives from word visual structure in addition to information about word length, word envelope, and single letter identities.     

Do transposed-letter similarity effects occur at a prelexical phonological level?

Nonwords created by transposing two letters (e.g., RELOVUTION) are very effective at activating the lexical representation of their base words (Perea & Lupker, 2004). In the present study, we examined whether the nature of transposed-letter (TL) similarity effects was purely orthographic or whether it could also have a phonological component. Specifically, we examined transposed-letter similarity effects for nonwords created by transposing two nonadjacent letters (e.g., relovución-REVOLUCION) in a masked form priming experiment using the lexical decision task (Experiment 1). The controls were (a) a pseudohomophone of the transposed-letter prime (relobución-REVOLUCION; note that B and V are pronounced as /b/ in Spanish) or (b) an orthographic control (relodución-REVOLUCION). Results showed a similar advantage of the TL nonword condition over the phonological and the orthographic control conditions. Experiment 2 showed a masked phonological priming effect when the letter positions in the prime were in the right order. In a third experiment, using a single-presentation lexical decision task, TL nonwords produced longer latencies than the orthographic and phonological controls, whereas there was only a small phonological effect restricted to the error data. These results suggest that TL similarity effects are orthographic--rather than phonological--in nature.     

Repetition blindness in priming in perceptual identification: Competitive effects of a word intervening between prime and target

University students named a 72-ms masked target word that was preceded by two 120-ms consecutively presented words, a prime word followed by a distractor. In Experiment 1, all words were in lowercase letters, whereas in Experiment 2, the target word was changed to uppercase letters. In both experiments there was an accuracy and latency cost (repetition blindness: RB) when the prime was the same word as the target, with the cost much less severe in Experiment 2 than in Experiment 1. A low-frequency distractor impaired target identification compared with a high-frequency distractor. Distractor frequency interacted with target frequency such that high-frequency targets preceded by low-frequency distractors had the lowest accuracy. The results are consistent with a frequency-dependent competition for access to working memory among briefly displayed words. However, there was no clear evidence that effects of target repetition on interword competition play a role in RB. The effects of a letter case change for the target are consistent with a contribution of token distinctiveness to word-order recovery in the intervening-word priming task.     

Associative and repetition priming with the repeated masked prime technique: No priming found

Wentura and Frings (2005) reported evidence of subliminal categorical priming on a lexical decision task, using a new method of visual masking in which the prime string consisted of the prime word flanked by random consonants and random letter masks alternated with the prime string on successive refresh cycles. We investigated associative and repetition priming on lexical decision, using the same method of visual masking. Three experiments failed to show any evidence of associative priming, (1) when the prime string was fixed at 10 characters (three to six flanking letters) and (2) when the number of flanking letters were reduced or absent. In all cases, prime detection was at chance level. Strong associative priming was observed with visible unmasked primes, but the addition of flanking letters restricted priming even though prime detection was still high. With repetition priming, no priming effects were found with the repeated masked technique, and prime detection was poor but just above chance levels. We conclude that with repeated masked primes, there is effective visual masking but that associative priming and repetition priming do not occur with experiment-unique prime-target pairs. Explanations for this apparent discrepancy across priming paradigms are discussed. The priming stimuli and prime-target pairs used in this study may be downloaded as supplemental materials from mc.psychonomicjournals. org/content/supplemental.     

Some linguistic determinants of Swedish word recognition

Native Swedish words and words of foreign origin were studied in a word fill-in task (Experiment 1), in a task in which words were explicitly classified as being native or loan words (Experiment 2), and in a lexical decision task in which a small onset asynchrony was introduced in displaying a word's letter pattern (Experiment 3). The findings obtained show that, both in simple printed word recognition and when asked to make explicit judgments about origin, readers are sensitive to phonological features of words not marked in Swedish orthography. It was further found that previewing a substring of word-initial letters which determines a word's root morpheme will prime recognition, whereas previewing a randomly selected pattern of letters inhibits recognition.     

Evidence for word length coding during visual word recognition

In a masked priming procedure manipulating orthographic neighbourhood size, the priming word activates a number of word candidates of which the target could be one. Whether the target is one of the candidates or not determines how quickly it is recognised. However, the efficiency of lexical processing may be markedly less if all possible candidates are activated. One solution to this problem is if the visual system uses prime length information to reduce the number of candidates to a more manageable amount. Here, we investigated in two masked priming experiments whether prime length and orthographic information combine to facilitate target word recognition. In Experiment 1, we showed that the efficiency of visual word recognition is not influenced by the length of primes alone. However, when combined with orthographically related primes, word length coding is preserved. In Experiment 2, we investigated whether length priming affects recognition of short and long words differently. Results showed that only short words benefit from a same-length orthographically related prime, and that the priming effect does not generalise to longer words. These results suggest that the length of a word is not an essential feature in lexical processing, but that it can facilitate recognition by constraining the activation of orthographically related words.