Letter detection in very familiar texts

In the present study, we investigated whether patterns of letter detection for function and content words in texts are affected by the familiarity of the material being read. In Experiment 1, subjects searched for target letters in sentences that had been rehearsed prior to performing the letter detection on them as well as on unfamiliar sentences. In Experiment 2, subjects searched for target letters in highly familiar verses (e.g., nursery rhymes) and in unfamiliar sentences that were matched to the familiar verses. A disadvantage in letter detection for function as compared with content words consistently found with unfamiliar passages was reduced significantly with the familiar material in both experiments. Specifically, letter detection for content words grew worse in familiar text, but letter detection for function words showed a contrasting modest, though nonsignificant, improvement. The results are consistent with the proposition that in very familiar texts, parafoveal analysis permits the identification of generally less familiar content words. Simultaneously, the normal pattern of weighing the structure and content elements of text changes so that more fixations on function words occur than when one is reading unfamiliar texts.     

Spelling-to-sound regularity affects pronunciation latency but not lexical decision

Summary A series of experiments are reported concerning the regularity effect in single- word pronunciation and lexical decision tasks. Experiment 1 compared pronunciation latencies for exception words based on unfamiliar letter patterns (e.g., YACHT) with exception words based on common letter patterns (e.g., PINT). It was found that both types of exceptions produced longer latencies than regular words. Experiment 2 employed a more objective basis for matching exception and regular words for letter pattern familiarity. Under these conditions exception words still produced significantly longer pronunciation latencies than regular words. These experiments show that previous demonstrations of the regularity effect in pronunciation cannot be attributed to uncontrolled visual differences between exception and regular words. Experiment 3 investigated whether the same material as Experiment 2 would produce a regularity effect in lexical decision but this was not found. Theoretical implications of these resuts and discrepancies with previous studies are discussed.     

Detection of intraword and interword letter repetition: A test of the word unitization hypothesis

Do words, as familiar units or gestalts, tend to swallow up and conceal their letter components (Pillsbury, 1897)? Letters typically are detected faster and more accurately in words than in nonwords (i.e., scrambled collections of letters), and in more frequent words than in less frequent words. However, a word advantage at encoding, where the representation of the string is formed, might compensate for, and thus mask, a word disadvantage at decoding and comparison, where the component letters of the representation are accessed and compared with the target letter. To better reveal any such word disadvantage, a task was used in this study that increased the amount of letter processing. Subjects judged whether a letter was repeated within a six-letter word or a nonword (Experiment 1; intraword letter repetition) or was repeated between two adjacent unrelated six-letter words or nonwords (Experiment 2; interword letter repetition). Contrary to Pillsbury's word unitization hypothesis, both types of letter repetition (intraword and interword) were detected faster and just as accurately with words as with nonwords. In Experiment 2, however, interword letter repetition was detected less accurately on common words (but not on rare words or third-order pseudowords) than on the corresponding nonwords. Thus, although the familiar word does not deny access to its own component letters, it does make their comparison with letters from other words more difficult.     

Syllable onsets are perceptual reading units

Syllable onsets are defined as the initial consonant or consonant cluster in a syllable (e.g., BR in BREAD). In the present study, using a letter detection paradigm and French words, we tested whether syllable onsets are processed as units by the reading system. In Experiment 1, we replicated Gross, Treiman, and Inman's (2000) result of observing no difference between the detection latencies of letters embedded in a multi-letter syllable onset (e.g., c in ECLATER) relative to a single-letter syllable onset (e.g., C in ECARTER). In Experiment 2, participants took longer to detect the target letter when it was in the second position of a multi-letter onset (e.g., L in TABLIER) than when it was a single-letter onset (e.g., L in ECOLIER). In Experiment 3, this position effect was replicated for graphemes. In Experiment 4, we tested and ruled out an alternative explanation of the unitization effect, in terms of lateral masking. These results indicate that syllable onsets are processed as perceptual units by the reading system and that the unitization effect is position dependent.     

Letter search through words and nonwords: The effect of fixed,absent, or mutilated targets

The present study attempted to eliminate the word superiority effect found in letter search by holding the target letter fixed across trials. The expectation was that the target would thereby become so familiar and salient that the subject would "see" only that letter during search. Even with the target-letter held fixed (Experiment I), however, search was still faster through words than through nonwords, indicating that nontarget letters had been "seen" as well. Search also remained faster through words than through nonwords when the number of exposures to the target was further increased by having the subject search for the absence rather than the presence of the target letter (Experiment III). In line with the notion of "proofreader's errors," however, search became relatively more accurate on nonwords than on words when it required detection of the "mutilation" produced by substituting an F for an E, e.g., BASKFT, BAKFRY (Experiment IV).     

An attention account of neural priming

Repetition priming of familiar stimuli (e.g., objects) produces a decrease in visual cortical activity for repeated versus novel items, which has been attributed to more fluent processing for repeated items. By contrast, priming of unfamiliar stimuli (e.g., abstract shapes) produces an increase in visual cortical activity. The mechanism for priming-related increases in activity for repeated unfamiliar stimuli is unknown. We hypothesised that such increases in activity may reflect attentional allocation to these items. We tested this hypothesis using a priming-spatial attention paradigm. During Phase 1 of Experiment 1, participants viewed unfamiliar abstract shapes and familiar objects. During Phase 2, participants identified target letters (S or H). Each target letter was preceded by a non-informative shape or object cue that was repeated (from Phase 1) or novel in the same (valid) or opposite (invalid) hemifield. In Experiment 2, we manipulated shape familiarity by presenting shapes once or six times during Phase 1. For both experiments, at valid locations, target identification accuracy was higher following repeated versus novel unfamiliar item cues and lower following repeated versus novel familiar item cues. These findings support our hypothesis that priming-related increases in visual cortical activity for repeated unfamiliar items may, in part, reflect attentional allocation.     

The impact of familiarization strategies on the missing-letter effect

When reading a text and searching for a target letter, readers make more omissions of the target letter if it is embedded in frequent function words than if it is in rare content words. While word frequency effects are consistently found, few studies have examined the impacts of passage familiarity on the missing-letter effect and studies that have present conflicting evidence. The present study examines the effects of passage familiarity, as well as the impacts of passage familiarization strategy promoting surface or deep encoding, on the missing-letter effect. Participants were familiarized with a passage by retyping a text, replacing all common nouns with synonyms, or generating a text on the same topic as that of the original text, and then completed a letter search task on the familiar passage as well as an unfamiliar passage. In Experiment 1, when both familiar and unfamiliar passages use the same words, results revealed fewer omissions for the retyping and synonyms conditions. However, in Experiment 2, when different words are used in both types of texts, no effect of familiarization strategy was observed. Furthermore, the missing-letter effect is maintained in all conditions, adding support to the robustness of the effect regardless of familiarity with the text.     

Eye movements when reading transposed text: the importance of word-beginning letters

Participants' eye movements were recorded as they read sentences with words containing transposed adjacent letters. Transpositions were either external (e.g., problme, rpoblem) or internal (e.g., porblem, probelm) and at either the beginning (e.g., rpoblem, porblem) or end (e.g., problme, probelm) of words. The results showed disruption for words with transposed letters compared to the normal baseline condition, and the greatest disruption was observed for word-initial transpositions. In Experiment 1, transpositions within low frequency words led to longer reading times than when letters were transposed within high frequency words. Experiment 2 demonstrated that the position of word-initial letters is most critical even when parafoveal preview of words to the right of fixation is unavailable. The findings have important implications for the roles of different letter positions in word recognition and the effects of parafoveal preview on word recognition processes.     

A test of the Sophisticated Guessing Theory of word perception

Under difficult viewing conditions, a letter in a familiar word can be perceived more accurately than the same letter alone or in a string of unrelated letters. Sophisticated Guessing Theory asserts that perception is more accurate when a letter appears in a word because its identity is constrained by the identity of neighboring context letters. Experiment 1 tested the following prediction: A letter in a word should be perceived more accurately in strongly constraining word contexts than in weakly constraining word contexts. No such trend was found using a number of different measures of contextual constraint and perceptual accuracy. Experiment 2 verified that, with the same conditions used in Experiment 1 to test Sophisticated Guessing Theory, a strong perceptual advantage could be obtained for letters in words vs. letters alone or in unrelated-letter strings. Several alternative theories of word perception are discussed. The most attractive asserts that for words an additional higher-level perceptual code is formed that is more resistant to degradation than the code formed for letters.     

Children's Production of Unfamiliar Word Sequences Is Predicted by Positional Variability and Latent Classes in a Large Sample of Child-Directed Speech

We explore whether children's willingness to produce unfamiliar sequences of words reflects their experience with similar lexical patterns. We asked children to repeat unfamiliar sequences that were identical to familiar phrases (e.g., A piece of toast) but for one word (e.g., a novel instantiation of A piece of X, like A piece of brick). We explore two predictions-motivated by findings in the statistical learning literature-that children are likely to have detected an opportunity to substitute alternative words into the final position of a four-word sequence if (a) it is difficult to predict the fourth word given the first three words and (b) the words observed in the final position are distributionally similar. Twenty-eight 2-year-olds and thirty-one 3-year-olds were significantly more likely to correctly repeat unfamiliar variants of patterns for which these properties held. The results illustrate how children's developing language is shaped by linguistic experience.     

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.     

Why is word recognition impaired by disorientation while the identification of single letters is not?

Past research has shown that speed of identifying single letters or digits is largely indifferent to orientation, whereas the recognition of single words or connected text is markedly disrupted by disorientation. In a series of four experiments, we attempted to reconcile these findings. The results suggest that disorientation does not impair the identification of the characters but disrupts the perception of their spatial arrangement. When spatial order information is critical for distinguishing between different stimuli, disorientation is disruptive because some rectification process is required to restore order information. Utilizing the similarity between the letter B and the number 13, we found strong effects of orientation when a stimulus was interpreted as the two-digit number 13 but not when interpreted as the single letter B. This, however, occurred only when the set of numbers to be classified included permutations of the same digits (Experiments 1 and 2). Odd-even decisions on single-digit and two-digit numbers (Experiment 3) yielded strong effects of stimulus orientation for order-dependent numbers (e.g., 32), weaker effects for order-independent numbers (e.g., 24), and none for repeated-digit (e.g., 22) or single-digit numbers. Classification time for two-letter Hebrew words evidenced strong effects of orientation for words that differed only in letter order but much weaker effects for words that had no letters in common, even when these were embedded within some words that did (Experiment 4).     

The word-superiority effect and phonological recoding

Previous work indicates that the locus of the word-superiority effect in letter detection is nonvisual and that letter names, but not letter shapes, are more accessible in words than in nonwords, that is, scrambled collections of letters (e.g., Krueger & Shapiro, 1979; Krueger & Stadtlander, 1991; Massaro, 1979). The nonvisual (verbal or lexical) coding may be phonological, or it may be more abstract. In the present study, a word advantage in the speed of letter detection was found even when the target letter was silent in the six-letter test word (e.g., s in island). Other test words varied in their frequency of occurrence in English and number of syllables (1, 2, or 3). The word advantage was larger for higher frequency words but was not affected by syllable length. The presence of unpronounceable nonwords and silent letters in the words discouraged reliance upon the phonological code but did not thereby eliminate the word advantage. Thus, the word-superiority effect with free viewing is not based entirely upon phonological recoding.     

Object and action picture naming in English and Greek

When two orthographically similar words are displayed using rapid serial visual presentation (RSVP), the repeated letters in the second critical word (W2) are not detected, leading to a deficit in reporting this word known as repetition blindness (RB). In Turkish, letters containing diacritic markings (e.g., y, ö) are considered separate letters, yet are visually highly similar to their non-diacritic analogues (s,o). Two experiments used the phenomenon of RB to investigate whether diacritic letters are represented as more similar to their non-diacritic analogues than are two unrelated letters. In Experiment 1, substantially more RB was found for words differing in just a diacritic (i y im-isim) compared to orthographic neighbours (words differing in a visually non-similar letter, such as ilim-isim). In Experiment 2, the amount of RB for identical words (isim-isim) was comparable to words that differed by a single diacritic marking (i y im-isim). We conclude that diacritic letters are mentally represented as variants of their non-diacritic analogue. Letter / word recognition researchers may be interested in pursuing these findings using standard techniques such as backward masking and orthographic priming.     

Familiarity affects visual processing of words.

While previous research has demonstrated that words can be processed more rapidly and/or more accurately than random strings of letters, it has not been convincingly demonstrated that the superior processing of words is a visual effect. In the present experiment, the cases of letters were manipulated in letter strings that were to be compared on the basis of physical identity. Mean response time was shorter for words than for nonwords even for pairs of letter strings that differed only in case (e.g., site-site). This finding implies that the advantage of words over nonwords (the familiarity effect) typically observed in the simultaneous matching task is not due solely to comparison of either the word names or the letter names and, thus, that at least part of the familiarity effect must be due to more rapid formation and/or comparison of visual representations of the two letter strings when they are words. Further analysis failed to reveal a significant involvement of phonemic or lexical codes in the comparison judgments.     

Contextual control of letter perception

This study examined the hypothesis that the type of list context in which a given item is embedded may affect the way in which it is perceptually processed. In the first experiment, subjects matched four types of test items inserted in four types of lists. The types of test items and the types of lists in which they were embedded were two-letter words, two-letter spelling clusters, unrelated letter pairs, and pairs of novel letters. The first experiment indicated that only unrelated letter pairs were significantly affected by type of list in which they were inserted. The pattern of the effect was confirmed in the latency data of the second experiment and the interpretation was that only unrelated letter and related letter-group contexts were operating in the first two experiments. The third and fourth experiments were concerned with contrasting contexts at the feature and letter levels of processing. By using lists in which type of catch trial either emphasized local features or global aspects of a pattern, the processing times of both familiar and unfamiliar letters were affected. The results of these experiments suggest that information processing models should incorporate structures which represent the way that context selectively facilitates processing of items at particular levels.     

Direct assessments of the processing time hypothesis for the missing-letter effect

When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequently used words or in the most frequent meaning of a polysemic word. According to the processing time hypothesis, this occurs because familiar words and meanings are identified faster, leaving less time for letter identification. Contrary to the predictions of the processing time hypothesis, with a rapid serial visual presentation procedure, participants were slower at detecting target letters for more frequent words or the most frequent meaning of a word (Experiments 1 and 2) or at detecting the word itself instead of a target letter (Experiment 3). In Experiments 4 and 5, participants self-initiated the presentation of each word, and the same pattern of results was observed as in Experiments 1 and 3. Positive correlations were also found between omission rate and response latencies.     

Effect of direction of sequential presentation and redundancy on short-term recognition memory

Short-term recognition memory was tested by presenting six letters, one after the other, followed by a target letter and having S indicate whether or not the target matched one of the six letters. Recognition memory for a letter was better when it was embedded in a six-letter word, rather than a nonword, and when it was included in a sequence presented left-to-right, rather than right-to-left (Experiment 1). Reducing the presentation rate from 4/sec to 2.5/sec largely eliminated the left-to-right effect (Experiment 2). The effect of direction of presentation was greater for redundant (Experiment 1) than for nonredundant sequences (Experiment 3) and was greater for Ss who more frequently formed a word out of the sequence (Experiments 1 and 2), but was no greater for words than nonwords (Experiments 1 and 2) and no greater for letter than for line-figure sequences (Experiment 3). These findings suggest that the left-to-right effect depends as much, or more, on “peripheral” processes (e.g., eye movements) as on “central” processes (e.g., reading).     

Detecting phonemes and letters in text: Interactions between different types and levels of processes

In six experiments, subjects detected phonemes or letters in text presented auditorily or visually. Experiments 1 and 2 provided support for the hypothesis that a mismatch between the phoneme and letter representations of a target leads to detection errors. In addition, visual word unitization processes were implicated. Experiments 3 and 4 provided support for the hypothesis that the Gestalt goodness of pattern affected detection errors when subjects searched for letters. Experiments 5 and 6 demonstrated that the effects of unitization on the detection of letters in common words were decreased by altering the familiar configuration of the test words. The combined results of all six experiments lead to the conclusion that both visual and phonetic processes influence letter detection, that these processes communicate through a type of cross-checking, and that there are at least two levels of visual (and perhaps of phonetic) processing involved in the letter detection task.     

Phonological Activation in Multi-syllabic Sord Recognition

Three experiments were conducted to test the phonological recoding hypothesis in visual word recognition. Most studies on this issue have been conducted using mono-syllabic words, eventually constructing various models of phonological processing. Yet in many languages including English, the majority of words are multi-syllabic words. English includes words incorporating a silent letter in their letter strings (e.g., champane). Such words provide an opportunity for investigating the role of phonological information in multi-syllabic words by comparing them to words that do not have the silent letter in the corresponding position (e.g., passener). The performance focus is on the effects of removing letters from words with a silent letter and from words with a non-silent letter. Three representative lexical tasks—naming, semantic categorization, lexical decision—were conducted in the present study. Stimuli that excluded a silent letter (e.g., champa_ne) were processed faster than those that excluded a sounding letter (e.g., passen_er) in the naming (Experiment 1), the semantic categorization (Experiment 2), and the lexical decision task (Experiment 3). The convergent evidence from these three experiments provides seminal proof of phonological recoding in multi-syllabic word recognition. An erratum to this article can be found at