What Do Letter Migration Errors Reveal About Letter Position Coding in Visual Word Recognition?

Dividing attention across multiple words occasionally results in misidentifications whereby letters apparently migrate between words. Previous studies have found that letter migrations preserve within-word letter position, which has been interpreted as support for position-specific letter coding. To investigate this issue, the authors used word pairs like STEP and SOAP, in which a letter in 1 word could migrate to an adjacent letter in another word to form an illusory word (STOP). Three experiments show that both same-position and adjacent-position letter migrations can occur, as well as migrations that cross 2 letter positions. These results argue against position-specific letter coding schemes used in many computational models of reading, and they provide support for coding schemes based on relative rather than absolute letter position. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An Observation on the Role of Context Variability in Free Recall.

The authors conducted 3 experiments investigating the effect of context variability and word frequency on free recall. Context variability refers to the number of preexperimental contexts in which a given word is experienced. Both between-subjects and within-subjects manipulations of context variability demonstrated a distinct advantage for low context variability words. Standard word frequency effects were obtained in 2 of the 3 experiments, but the common finding of no word frequency differences in mixed lists of high and low word frequency may depend on the level (low vs. high) of context variability. The authors speculate that the advantage for low context variability items may accrue from better item-to-list context associations or better storage of contextual information as a consequence of the smaller preexperimental contextual fan that these items possess. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Eye Movements and Word Skipping During Reading Revisited.

The authors examined word skipping in reading in 2 experiments. In Experiment 1, skipping rates were higher for a preview of a predictable word than for a visually similar nonword, indicating there is full recognition in parafoveal vision. In Experiment 2, foveal load was manipulated by varying the frequency of the word preceding either a 3-letter target word or a misspelled preview. There was again a higher skipping rate for a correct preview and a lower skipping rate when there was a high foveal load, but there was no interaction, and the pattern of effects in fixation times was the same as in the skipping data. Experiment 2 also showed significant skipping of nonwords similar to the target word, indicating skipping based on partial information. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Interpretation of Orthographic Uniqueness Point Effects in Visual Word Recognition.

The orthographic uniqueness point (OUP) of a word is the position of the first letter from the left that distinguishes a word from all other words. In 2 recent studies (P. J. Kwantes & D. J. K. Mewhort, 1999a; A. K. Lindell, M. E. R. Nicholls, & A. E. Castles, 2003), it has been observed that words with an early OUP were processed more quickly than words with a late OUP. This has been taken to suggest that observers process the letters of words sequentially in a left-to-right order. In this article, it is shown that the OUP results do not provide selective evidence for left-to-right sequential processing in visual word recognition because the data are also compatible with an account in which letter processing occurs in random order. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word recognition and identification: Do word-frequency effects reflect lexical access?

Tested the assumption that word-frequency effects on recognition result from differential ease of access to lexical entries for high- and low-frequency words. Previous researchers (McCann & Besner, 1987) found that pseudohomophones (e.g., TRAX) were named faster and more accurately than controls (e.g., PRAX), but pseudohomophone performance was not sensitive to base word frequency. In Exp 1 of the present series, performance on the same set of pseudohomophones and controls was assessed in the context of the lexical decision task (does this letter string spell a word?). Pseudohomophone performance was impaired relative to controls, which is commonly taken as evidence of contact with entries in a phonological lexicon. As in the naming task, however, pseudohomophone performance was insensitive to base word frequency. In Exp 2, pseudohomophone performance was examined in the context of a phonological lexical decision task (does this letter string sound like an English word?). Pseudohomophone performance was sensitive to base word frequency in phonological lexical decision. Word-frequency effects in binary decision tasks such as lexical decision and phonological lexical decision are attributed to a familiarity discriminatiion process that contributes bias to the decision stage. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Neighbourhood Density, Word Frequency, and Spelling-Sound Regularity Effects in Naming: Similarities and Differences Between Skilled Readers and the Dual Route Cascaded Computational Model.

An experiment with skilled readers and a series of simulations with the Dual Route Cascaded model (Coltheart, Rastle, Perry, Langdon, & Ziegler, 2001) investigated the joint effects of stimulus quality and Neighbourhood Density (N) in nonword naming. Neighbourhood Density and stimulus quality yielded additive effects on reaction time (RT) for skilled readers whereas the model produced an interaction between these factors. A further set of simulations show that DRC also produces an interaction between stimulus quality and (1) word frequency, (2) spelling-sound regularity, and, (3) nonword letter length. None of these three factors interact with stimulus quality in performance by skilled readers. It is suggested that DRC's assumption of cascaded processing throughout represents a central problem. A proposal as to how the model can be modified to accommodate these and other problematic data is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Eye movements and word skipping during reading: Effects of word length and predictability.

Eye movements were monitored as subjects read sentences containing high- or low-predictable target words. The extent to which target words were predictable from prior context was varied: Half of the target words were predictable, and the other half were unpredictable. In addition, the length of the target word varied: The target words were short (4–6 letters), medium (7–9 letters), or long (10–12 letters). Length and predictability both yielded strong effects on the probability of skipping the target words and on the amount of time readers fixated the target words (when they were not skipped). However, there was no interaction in any of the measures examined for either skipping or fixation time. The results demonstrate that word predictability (due to contextual constraint) and word length have strong and independent influences on word skipping and fixation durations. Furthermore, because the long words extended beyond the word identification span, the data indicate that skipping can occur on the basis of partial information in relation to word identity. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Reading aloud: Qualitative differences in the relation between stimulus quality and word frequency as a function of context.

Virtually all theories of visual word recognition assume (typically implicitly) that when a pathway is used, processing within that pathway always unfolds in the same way. This view is challenged by the observation that simple variations in list composition are associated with qualitative changes in performance. The present experiments demonstrate that when reading aloud, the joint effects of stimulus quality and word frequency on response time are driven by the presence/absence of nonwords in the list. Interacting effects of these factors are seen when only words appear in the experiment, whereas additive effects are seen when words and nonwords are randomly intermixed. One way to explain these and other data appeals to the distinction between cascaded processing (or interactive activation) on the one hand versus a thresholded mode of processing on the other, with contextual factors determining which mode of processing dominates. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word recognition and syntactic attachment in reading: Evidence for a staged architecture.

In 3 experiments, the author examined how readers' eye movements are influenced by joint manipulations of a word's frequency and the syntactic fit of the word in its context. In the critical conditions of the first 2 experiments, a high- or low-frequency verb was used to disambiguate a garden-path sentence, while in the last experiment, a high- or low-frequency verb constituted a phrase structure violation. The frequency manipulation always influenced the early eye movement measures of first-fixation duration and gaze duration. The context manipulation had a delayed effect in Experiment 1, influencing only the probability of a regressive eye movement from later in the sentence. However, the context manipulation influenced the same early eye movement measures as the frequency effect in Experiments 2 and 3, though there was no statistical interaction between the effects of these variables. The context manipulation also influenced the probability of a regressive eye movement from the verb, though the frequency manipulation did not. These results are shown to confirm predictions emerging from the serial, staged architecture for lexical and integrative processing of the E–Z Reader 10 model of eye movement control in reading (Reichle, Warren, & McConnell, 2009). It is argued, more generally, that the results provide an important constraint on how the relationship between visual word recognition and syntactic attachment is treated in processing models. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Visual Word Recognition of Single-Syllable Words.

Speeded visual word naming and lexical decision performance are reported for 2,428 words for young adults and healthy older adults. Hierarchical regression techniques were used to investigate the unique predictive variance of phonological features in the onsets, lexical variables (e.g., measures of consistency, frequency, familiarity, neighborhood size, and length), and semantic variables (e.g.. imageahility and semantic connectivity). The influence of most variables was highly task dependent, with the results shedding light on recent empirical controversies in the available word recognition literature. Semantic-level variables accounted for unique variance in both speeded naming and lexical decision performance, level with the latter task producing the largest semantic-level effects. Discussion focuses on the utility of large-scale regression studies in providing a complementary approach to the standard factorial designs to investigate visual word recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The relative position priming effect depends on whether letters are vowels or consonants.

The relative position priming effect is a type of subset priming in which target word recognition is facilitated as a consequence of priming the word with some of its letters, maintaining their relative position (e.g., csn as a prime for casino). Five experiments were conducted to test whether vowel-only and consonant-only subset primes contribute equally to this effect. Experiment 1 revealed that this subset priming effect emerged when primes were composed exclusively of consonants, compared with vowel-only primes (csn-casino vs. aia-animal). Experiment 2 tested the impact of letter frequency in this asymmetry. Subset priming effects were obtained for both high- and low-frequency consonants but not for vowels, which rules out a letter frequency explanation. Experiment 3 tested the role of phonology and its contribution to the priming effects observed, by decreasing the prime duration. The results showed virtually the same effects as in the previous experiments. Finally, Experiments 4 and 5 explored the influence of repeated letters in the primes on the magnitude of the priming effects obtained for consonant and vowel subset primes (iuo-dibujo and aea-madera vs. mgn-imagen and rtr-frutero). Again, the results confirmed the priming asymmetry. We propose that a functional distinction between consonants and vowels, mainly based on the lexical constraints imposed by each of these types of letters, might provide an explanation for the whole set of results. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Transposed-letter effects in reading: Evidence from eye movements and parafoveal preview.

Three eye movement experiments were conducted to examine the role of letter identity and letter position during reading. Before fixating on a target word within each sentence, readers were provided with a parafoveal preview that differed in the amount of useful letter identity and letter position information it provided. In Experiments 1 and 2, previews fell into 1 of 5 conditions: (a) identical to the target word, (b) a transposition of 2 internal letters, (c) a substitution of 2 internal letters, (d) a transposition of the 2 final letters, or (e) a substitution of the 2 final letters. In Experiment 3, the authors used a further set of conditions to explore the importance of external letter positions. The findings extend previous work and demonstrate that transposed-letter effects exist in silent reading. These experiments also indicate that letter identity information can be extracted from the parafovea outside of absolute letter position from the first 5 letters of the word to the right of fixation. Finally, the results support the notion that exterior letters play important roles in visual word recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Previewing the neighborhood: The role of orthographic neighbors as parafoveal previews in reading.

In 2 experiments, a boundary technique was used with parafoveal previews that were identical to a target (e.g., sleet), a word orthographic neighbor (sweet), or an orthographically matched nonword (speet). In Experiment 1, low-frequency words in orthographic pairs were targets, and high-frequency words were previews. In Experiment 2, the roles were reversed. In Experiment 1, neighbor words provided as much preview benefit as identical words and greater benefit than nonwords, whereas in Experiment 2, neighbor words provided no greater preview benefit than nonwords. These results indicate that the frequency of a preview influences the extraction of letter information without setting up appreciable competition between previews and targets. This is consistent with a model of word recognition in which early stages largely depend on excitation of letter information, and competition between lexical candidates becomes important only in later stages. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

In search of perceptual influences of sentence context on word recognition.

A major issue in the study of word perception concerns the nature (perceptual or nonperceptual) of sentence context effects. The authors compared effects of legal, word replacement, nonword replacement, and transposed contexts on target word performance using the Reicher-Wheeler task to suppress nonperceptual influences of contextual and lexical constraint. Experiment 1 showed superior target word performance for legal (e.g., "it began to flap/flop") over all other contexts and for transposed over word replacement and nonword replacement contexts. Experiment 2 replicated these findings with higher constraint contexts (e.g., "the cellar is dark/dank") and Experiment 3 showed that strong constraint contexts improved performance for congruent (e.g., "born to be wild") but not incongruent (e.g., mild) target words. These findings support the view that the very perception of words can be enhanced when words are presented in legal sentence contexts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

On the additive effects of stimulus quality and word frequency in lexical decision: Evidence for opposing interactive influences revealed by RT distributional analyses.

The joint effects of stimulus quality and word frequency in lexical decision were examined in 4 experiments as a function of nonword type (legal nonwords, e.g., BRONE, vs. pseudohomophones, e.g., BRANE). When familiarity was a viable dimension for word-nonword discrimination, as when legal nonwords were used, additive effects of stimulus quality and word frequency were observed in both means and distributional characteristics of the response-time distributions. In contrast, when the utility of familiarity was undermined by using pseudohomophones, additivity was observed in the means but not in distributional characteristics. Specifically, opposing interactive effects in the underlying distribution were observed, producing apparent additivity in means. These findings are consistent with the suggestion that, when familiarity is deemphasized in lexical decision, cascaded processing between letter and word levels is in play, whereas, when familiarity is a viable dimension for word-nonword discrimination, processing is discrete. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Word frequency or motivation in perceptual defense.

The alternative hypotheses proposed to account for differential perceptual threshold of words, (1) motivation and meaning factors, and (2) word frequency and structure factors, are tested by measuring the recognition thresholds of words having two meanings, neutral and threat. The test material consisted of a series of booklets containing thirty successive carbon copies of the test words each, the least clear copy first and the clearest last. For the experiment proper, the threat words were imbedded in a threat context, the neutral words in a neutral context. The threat group needed significantly fewer trials than the neutral group to decipher the critical words. The author concludes that, all else held constant, word meaning and motivational factors are important determinants in perceptual behavior. 23 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Frequency and neighborhood effects on lexical access: Activation or search?

Four experiments investigated the conjoint effects of word frequency and neighborhood size on performance in lexical decision, word naming, and delayed naming tasks. Neighborhood size refers to the number of words that can be created by changing one letter of a target word. Facilitatory effects of neighborhood size were observed for low- but not high-frequency effect in the lexical decision as compared with the naming task. This effect was influenced by the nature of the nonwords that had to be discriminated from words and therefore appeared to reflect the processes involved in the decision component of the lexical classification task. Overall, the results demonstrate that neighborhood size influences the lexical access process. The facilitatory nature of the neighborhood effect and its interaction with frequency provide strong support for the view that lexical access relies on an activation mechanism that is sensitive to word frequency. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Limiting lexical activation limits perceptual priming in masked word identification

Four experiments tested the hypothesis that perceptual priming of a word depends on the prior lexical processing of the word (Rajaram & Roediger, 1993; Weldon, 1991). Experiment 1 showed that first-letter naming reduced priming relative to reading a whole word on two tests: word fragment completion and masked word identification. In Experiment 2, naming the first letter of a word took longer than naming the letter presented alone, and led to better masked word identification. Experiment 3 showed that masked word identification was enhanced by prior word processing more for low frequency words than for high frequency words, but only when words had been read aloud. Experiment 4 tested whether the auditory input accruing from reading a word aloud was the source of facilitation and frequency effects. Participants judged either the frequency of the whole display or the positional frequency of the first letter in the display, and indicated their decisions manually. The major findings from Experiment 3 were replicated, ruling out the cross-modal source of those effects. It was concluded that activation of a lexical unit, one component of word processing (Vriezen, Moscovitch, & Bellos, 1995), is a critical determinant of the perceptual priming of that word.     

Effects of alphabet-letter instruction on young children's word recognition.

This study examined the influence of letter-name instruction on beginning word recognition. Thirty-three preschool children from low-socioeconomic-status families participated in 16 weeks of letter-name or comprehension-focused instruction. After instruction, children's ability to learn 3 types of word spellings was examined: words phonetically spelled with letters children had been taught (e.g., BL for ball), words phonetically spelled with letters children had not been taught, and words with visually distinct letter spellings that were nonphonetic. Children who received letter-name instruction learned words phonetically spelled with letters included in instruction significantly better than other words. Children receiving comprehension instruction performed significantly better on visually distinct word spellings. Results demonstrate the beneficial effects of alphabet-letter instruction on beginning phonetic word recognition. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

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