The effects of "neighborhood size" in reading and lexical decision.

The effects of neighborhood size ("N")--the number of words differing from a target word by exactly 1 letter (i.e., "neighbors")--on word identification was assessed in 3 experiments. In Experiments 1 and 2, the frequency of the highest frequency neighbor was equated, and N had opposite effects in lexical decision and reading. In Experiment 1, a larger N facilitated lexical decision judgments, whereas in Experiment 2, a larger N had an inhibitory effect on reading sentences that contained the words of Experiment 1. Moreover, a significant inhibitory effect in Experiment 2 that was due to a larger N appeared on gaze duration on the target word, and there was no hint of facilitation on the measures of reading that tap the earliest processing of a word. In Experiment 3, the number of higher frequency neighbors was equated for the high-N and low-N words, and a larger N caused target words to be skipped significantly more and produced inhibitory effects later in reading, some of which were plausibly due to misidentification of the target word when skipped. Regression analyses indicated that, in reading, increasing the number of higher frequency neighbors had a clear inhibitory effect on word identification and that increasing the number of lower frequency neighbors may have a weak facilitative effect on word identification.     

The spread of the phonological neighborhood influences spoken word recognition

In three experiments, the processing of words that had the same overall number of neighbors but varied in the spread of the neighborhood (i.e., the number of individual phonemes that could be changed to form real words) was examined. In an auditory lexical decision task, a naming task, and a same-different task, words in which changes at only two phoneme positions formed neighbors were responded to more quickly than words in which changes at all three phoneme positions formed neighbors. Additional analyses ruled out an account based on the computationally derived uniqueness points of the words. Although previous studies (e.g., Luce & Pisoni, 1998) have shown that the number of phonological neighbors influences spoken word recognition, the present results show that the nature of the relationship of the neighbors to the target word--as measured by the spread of the neighborhood--also influences spoken word recognition. The implications of this result for models of spoken word recognition are discussed.     

The sound of enemies and friends in the neighborhood

Previous studies (e.g., Pecher, Zeelenberg, & Wagenmakers, 2005) found that semantic classification performance is better for target words with orthographic neighbors that are mostly from the same semantic class (e.g., living) compared to target words with orthographic neighbors that are mostly from the opposite semantic class (e.g., nonliving). In the present study we investigated the contribution of phonology to orthographic neighborhood effects by comparing effects of phonologically congruent orthographic neighbors (book-hook) to phonologically incongruent orthographic neighbors (sand-wand). The prior presentation of a semantically congruent word produced larger effects on subsequent animacy decisions when the previously presented word was a phonologically congruent neighbor than when it was a phonologically incongruent neighbor. In a second experiment, performance differences between target words with versus without semantically congruent orthographic neighbors were larger if the orthographic neighbors were also phonologically congruent. These results support models of visual word recognition that assume an important role for phonology in cascaded access to meaning.     

Associative priming effects with visible, transposed-letter nonwords: JUGDE facilitates COURT

Associative priming effects can be obtained with masked nonword primes or with masked pseudohomophone primes (e.g., judpe?CCOURT, tode?CFROG), but not with visible primes. The usual explanation is that when the prime is visible, these stimuli no longer activate the semantic representations of their base words. Given the important role of transposed-letter stimuli (e.g., jugde) in visual word recognition, here we examined whether or not an associative priming effect could be obtained with visible transposed-letter nonword primes (e.g., jugde?CCOURT) in a series of lexical decision experiments. Results showed a sizable associative priming effect with visible transposed-letter nonword primes (i.e., jugde?CCOURT faster than neevr?CCOURT) in Experiments 1?C3 that was close to that with word primes. In contrast, we failed to find a parallel effect with replacement-letter nonword primes (Experiment 2). These findings pose some constraints to models of visual word recognition.     

Do transposed-letter similarity effects occur at a morpheme level? Evidence for morpho-orthographic decomposition

When does morphological decomposition occur in visual word recognition? An increasing body of evidence suggests the presence of early morphological processing. The present work investigates this issue via an orthographic similarity manipulation. Three masked priming lexical decision experiments were conducted to examine the transposed-letter similarity effect (e.g., jugde facilitates JUDGE more than the control jupbe) in polymorphemic and monomorphemic words. If morphological decomposition occurs at early stages of visual word recognition, we would expect an interaction with transposed-letter effects. Experiment 1 was carried out in Basque, which is an agglutinative language. The nonword primes were created by transposing two letters that either crossed the morphological boundaries of suffixes or did not. Results showed a transposed-letter effect for non-affixed words, whereas there were no signs of a transposed-letter effect across morpheme boundaries for affixed words. In Experiment 2, this issue was revisited in a non-agglutinative language (Spanish), with prefixed and suffixed word pairs. Again, results showed a significant transposed-letter effect for non-affixed words, whereas there were no signs of a transposed-letter effect across morpheme boundaries for affixed words (both prefixed words and suffixed words). Experiment 3 replicated the previous findings, and also revealed that, for polymorphemic words, transposed-letter priming effects occurred for within-morpheme transpositions. Taken together, these findings support the view that morphological decomposition operates at an early stage of visual word recognition.     

The neighborhood distribution effect in visual word recognition: words with single and twin neighbors

Lexical-decision tasks were used to test the role of neighborhood distribution in visual word recognition. Predictions based on the interactive activation model were generated by running simulations. The data were compared for words with 2 higher frequency neighbors that differed in their neighborhood distribution. The neighbors were "single" when they did not share a neighborhood relationship (e.g., neighbors of flanc: flanc-blanc) or "twin" when they shared a neighborhood relationship (e.g., neighbors of firme: ferme-forme). Results show a facilitatory neighborhood distribution effect on words in Experiments 1 (easy pseudowords) and 3 (difficult pseudowords and easy pseudowords) and on pseudowords in Experiment 2. These data can be accounted for in terms of lexical inhibition in the interactive activation framework.     

Transposed-letter similarity effects in naming pseudowords: Evidence from children and adults

There is growing empirical evidence that shows that transposed-letter pseudowords (e.g., relovution) are perceptually very similar to their base words. This is a finding that has important implications for the choice of an input coding scheme in visual word recognition and naming. In the present experiment, we examined the presence of transposed-letter effects for pseudowords by using the naming task in a transparent orthography (Spanish): The pseudowords were created by transposing two letters or by replacing two letters (e.g., relovución vs. retosución). Since it has been suggested that transposed-letter effects may be greater for developing than for adult readers (Castles, Davis, & Forster, 2003), we recruited beginning readers (second graders, i.e., 7-year-olds), intermediate readers (fourth graders, i.e., 9-year-olds), and adult readers (college students). Results showed that developing and adult readers frequently mispronounced transposed-letter pseudowords (lexicalisations, mostly). Interestingly, the difference between the transposed-letter pseudowords and the replacement-letter pseudowords vanished when measuring the correct naming times. We examine the implications of these findings for models of visual word recognition and naming.     

There is no clam with coats in the calm coast: Delimiting the transposed-letter priming effect

In this article, we explore the transposed-letter priming effect (e.g., jugde–JUDGE vs. jupte–JUDGE), a phenomenon that taps into some key issues on how the brain encodes letter positions and has favoured the creation of new input coding schemes. However, almost all the empirical evidence from transposed-letter priming experiments comes from nonword primes (e.g., jugde–JUDGE). Indeed, previous evidence when using word–word pairs (e.g., causal–CASUAL) is not conclusive. Here, we conducted five masked priming lexical decision experiments that examined the relationship between pairs of real words that differed only in the transposition of two of their letters (e.g., CASUAL vs. CAUSAL). Results showed that, unlike transposed-letter nonwords, transposed-letter words do not seem to affect the identification time of their transposed-letter mates. Thus, prime lexicality is a key factor that modulates the magnitude of transposed-letter priming effects. These results are interpreted under the assumption of the existence of lateral inhibition processes occurring within the lexical level—which cancels out any orthographic facilitation due to the overlapping letters. We examine the implications of these findings for models of visual-word recognition.     

More words in the neighborhood: Interference in lexical decision due to deletion neighbors

This article reports two lexical decision experiments that provide evidence for the automatic activation of deletion neighbors—that is, words that overlap with the presented word save for the deletion of one letter. Experiment 1 showed slower and less accurateno decisions for nonwords with deletion neighbors (e.g.,come inscome), relative to control nonwords. Experiment 2 showed slower and less accurate yes decisions for words with higher frequency deletion neighbors, relative to control words. An important methodological implication of these results is that stimuli should be equated using a different definition of orthographic neighborhood from that which is currently the norm. The results also have significant theoretical implications for input coding schemes and the mechanisms underlying recognition of familiar words.     

Is there a neighborhood frequency effect in English? Evidence from reading and lexical decision

What is the effect of a word's higher frequency neighbors on its identification time? According to activation-based models of word identification (J. Grainger & A. M. Jacobs, 1996; J. L. McClelland & D. E. Rumelhart, 1981), words with higher frequency neighbors will be processed more slowly than words without higher frequency neighbors because of the lexical competition mechanism embodied in these models. Although a critical prediction of these models, this inhibitory neighborhood frequency effect has been elusive in studies that have used English stimuli. In the present experiments, the effect of higher frequency neighbors was examined in the lexical decision task and when participants were reading sentences while their eye movements were monitored. Results suggest that higher frequency neighbors have little, if any, effect on the identification of English words. The implications for activation-based models of word identification are discussed.     

Parafoveal processing of transposed-letter words and nonwords: evidence against parafoveal lexical activation

The current experiments explored the parafoveal processing of transposed-letter (TL) neighbors by using an eye-movement-contingent boundary change paradigm. In Experiment 1 readers received a parafoveal preview of a target word (e.g., calm) that was either (1) identical to the target word (calm), (2) a TL-neighbor (clam), or (3) a substituted-letter (SL) nonword (chem). In Experiment 2 a further set of parafoveal preview conditions was explored including (4) an SL-word condition (chum) and (5) a TL-nonword condition (caml). Across both experiments, readers' fixation durations on the target words were significantly longer when the previews were SL previews than when they were TL neighbors, suggesting that TL neighbors (when presented in the parafovea) facilitate processing rather than inhibit processing. Experiments 3 and 4 showed that this is in contrast to the inhibitory effects that are seen when TL neighbor previews appear in the fovea.     

Phonographic neighbors,not orthographic neighbors,determine word naming latencies

The orthographic neighborhood size (N) of a word—the number of words that can be formed from that word by replacing one letter with another in its place—has been found to have facilitatory effects in word naming. The orthographic neighborhood hypothesis attributes this facilitation to interactive effects. A phonographic neighborhood hypothesis, in contrast, attributes the effect to lexical print-sound conversion. According to the phonographic neighborhood hypothesis, phonographic neighbors (words differing in one letter and one phoneme, e.g., stove and stone) should facilitate naming, and other orthographic neighbors (e.g., stove and shove) should not. The predictions of these two hypotheses are tested. Unique facilitatory phonographic N effects were found in four sets of word naming mega-study data, along with an absence of facilitatory orthographic N effects. These results implicate print-sound conversion—based on consistent phonology—in neighborhood effects rather than word-letter feedback.     

Pathway control in visual word processing: Converging evidence from recognition memory

The extent to which readers can exert strategic control over oral reading processes is a matter of debate. According to the pathway control hypothesis, the relative contributions of the lexical and nonlexical pathways can be modulated by the characteristics of the context stimuli being read, but an alternative time criterion model is also a viable explanation of past results. In Experiment 1, subjects named high- and low-frequency regular words in the context of either low-frequency exception words (e.g., pint) or nonwords (e.g., flirp). Frequency effects (faster pronunciation latencies for high-frequency words) were attenuated in the nonword context, consistent with the notion that nonwords emphasize the characteristics of the frequency-insensitive nonlexical pathway. Importantly, we also assessed memory for targets, and a similar attenuation of the frequency effect in recognition memory was observed in the nonword condition. Converging evidence was obtained in a second experiment in which a variable that was more sensitive to the nonlexical pathway (orthographic neighborhood size) was manipulated. The results indicated that both speeded pronunciation performance and memory performance were relatively attenuated in the low-frequency exception word context in comparision with the nonword context. The opposing influences of list context type for word frequency and orthographic neighborhood size effects in speeded pronunciation and memory performance provide strong support for the pathway control model, as opposed to the time criterion model.     

Lexical competition is enhanced in the left hemisphere: evidence from different types of orthographic neighbors

Two divided visual field lexical decision experiments were conducted to examine the role of the cerebral hemispheres in orthographic neighborhood effects. In Experiment 1, we employed two types of words: words with many substitution neighbors (high-N) and words with few substitution neighbors (low-N). Results showed a facilitative effect of N in the left visual field (i.e., right hemisphere) and an inhibitory effect of N in the right visual field (left hemisphere). In Experiment 2, we examined whether the inhibitory effect of the higher frequency neighbors increases in the left hemisphere as compared to the right hemisphere. To go beyond the usual N-metrics, we selected words with (or without) higher frequency neighbors (addition, deletion, or transposition neighbors). Results showed that the inhibitory effect of neighborhood frequency is enhanced in the right visual field. We examine the implications of these findings for the orthographic coding schemes employed by the models of visual word recognition.     

Neighborhood frequency effects and letter visibility in visual word recognition.

Two experiments are described that measured lexical decision latencies and errors to five-letter French words with a single higher frequency orthographic neighbor and control words with no higher frequency neighbors. The higher frequency neighbor differed from the stimulus word by either the second letter (e.g., ASTRE-AUTRE) or the fourth letter (CHOPE-CHOSE). Neighborhood frequency effects were found to interact with this factor, and significant interference was observed only to CHOPE-type words. The effects of neighborhood frequency were also found to interact with the position of initial fixation in the stimulus word (either the second letter or the fourth letter). Interference was greatly reduced when the initial fixation was on the critical disambiguating letter (i.e., the letter P in CHOPE). Moreover, word recognition was improved when subjects initially fixated the second letter relative to when they initially fixated the fourth letter of a five-letter word, but this second-letter advantage practically disappeared when the stimulus differed from a more frequent word by its fourth letter. The results are interpreted in terms of the interaction between visual and lexical factors in visual work recognition.     

Children like dense neighborhoods: Orthographic neighborhood density effects in novel readers

Previous evidence with English beginning readers suggests that some orthographic effects, such as the orthographic neighborhood density effects, could be stronger for children than for adults. Particularly, children respond more accurately to words with many orthographic neighbors than to words with few neighbors. The magnitude of the effects for children is much higher than for adults, and some researchers have proposed that these effects could be progressively modulated according to reading expertise. The present paper explores in depth how children from 1st to 6th grade perform a lexical decision with words that are from dense or sparse orthographic neighborhoods, attending not only to accuracy measures, but also to response latencies, through a computer-controlled task. Our results reveal that children (like adults) show clear neighborhood density effects, and that these effects do not seem to depend on reading expertise. Contrarily to previous claims, the present work shows that orthographic neighborhood effects are not progressively modulated by reading skill. Further, these data strongly support the idea of a general language-independent preference for using the lexical route instead of grapheme-to-phoneme conversions, even in beginning readers. The implications of these results for developmental models in reading and for models in visual word recognition and orthographic encoding are discussed.     

A compilation of 800 word neighborhoods by frequency

A number of inconsistencies are evident in the literature examining word-neighborhood size and frequency effects. One reason for the inconsistency may be that there are no standardized materials and criteria used in the different studies. Each experimenter has devised his or her word neighborhoods using different criteria for neighborhood size and frequency. The purpose of the present study was to develop a standardized set of word neighborhoods. Eight hundred orthographic neighborhoods were constructed with 4- and 5-letter words. The word lists were devised relative to the key elements that have been identified in the literature: (1) target-word frequency, (2) number of words in the neighborhood, (3) number of words higher in frequency than the target word, (4) number of letter positions contributing to the neighborhood, and (5) summation of the frequency of all neighbors (providing a standard metric for high- vs. low-frequency neighborhoods).     

Automatic vigilance for negative words in lexical decision and naming: comment on Larsen, Mercer, and Balota (2006)

An automatic vigilance hypothesis states that humans preferentially attend to negative stimuli, and this attention to negative valence disrupts the processing of other stimulus properties. Thus, negative words typically elicit slower color naming, word naming, and lexical decisions than neutral or positive words. Larsen, Mercer, and Balota analyzed the stimuli from 32 published studies, and they found that word valence was confounded with several lexical factors known to affect word recognition. Indeed, with these lexical factors covaried out, Larsen et al. found no evidence of automatic vigilance. The authors report a more sensitive analysis of 1011 words. Results revealed a small but reliable valence effect, such that negative words (e.g., "shark") elicit slower lexical decisions and naming than positive words (e.g., "beach"). Moreover, the relation between valence and recognition was categorical rather than linear; the extremity of a word's valence did not affect its recognition. This valence effect was not attributable to word length, frequency, orthographic neighborhood size, contextual diversity, first phoneme, or arousal. Thus, the present analysis provides the most powerful demonstration of automatic vigilance to date.     

Do transposed-letter effects occur across lexeme boundaries?

A masked priming lexical decision experiment was conducted to examine whether or not assignment of letter position in a word can be influenced by lexeme boundaries. The experiment was run in Basque, which is a strongly agglutinating language with a high proportion of inflected and compound words. Nonword primes were created by transposing two nonadjacent letters that crossed or did not cross morphological boundaries. Specifically, we compared morphologically complex prime-target pairs (e.g.,arbigide-ARGIBIDE) with orthographic controls (e.g.,arkipide-ARGIBIDE; note that ARGIBIDE is a compound of ARGI + BIDE) and noncompound pairs (e.g.,ortakila-ORKATILA) with orthographic controls (e.g.,orbahila-ORKATILA). Results showed that transposed-letter effects were virtually the same for compound and noncompound words, both when the orthographic control condition was used as a baseline and when the identity condition was used as a baseline. Thus, transposed-letter similarity effects seem to be orthographic in nature. We examine the implications of these results for the models of visual word recognition.     

Similarity relations among spoken words: The special status of rimes in English

This paper presents an analysis of the distribution of phonological similarity relations among monosyllabic spoken words in English. It differs from classical analyses of phonological neighborhood density (e.g., Luce &; Pisoni, 1998) by assuming that not all phonological neighbors are equal. Rather, it is assumed that the phonological lexicon has psycholinguistic structure. Accordingly, in addition to considering thenumber of phonological neighbors for any given word, it becomes important to consider thenature of these neighbors. If one type of neighbor is more dominant, neighborhood density effects may reflect levels of segmental representation other than the phoneme, particularly prior to literacy. Statistical analyses of the nature of phonological neighborhoods in terms ofrime neighbors (e.g.,hat/cat),consonant neighbors (e.g.,hat/hit), andlead neighbors (e.g.,hat/ham) were thus performed for all monosyllabic words in the Celex corpus (4,086 words). Our results show that most phonological neighbors are rime neighbors (e.g.,hat/cat) in English. Similar patterns were found when a corpus of words for which age-of-acquisition ratings were available was analyzed. The resultant database can be used as a tool for controlling and selecting stimuli when the role of lexical neighborhoods in phonological development and speech processing is examined.