Effect Of Phonological Neighborhood Density Research Articles

Investigating the effects of phonological neighborhood density, word frequency, and phoneme confusability on the English word recognition by native speakers of Japanese

This study aims to bridge the gap between previous research on the impact of phonological neighborhood density on word identification, which did not consider phoneme confusability, and studies on phoneme identification and discrimination, which did not account for the effects of phonological neighborhood density. Native Japanese listeners participated in this study, where they were tasked with identifying monosyllabic and disyllabic English words. The words varied in both phonological neighborhood density and word frequency and were produced by native speakers of American English and Japanese. Participants responded by typing the words they heard. The findings of this study indicated that there were no significant effects of phonological neighborhood density on word identification. However, frequent words were identified with greater accuracy compared to infrequent words. Moreover, words produced by native speakers of American English were more accurately identified than those produced by Japanese speakers. Japanese listeners' inaccurate perception of phonemes has resulted in word identification errors in both dense and sparse phonological neighborhoods. For example, they often mistakenly identify /l/ as /r/ and vice versa. Low and central vowels /æ, ɑ, ʌ/ are frequently misidentified as one another. These confusions are commonly observed among Japanese learners of English.

Discourse fluency modulates spoken word recognition in monolingual and L2 speakers

AbstractWe investigated whether fluent language production is associated with greater skill in resolving lexical competition during spoken word recognition and ignoring irrelevant information in non-linguistic tasks. Native English monolinguals and native English L2 learners, who varied on measures of discourse/verbal fluency and cognitive control, identified spoken English words from dense (e.g., BAG) and sparse (e.g., BALL) phonological neighborhoods in moderate noise. Participants were slower in recognizing spoken words from denser neighborhoods. The inhibitory effect of phonological neighborhood density was smaller for English monolinguals and L2 learners with higher speech production fluency, but was unrelated to cognitive control as indexed by performance on the Simon task. Converging evidence from within-language effects in monolinguals and cross-language effects in L2 learners suggests that fluent language production involves a competitive selection process that may not engage all domain-general control mechanisms. Results suggest that language experience may capture individual variation in lexical competition resolution.

The signed mental lexicon: Effects of phonological neighborhood density, iconicity, and childhood language experience

Most of what is known about the mental lexicon comes from studies of spoken language and their written forms. Signs differ from spoken/written words in two important ways that may affect lexical recognition: their phonological composition is unique (e.g., more simultaneous than serial structure; few minimal pairs) and many signs are iconic. Using an unprimed lexical decision task in American Sign Language (ASL) and the first available estimates of phonological neighborhood density for any sign language, we found that phonological neighborhood density had an inhibitory effect on latency among low frequency signs. This is the first clear evidence that phonological neighbors spontaneously compete during sign recognition. Iconicity negatively affected accuracy but not reaction times, suggesting that iconicity plays a role in task-related decision processes but not lexical retrieval. Many deaf signers have delayed first language acquisition, and we found that language deprivation had lasting, negative effects on phonological processing and sign recognition speed and accuracy. This work indicates that the lexicons of both spoken and signed languages are organized by form, that lexical recognition occurs through form-based competition (most evident for low frequency items), and that form-meaning mappings do not drive lexical access even when iconicity is pervasive in the lexicon.

Successful Implicit Vocabulary Intervention for Three Cantonese-Speaking Toddlers: A Replicated Single-Case Design.

Purpose We report on a replicated single-case design study that measured the feasibility of an expressive vocabulary intervention for three Cantonese-speaking toddlers with small expressive lexicons relative to their age. The aim was to assess the cross-cultural and cross-linguistic feasibility of an intervention method developed for English-speaking children. Method A nonconcurrent multiple-baseline design was used with four baseline data points and 16 intervention sessions per participant. The intervention design incorporated implicit learning principles, high treatment dosage, and control of the phonological neighborhood density of the stimuli. The children (24-39 months) attended 7-9 weeks of twice weekly input-based treatment in which no explicit verbal production was required from the child. Each target word was provided as input a minimum of 64 times in at least two intervention sessions. Treatment feasibility was measured by comparison of how many of the target and control words the child produced across the intervention period, and parent-reported expressive vocabulary checklists were completed for comparison of pre- and postintervention child spoken vocabulary size. An omnibus effect size for the treatment effect of the number of target and control words produced across time was calculated using Kendall's Tau. Results There was a significant treatment effect for target words learned in intervention relative to baselines, and all children produced significantly more target than control words across the intervention period. The effect of phonological neighborhood density on expressive word production could not be evaluated because two of the three children learned all target words. Conclusion The results provide cross-cultural evidence of the feasibility of a model of intervention that incorporated a high-dosage, cross-situational statistical learning paradigm to teach spoken word production to children with small expressive lexicons.

Measuring the influence of phonological neighborhood on visual word recognition with the N400: Evidence for semantic scaffolding

Research in visual word recognition has shown that phonological neighborhood density facilitates visual word recognition. The current research was designed to determine the electrophysiological effect of phonological neighborhood density (PND). In two experiments, participants made lexical decisions to words varying on phonological neighborhood while Event-related Potentials (ERPs) were recorded. Behaviorally, the results replicate previous research by showing that words with many phonological neighbors were responded to more rapidly than were words with few phonological neighbors. However, the main contribution of the current research is that it shows an effect of PND on the N400 and Late Positive Component Event-Related Potentials. In contrast to previous reports in the literature, the nature of the effect was such that the N400 was larger to words with few phonological neighbors than to words with many. Experiment 2 replicated these findings and provided estimates of the independent components’ time course and source localization. The increased N400 for small neighborhood words is thought to reflect additional semantic processing required for these words due their weaker phonological representations.

The effects of phonological neighborhood density in childhood word production and recognition in Russian are opposite to English

This study investigates how phonological neighborhood density (PND) affects word production and recognition in 4-to-6-year-old Russian children in comparison to adults. Previous experiments with English-speaking adults showed that a dense neighborhood facilitated word production but inhibited recognition whereas a sparse neighborhood inhibited production but facilitated recognition. Importantly, these effects are not universal because a reverse PND pattern was found in Spanish-speaking adults. Probably, PND effects depend on the morphological properties of language.This study focuses on PND effects in word production and recognition in terms of facilitation and inhibition in Russian. Our results are consistent with those in Spanish: Russian-speaking adults produced words with dense neighborhoods more slowly and recognized them faster than words with sparse neighborhoods. Russian children showed the same PND effect in recognition and no effect was found in production. The findings support the hypothesis that PND effects in word production and recognition are influenced by the morphological system of language.

Impaired lexical selection and fluency in post-stroke aphasia

ABSTRACTBackground: Deficits in fluent language production are a hallmark of aphasia and may arise from impairments at different levels in the language system. It has been proposed that difficulty resolving lexical competition contributes to fluency deficits.Aims: The present study tested this hypothesis in a novel way: by examining whether narrative speech production fluency is associated with difficulty resolving lexical competition in spoken word recognition as measured by sensitivity to phonological neighborhood density.Methods & Procedures: Nineteen participants with aphasia and 15 neurologically intact older adults identified spoken words that varied in phonological neighborhood density and were presented in moderate noise.Outcomes & Results: Neurologically intact participants exhibited the standard inhibitory effect of phonological neighborhood density on response times: slower recognition of spoken words from denser neighborhoods. Among participants with aphasia, the inhibitory effect of phonological neighborhood density (less accurate recognition of spoken words from denser neighborhoods) was smaller for participants with greater fluency. The neighborhood effect was larger for participants with greater receptive vocabulary knowledge, indicating that the fluency effect was not a result of general lexical deficits.Conclusions: These results are consistent with the hypothesis that impaired lexical selection is a contributing factor in fluency deficits in poststroke aphasia.

Interactions in the neighborhood: Effects of orthographic and phonological neighbors on N400 amplitude.

The present study investigated effects of phonological and orthographic neighborhood density on event-related potentials, with an aim to better specify the factors that determine N400 amplitude in single word reading paradigms. We orthogonally manipulated the number of orthographic and phonological neighbors of words using the Levenshtein Distance metric (OLD20 and PLD20, respectively). The results showed opposite effects of phonological neighborhood density (PND) as a function of orthographic neighborhood density (OND). Larger N400 amplitudes were elicited by words with high PND compared with low PND when OND was high, and smaller N400 amplitudes were observed with high PND compared with low PND words when OND was low. We interpret these findings using the notion of cross-code consistency, according to which the compatibility of orthographic and phonological representations activated by a given word influences the process of recognizing that word. Words with similar numbers of orthographic and phonological neighbors have more consistent spellings and pronunciations across the neighborhood, and generate larger N400 amplitudes.

Many neighborhoods: Phonological and perceptual neighborhood density in lexical production and perception

Abstract We examine the relationship of lexical representations, pronunciation variation, and word recognition, by investigating effects of two lexical variables: Phonological Neighborhood Density (the number of words that can be formed by a single phoneme substitution, addition, or deletion from the target word), as well as a measure of the perceptual similarity of a target word to other words in the lexicon. We show that perceptual similarity to other words affects recognition, but not production. Phonological Neighborhood Density, on the other hand, affects both word durations and recognition accuracy (words with many neighbors shorten and are difficult recognition targets). We interpret our results as indicating that effects of Phonological Neighborhood Density on pronunciation are not generally due to perceptual similarity of the target to other words. Our results are consistent with a more general line of research demonstrating effects of ‘central’ processes on ‘peripheral’ processes such as articulation, as well as effects of modality-specific properties, such as auditory similarity and motor movements, on measures thought to tap central processes.

Visibility of speech articulation enhances auditory phonetic convergence.

Talkers automatically imitate aspects of perceived speech, a phenomenon known as phonetic convergence. Talkers have previously been found to converge to auditory and visual speech information. Furthermore, talkers converge more to the speech of a conversational partner who is seen and heard, relative to one who is just heard (Dias & Rosenblum Perception, 40, 1457-1466, 2011). A question raised by this finding is what visual information facilitates the enhancement effect. In the following experiments, we investigated the possible contributions of visible speech articulation to visual enhancement of phonetic convergence within the noninteractive context of a shadowing task. In Experiment 1, we examined the influence of the visibility of a talker on phonetic convergence when shadowing auditory speech either in the clear or in low-level auditory noise. The results suggest that visual speech can compensate for convergence that is reduced by auditory noise masking. Experiment 2 further established the visibility of articulatory mouth movements as being important to the visual enhancement of phonetic convergence. Furthermore, the word frequency and phonological neighborhood density characteristics of the words shadowed were found to significantly predict phonetic convergence in both experiments. Consistent with previous findings (e.g., Goldinger Psychological Review, 105, 251-279, 1998), phonetic convergence was greater when shadowing low-frequency words. Convergence was also found to be greater for low-density words, contrasting with previous predictions of the effect of phonological neighborhood density on auditory phonetic convergence (e.g., Pardo, Jordan, Mallari, Scanlon, & Lewandowski Journal of Memory and Language, 69, 183-195, 2013). Implications of the results for a gestural account of phonetic convergence are discussed.

Effects of Phonological Neighborhood Density on Accuracy of Picture Naming in Aphasia

Effects of Phonological Neighborhood Density on Accuracy of Picture Naming in Aphasia

Neighborhood-conditioned patterns in phonetic detail: Relating coarticulation and hyperarticulation

The experiments presented here provide a careful phonetic description of the effects of phonological neighborhood density (operationalized as relative neighborhood frequency) on speech production: not only on hyperarticulation (which has been described elsewhere as well (e.g., Wright, 2004a, 2004b), but also on two types of coarticulation. Acoustic analysis of elicited American English data with varying neighborhood properties reveals an increased degree of coarticulation in words with a high neighborhood frequency (i.e., many neighbors with high summed frequencies), as well as increased hyperarticulation. Both nasal coarticulation (measured as degree of vowel nasality) and vowel-to-vowel coarticulation (measured as F1/F2 deviation from canonical vowel quality) display this pattern in both coarticulatory directions (anticipatory and carryover). These findings extend the current descriptions of lexically-conditioned phonetic effects to new phonetic features and new lexical structures, as well as speak to the relationship between hyperarticulation and coarticulation. The pattern of co-occurrence of hyperarticulation and coarticulation demonstrates that these two phonetic phenomena are confluent (rather than inversely occurrent) but independent, facts which inform both articulatory and functional models of coarticulation. Finally, various accounts of these neighborhood-conditioned effects on production, both those relating the effects to neighborhood influences in lexical perception and those that do not, are discussed.

Distributional analyses in auditory lexical decision: Neighborhood density and word-frequency effects

In the present article, the effects of phonological neighborhood density and word frequency in spoken word recognition were examined using distributional analyses of response latencies in auditory lexical decision. A density x frequency interaction was observed in mean latencies; frequency effects were larger for low-density words than for high-density words. Distributional analyses further revealed that for low-density words, frequency effects were reflected in both distributional shifting and skewing, whereas for high-density words, frequency effects were purely mediated by distributional skewing. The results suggest that word frequency plays a role in early auditory word recognition only when there is relatively little competition between similar-sounding words, and that frequency effects in high-density words reflect postlexical checking.

Effect of phonological neighborhood density on word duration in spontaneous speech.

It has been widely shown that words with many phonological neighbors are harder to recognize than words with few neighbors (L. & Pisoni 1998, among others). However, the effect of phonological neighborhood density on word production is less clear. On one hand, high‐density words are easier to produce (Vitevitch 1997, 2002), which suggests that they should be reduced in speech. Meanwhile, these words are often hyperarticulated, probably to make it easier for the listener (Wright 1997, Munson & Solomon 2004, Scarborough 2002). The present work aims to distinguish the two accounts by examining the effect of neighborhood density on word duration. We use data from the Buckeye corpus, which has 40 American English speakers, each recorded for about an hour. A mixed‐effect model is built to predict the durations of all CVC monomorphemic content words in the corpus, with speaker and word as random effects. The results show that, after controlling for other factors, neighborhood density has a small but robust negative effect on word duration, i.e., the more neighbors a word has, the shorter it becomes. The effect of average neighbor frequency is in the same direction. Present results provide unambiguous evidence for the talker‐oriented account concerning word duration.

Phonological neighbors influence word naming through the least supported phoneme.

Recent research has shown that phonological neighborhood density facilitates naming latencies. In an attempt to extend this work, the authors evaluated the effect of phonological neighborhood distribution by comparing responding to words that consisted of 3 phonemes but differed in the number of phoneme positions that could be changed to form a neighbor (i.e., 2 vs. 3 positions). The results revealed that words in which all 3 positions could be changed to form a neighbor were named more rapidly than were words in which only 2 positions could be changed. The results show that this effect occurs due to a difference between the 2 groups of words in terms of their least supported phoneme (i.e., the phoneme position within a word with which the fewest neighbors overlap). The authors show that differences in terms of the number of neighbors for the least supported phoneme can also explain past research that indicates an effect of phonological neighborhood density on naming. The authors explain the results of this research using the dual-route cascaded model of reading aloud.

The effect of phonological neighborhood density on eye movements during reading

Recent research has indicated that phonological neighbors speed processing in a variety of isolated word recognition tasks. Nevertheless, as these tasks do not represent how we normally read, it is not clear if phonological neighborhood has an effect on the reading of sentences for meaning. In the research reported here, we evaluated whether phonological neighborhood density influences reading of target words embedded in sentences. The eye movement data clearly revealed that phonological neighborhood facilitated reading. This was evidenced by shorter fixations for words with large neighborhoods relative to words with small neighborhoods. These results are important in indicating that phonology is a crucial component of reading and that it affects early lexical processing.

The effect of phonological neighborhood density and word frequency on vowel production and perception in clear speech

Previous research showed that phonological neighborhood density and word frequency influence word recognition (Luce and Pisoni, 1998) and vowel production (Wright, 2002; Munson and Solomon, 2004; Munson, to appear), suggesting an interaction of lexical and phonetic factors in speech production and perception Here, we explore whether hyperarticulated, intelligibility-enhancing clear speech shows similar sensitivity to lexical-level structure. Nine American English talkers (five females, four males) produced 40 monosyllabic easy (frequent words with few lexical neighbors) and hard (infrequent words with many lexical neighbors) words in conversational and clear speech. Twenty-four subjects participated in a word-in-noise listening test. Results revealed a large effect of style on intelligibility and vowel production: words were more intelligible and vowels were longer and more dispersed in clear compared to conversational speech. Moreover, the female talkers produced larger vowel spaces than male talkers in both speaking styles. Vowels in hard words were marginally more dispersed than vowels in easy words in both speaking styles. However, within both speaking styles, easy and hard words were equally intelligible and of approximately equal duration. These results showed that phonetic properties of vowels were enhanced equally in clear speech regardless of their lexical properties.

Phonological neighborhood density in the picture naming of young children who stutter: Preliminary study

The purpose of this study was to assess the effect of phonological neighborhood density on the speech reaction time (SRT) and errors of children who do and do not stutter during a picture-naming task. Participants were nine 3–5-year-old children who stutter (CWS) matched in age and gender to nine children who do not stutter (CWNS). Initial analyses indicated that both CWNS and CWS were significantly faster (i.e., exhibited shorter SRTs) and more accurate on phonologically sparse than phonologically dense words, findings consistent with those found with older children ( Newman & German, 2002). Further analyses indicated that talker group differences in receptive language scores weakened these findings. These preliminary findings were taken to suggest that phonological neighborhood density appears to influence the picture-naming speed and accuracy of preschool-aged children. Educational objectives: The reader will learn about and be able to: (1) recognize the relevance of examining phonological variables in relation to childhood stuttering; and (2) describe the method of measuring speech reaction times and errors during a picture-naming task as a means of assessing linguistic skills.

The Effect of Phonological Neighborhood Density on Vowel Articulation

Recent literature suggests that phonological neighborhood density and word frequency can affect speech production, in addition to the well-documented effects that they have on speech perception. This article describes 2 experiments that examined how phonological neighborhood density influences the durations and formant frequencies of adults' productions of vowels in real words. In Experiment 1, 10 normal speakers produced words that covaried in phonological neighborhood density and word frequency. Infrequent words with many phonological neighbors were produced with shorter durations and more expanded vowel spaces than frequent words with few phonological neighbors. Results of this experiment confirmed that this effect was not related to the duration of the vowels constituting the high- and low-density words. In Experiment 2, 15 adults produced words that varied in both word frequency and neighborhood density. Neighborhood density affected vowel articulation in both high- and low-frequency words. Moreover, frequent words were produced with more contracted vowel spaces than infrequent words. There was no interaction between these factors, and the vowel duration did not vary as a function of neighborhood density. Taken together, the results suggest that neighborhood density affects vowel production independent of word frequency and vowel duration.