Phonological Word Forms Research Articles

Keywords in the mental lexicon.

Network science draws from a number of fields to examine complex systems using nodes to represent individuals and connections to represent relationships between individuals to form a network. This approach has been used in several areas of Psychology to illustrate the influence that the structure of a network has on processing in that system. In the present study the concept of keyplayers in a network (Borgatti, 2006) was examined in the domain of Psycholinguistics. Keyplayers are nodes in a network that, when removed, result in the network fracturing into several smaller components. A set of such nodes was found in a network of phonological word-forms as was another set of foil words, comparable to the "keywords" on a number of lexical and network characteristics. In three conventional psycholinguistic tasks keywords were responded to more quickly and accurately than the foils. A similar trend was observed in an analysis of the keywords and foils (and another set of foils) in the English Lexicon Project. These results open avenues for further exploration of keywords in various areas of language processing, and demonstrate the utility of the network science approach to psycholinguistics and psychology more generally.

Phonological recovery in Spanish developmental dyslexics through the tip-of-the-tongue paradigm.

Developmental dyslexics have difficulties accessing and retrieving the phonological form of words, in the absence of a deficit at the semantic level. The aim of this work was to study, through the Tip-of-the-tongue (TOT) paradigm, the problems of lexical access in Spanish-speaking developmental dyslexics and the relationship with their phonological awareness. A group of developmental dyslexics (14) and other children without reading difficulties (14), aged 7 to 12, performed a picture naming task of medium and low frequency and a task of phonological awareness. The results indicated that dyslexic children generally show a greater number of TOT phenomena than the control group. Despite being able to provide semantic information of the drawing, they had difficulties retrieving partial phonological information. These results indicate that developmental dyslexic children have particular difficulty in accessing the phonological form of words, which may be interesting for the development of intervention programs for these children.

Tip-of-the-tongue (TOT) states and cross-linguistic transfer

This study examined cross-linguistic transfer in oral language skills in a sample of 50 native Hebrew speakers who learned English as a second language. The ability to retrieve phonological forms of words in naming, as manifested by the tendency to experience tip-of-the-tongue states, was correlated across languages. We also found within and across language correlations between this ability and grammatical accuracy, lexical diversity, and syntactic complexity in second language narratives. These findings are consistent with the transfer across languages in oral language skills and provide insights into the processes linking phonological and higher level encoding in production of connected speech.

Phonological facilitation of object naming in agrammatic and logopenic primary progressive aphasia (PPA)

Phonological processing deficits are characteristic of both the agrammatic and logopenic subtypes of primary progressive aphasia (PPA-G and PPA-L). However, it is an open question which substages of phonological processing (i.e., phonological word form retrieval, phonological encoding) are impaired in these subtypes of PPA, as well as how phonological processing deficits contribute to anomia. In the present study, participants with PPA-G (n = 7), participants with PPA-L (n = 7), and unimpaired controls (n = 17) named objects as interfering written words (phonologically related/unrelated) were presented at different stimulus onset asynchronies (SOAs) of 0, +100, +300, and +500 ms. Phonological facilitation (PF) effects (faster naming times with phonologically related interfering words) were found for the controls and PPA-L group only at SOA = 0 and +100 ms. However, the PPA-G group exhibited protracted PF effects (PF at SOA = 0, +100, and +300 ms). These results may reflect deficits in phonological encoding in PPA-G, but not in PPA-L, supporting the neuropsychological reality of this substage of phonological processing and the distinction between these two PPA subtypes.

Discovering words in fluent speech: the contribution of two kinds of statistical information.

To efficiently segment fluent speech, infants must discover the predominant phonological form of words in the native language. In English, for example, content words typically begin with a stressed syllable. To discover this regularity, infants need to identify a set of words. We propose that statistical learning plays two roles in this process. First, it provides a cue that allows infants to segment words from fluent speech, even without language-specific phonological knowledge. Second, once infants have identified a set of lexical forms, they can learn from the distribution of acoustic features across those word forms. The current experiments demonstrate both processes are available to 5-month-old infants. This demonstration of sensitivity to statistical structure in speech, weighted more heavily than phonological cues to segmentation at an early age, is consistent with theoretical accounts that claim statistical learning plays a role in helping infants to adapt to the structure of their native language from very early in life.

The benefit of orthographic support for oral vocabulary learning in children with Down syndrome

Children with Down syndrome typically have weaknesses in oral language, but it has been suggested that this domain may benefit from learning to read. Amongst oral language skills, vocabulary is a relative strength, although there is some evidence of difficulties in learning the phonological form of spoken words. This study investigated the effect of orthographic support on spoken word learning with seventeen children with Down syndrome aged seven to sixteen years and twenty-seven typically developing children aged five to seven years matched for reading ability. Ten spoken nonwords were paired with novel pictures; for half the nonwords the written form was also present. The spoken word learning of both groups did not differ and benefited to the same extent from the presence of the written word. This suggests that compared to reading-matched typically developing children, children with Down syndrome are not specifically impaired in phonological learning and benefit equally from orthographic support.

Naming Abilities in Low-Proficiency Second Language Learners

Difficulties in second language (L2) learning are often associated with recognizable learning difficulties in native language (L1), such as in dyslexia. However, some individuals have low L2 proficiency but intact L1 reading skills. These L2 learners experience frequent tip-of-the-tongue states while naming in L1, which indicates that they have a weakness in retrieval of phonological codes of words. The authors hypothesized that if naming ability is shared across languages, this difficulty would reemerge in L2 naming, which was tested using the tip-of-the-tongue experimental paradigm. Consistent with this hypothesis, low-proficiency L2 learners (n = 15) reported more tip-of-the-tongue states, more frequently mispronounced correctly retrieved words, and benefited less from phonological cuing compared to high-proficiency L2 learners (n = 23). It is notable that low-proficiency L2 learners performed worse than individuals with dyslexia (n = 16) on some of these measures, despite the same level of L2 proficiency. These results indicate that L2 naming difficulties of low-proficiency L2 learners are a manifestation not merely of their low L2 proficiency but rather of a general weakness in phonological word form retrieval, which is shared across languages. More broadly, the study provides further evidence for the existence of a distinct profile of cognitive weaknesses characteristic of the behavioral phenotype of low-proficiency L2 learners.

Neural mechanisms underlying the facilitation of naming in aphasia using a semantic task: an fMRI study

BackgroundPrevious attempts to investigate the effects of semantic tasks on picture naming in both healthy controls and people with aphasia have typically been confounded by inclusion of the phonological word form of the target item. As a result, it is difficult to isolate any facilitatory effects of a semantically-focused task to either lexical-semantic or phonological processing. This functional magnetic resonance imaging (fMRI) study examined the neurological mechanisms underlying short-term (within minutes) and long-term (within days) facilitation of naming from a semantic task that did not include the phonological word form, in both participants with aphasia and age-matched controls.ResultsBehavioral results showed that a semantic task that did not include the phonological word form can successfully facilitate subsequent picture naming in both healthy controls and individuals with aphasia. The whole brain neuroimaging results for control participants identified a repetition enhancement effect in the short-term, with modulation of activity found in regions that have not traditionally been associated with semantic processing, such as the right lingual gyrus (extending to the precuneus) and the left inferior occipital gyrus (extending to the fusiform gyrus). In contrast, the participants with aphasia showed significant differences in activation over both the short- and the long-term for facilitated items, predominantly within either left hemisphere regions linked to semantic processing or their right hemisphere homologues.ConclusionsFor control participants in this study, the short-lived facilitation effects of a prior semantic task that did not include the phonological word form were primarily driven by object priming and episodic memory mechanisms. However, facilitation effects appeared to engage a predominantly semantic network in participants with aphasia over both the short- and the long-term. The findings of the present study also suggest that right hemisphere involvement may be supportive rather than maladaptive, and that a large distributed perisylvian network in both cerebral hemispheres supports the facilitation of naming in individuals with aphasia.

Complex network structure influences processing in long-term and short-term memory

Complex networks describe how entities in systems interact; the structure of such networks is argued to influence processing. One measure of network structure, clustering coefficient, C, measures the extent to which neighbors of a node are also neighbors of each other. Previous psycholinguistic experiments found that the C of phonological word-forms influenced retrieval from the mental lexicon (that portion of long-term memory dedicated to language) during the on-line recognition and production of spoken words. In the present study we examined how network structure influences other retrieval processes in long- and short-term memory. In a false-memory task—examining long-term memory—participants falsely recognized more words with low- than high-C. In a recognition memory task—examining veridical memories in long-term memory—participants correctly recognized more words with low- than high-C. However, participants in a serial recall task—examining redintegration in short-term memory—recalled lists comprised of high-C words more accurately than lists comprised of low-C words. These results demonstrate that network structure influences cognitive processes associated with several forms of memory including lexical, long-term, and short-term.

Independent Distractor Frequency and Age-of-Acquisition Effects in Picture–Word Interference: fMRI Evidence for Post-lexical and Lexical Accounts according to Distractor Type

In two fMRI experiments, participants named pictures with superimposed distractors that were high or low in frequency or varied in terms of age of acquisition. Pictures superimposed with low-frequency words were named more slowly than those superimposed with high-frequency words, and late-acquired words interfered with picture naming to a greater extent than early-acquired words. The distractor frequency effect (Experiment 1) was associated with increased activity in left premotor and posterior superior temporal cortices, consistent with the operation of an articulatory response buffer and verbal self-monitoring system. Conversely, the distractor age-of-acquisition effect (Experiment 2) was associated with increased activity in the left middle and posterior middle temporal cortex, consistent with the operation of lexical level processes such as lemma and phonological word form retrieval. The spatially dissociated patterns of activity across the two experiments indicate that distractor effects in picture-word interference may occur at lexical or postlexical levels of processing in speech production.

Dynamic-intentional thalamic aphasia: a failure of lexical-semantic self-activation

Background: Previous research has described patients with aphasia from thalamic lesions, some of whom were non-fluent with intact comprehension, others who were fluent with impaired comprehension, and some of whom are non-fluent with impaired comprehension. Whereas these three subtypes usually have normal repetition, they had impaired naming, suggesting a deficit in lexical (phonological word forms)-semantic processing. We report a patient with a left thalamic hemorrhage in which lexical-semantic representations appear to be intact but the patient demonstrates an inability to spontaneously activate his lexical-semantic system Methods: A 82-year-old, right-handed man presented with decreased verbal fluency and memory loss following a thalamic hemorrhage. Neuropsychological assessment revealed significant decrements in verbal fluency with intact naming, comprehension, repetition and vocabulary. Conclusions: To the best of our knowledge this pattern of language disturbance, which mirrors dynamic aphasia induced by frontal lesions, has not previously been described with thalamic injury. The thalamus has strong connections with the frontal lobe and rather than degradation of lexical-semantic representations, this patient's thalamic lesion probably induced frontal lobe dysfunction with a failure to spontaneously active lexical semantic representations.

What do foreign neighbors say about the mental lexicon?

A corpus analysis of phonological word-forms shows that English words have few phonological neighbors that are Spanish words. Concomitantly, Spanish words have few phonological neighbors that are English words. These observations appear to undermine certain accounts of bilingual language processing, and have significant implications for the processing and representation of word-forms in bilinguals.

Tip-of-the-tongue states reveal age differences in the syllable frequency effect.

Syllable frequency has been shown to facilitate production in some languages but has yielded inconsistent results in English and has never been examined in older adults. Tip-of-the-tongue (TOT) states represent a unique type of production failure where the phonology of a word is unable to be retrieved, suggesting that the frequency of phonological forms, like syllables, may influence the occurrence of TOT states. In the current study, we investigated the role of first-syllable frequency on TOT incidence and resolution in young (18-26 years of age), young-old (60-74 years of age), and old-old (75-89 years of age) adults. Data from 3 published studies were compiled, where TOTs were elicited by presenting definition-like questions and asking participants to respond with "Know," "Don't Know," or "TOT." Young-old and old-old adults, but not young adults, experienced more TOTs for words beginning with low-frequency first syllables relative to high-frequency first syllables. Furthermore, age differences in TOT incidence occurred only for words with low-frequency first syllables. In contrast, when a prime word with the same first syllable as the target was presented during TOT states, all age groups resolved more TOTs for words beginning with low-frequency syllables. These findings support speech production models that allow for bidirectional activation between conceptual, lexical, and phonological forms of words. Furthermore, the age-specific effects of syllable frequency provide insight into the progression of age-linked changes to phonological processes. (PsycINFO Database Record (c) 2010 APA, all rights reserved).

The arbitrariness of the sign: Learning advantages from the structure of the vocabulary.

Recent research has demonstrated that systematic mappings between phonological word forms and their meanings can facilitate language learning (e.g., in the form of sound symbolism or cues to grammatical categories). Yet, paradoxically from a learning viewpoint, most words have an arbitrary form-meaning mapping. We hypothesized that this paradox may reflect a division of labor between 2 different language learning functions: arbitrariness facilitates learning specific word meanings and systematicity facilitates learning to group words into categories. In a series of computational investigations and artificial language learning studies, we varied the extent to which the language was arbitrary or systematic. For both the simulations and the behavioral studies, we found that the optimal structure of the vocabulary for learning incorporated this division of labor. Corpus analyses of English and French indicate that these predicted patterns are also found in natural languages.

Conceptual and non-conceptual repetition priming in category exemplar generation: Evidence from bilinguals

One measure of conceptual implicit memory is repetition priming in the generation of exemplars from a semantic category, but does such priming transfer across languages? That is, do the overlapping conceptual representations for translation equivalents provide a sufficient basis for such priming? In Experiment 1 (N=96) participants carried out a deep encoding task, and priming between languages was statistically reliable, but attenuated, relative to within-language priming. Experiment 2 (N=96) replicated the findings of Experiment 1 and assessed the contributions of conceptual and non-conceptual processes using a levels-of-processing manipulation. Words that underwent shallow encoding exhibited within-language, but not between-language, priming. Priming in shallow conditions cannot therefore be explained by incidental activation of the concept. Instead, part of the within-language priming effect, even under deep-encoding conditions, is due to increased availability of language-specific lemmas or phonological word forms.

Do children with dyslexia and/or specific language impairment compensate for place assimilation? Insight into phonological grammar and representations

English speakers have to recognize, for example, that te[m] in te[m] pens is a form of ten, despite place assimilation of the nasal consonant. Children with dyslexia and specific language impairment (SLI) are commonly proposed to have a phonological deficit, and we investigate whether that deficit extends to place assimilation, as a way of probing phonological representations and phonological grammar. Children with SLI plus dyslexia, SLI only, and dyslexia only listened to sentences containing a target word in different assimilatory contexts—viable, unviable, and no change—and pressed a button to report hearing the target. The dyslexia-only group did not differ from age-matched controls, but the SLI groups showed more limited ability to accurately identify words within sentences. Once this factor was taken into account, the groups did not differ in their ability to compensate for assimilation. The results add to a growing body of evidence that phonological representations are not necessarily impaired in dyslexia. SLI children's results suggest that they too are sensitive to this aspect of phonological grammar, but are more liberal in their acceptance of alternative phonological forms of words. Furthermore, these children's ability to reject alternative phonological forms seems to be primarily limited by their vocabulary size and phonological awareness abilities.

Argument structure deficits in aphasia: New perspective on models of lexical production

Background: The study explores the ability of fluent and non-fluent aphasic patients to produce verbs using the appropriate argument structure, i.e., a feature specifying the number and type of participants in the event described by the verb. According to Chomsky's Minimalist Program (1995), the lexical entry of a verb contains information about the number of arguments and the thematic roles assigned, which is then mapped onto the sentence argument structure, while Bock and Levelt's (1994; see also Levelt, Roelofs, & Meyer, 1999) model of lexical production assumes that the information regarding verb argument structure (VAS) is part of the lemma and is accessed before the retrieval of the phonological word form, i.e., the lexeme. Aim: Participants were tested to investigate their ability to map thematic information onto the corresponding syntactic argument structure. Methods & Procedures: Seven aphasic patients (five suffering from non-fluent aphasia with agrammatism and two from fluent aphasia) and ten neurologically unimpaired individuals participated in the study. They were given a picture description task formulated in two conditions: in the first condition they were asked to provide a free description of the image, while in the second condition they had to complete the sentence structure provided by the examiner. Patients showing deficits in verb production were also tested for the use of prepositions within prepositional compounds and in a sentence context. Outcomes & Results: Four agrammatic patients and one fluent aphasic patient scored a high rate of argument structure errors in the selection of the appropriate verb, which was employed with an incorrect argument structure. Furthermore, these patients tended to substitute rather than to omit prepositions when required to fill the gap in a sentence. Conclusions: Our results indicate an impaired access to (VAS) and/or in mapping the thematic role information onto the syntactic argument structure. This deficit, which was found in both the agrammatic and the fluent aphasic patients, conflicts with an alternative interpretation of verb production errors in terms of omission of the preposition introducing the manner adjunct. Data support the hypothesis of retrieval of the verb lexeme without prior access to the corresponding lemma, where information about argument structure is stored.

A model linking immediate serial recall, the Hebb repetition effect and the learning of phonological word forms

We briefly review the considerable evidence for a common ordering mechanism underlying both immediate serial recall (ISR) tasks (e.g. digit span, non-word repetition) and the learning of phonological word forms. In addition, we discuss how recent work on the Hebb repetition effect is consistent with the idea that learning in this task is itself a laboratory analogue of the sequence-learning component of phonological word-form learning. In this light, we present a unifying modelling framework that seeks to account for ISR and Hebb repetition effects, while being extensible to word-form learning. Because word-form learning is performed in the service of later word recognition, our modelling framework also subsumes a mechanism for word recognition from continuous speech. Simulations of a computational implementation of the modelling framework are presented and are shown to be in accordance with data from the Hebb repetition paradigm.

Auditory context effects in picture naming investigated with event-related fMRI

Naming an object entails a number of processing stages, including retrieval of a target lexical concept and encoding of its phonological word form. We investigated these stages using the picture-word interference task in an fMRI experiment. Participants named target pictures in the presence of auditorily presented semantically related, phonologically related, or unrelated distractor words or in isolation. We observed BOLD signal changes in left-hemisphere regions associated with lexical-conceptual and phonological processing, including the mid-to-posterior lateral temporal cortex. However, these BOLD responses manifested as signal reductions for all distractor conditions relative to naming alone. Compared with unrelated words, phonologically related distractors showed further signal reductions, whereas only the pars orbitalis of the left inferior frontal cortex showed a selective reduction in response in the semantic condition. We interpret these findings as indicating that the word forms of lexical competitors are phonologically encoded and that competition during lexical selection is reduced by phonologically related distractors. Since the extended nature of auditory presentation requires a large portion of a word to be presented before its meaning is accessed, we attribute the BOLD signal reductions observed for semantically related and unrelated words to lateral inhibition mechanisms engaged after target name selection has occurred, as has been proposed in some production models.

Homophone density and phonological frequency in Chinese word recognition

The present research factorially examined the effects of homophone density, visual frequency, and phonological frequency (defined here as the cumulative frequency of homophone mates) in Chinese visual word recognition. Stimuli were compound characters matched in semantic and phonetic radical neighbourhood density and in average visual frequency of orthographic neighbours. In contrast to a previous study with Chinese by Ziegler, Tan, Perry, and Montant (2000), no facilitative effect of phonological frequency was observed. Unlike previous findings with English readers of inhibitory effects of homophones, a facilitative effect of homophone density – restricted to low visual frequency words – was obtained for Chinese in both lexical decision (Exp. 1) and naming (Exp. 2), similar to Ziegler et al. (2000). Our results suggest that, when there is less possibility of sublexical competition between similar spellings, homophone density effects are facilitatory. This outcome supports theoretical positions regarding the mental representation of homophones that assume a single representation for homophones at the phonological word form level.