Strategic reliance on phonological mediation in lexical access

The present study investigated strategic variation in reliance on phonological mediation in visual word recognition. In Experiment 1, semantically related or unrelated word primes preceded word, pseudohomophone (e.g.,trane), or nonpseudohomophone (e.g.,trank) targets in a lexical decision task. Semantic priming effects were found for words, and response latencies to pseudohomophones were longer in related than in unrelated prime conditions. In Experiment 2, related or unrelated word primes preceded word or pseudohomophone targets. A relatedness effect was found for words, although it was significant at a 600-msec prime-target stimulus onset asynchrony (SOA) and not at a 200-msec SOA. There was no relatedness effect for pseudohomophones. Experiment 3 was a replication of Experiment 2, except that pseudohomophones were replaced by nonpseudohomophonic orthographic controls. Facilitation effects for related target words were greater in Experiment 3 than in Experiment 2. The results reflect apparent variations in the expectation that a related prime reliably indicates that a target is a word. Although reliance on phonological mediation might be strategically contingent, there could be a brief time period in which phonologically mediated lexical access occurs automatically. Whether phonological information is maintained or suppressed subsequently depends on its overall usefulness for the task.     

Aphasia, dyslexia and the phonological coding of written words

A possible account of the reading difficulty of certain aphasic-dyslexic patients includes the notion that they are impaired in translating the written word into a phonological code via grapheme-phoneme conversion rules. This notion was tested in two experiments, both utilizing orthographically regular non-words (like dake) as stimuli. The first experiment provides an analysis of two patients' (largely successful) attempts to repeat non-words, and their (almost totally unsuccessful) attempts to read them. Second, in a lexical decision task (is this written letter-string a word or not?), the finding that normals are slowed by non-words homophonic with real words (like flore) was replicated using a modified technique. This effect, attributable to phonological coding, was not shown by the patients. At the same time, their ability to discriminate between words and non-words was essentially intact. Consideration was given to mechanisms which might underlie such patients' correct and erroneous readings of words and non-words.     

The influence of visualization of orthography on the recognition of written words]

This paper reviews the main research that has been conducted on the role of orthographic neighbourhood in visual word recognition. We focus here on the traditionally defined neighbourhood, that is corresponding to the set of words of the same length sharing all but one letter with the stimulus. Two major theoretical frameworks, namely the activation verification and the interactive activation models, assume that orthographic neighbours are activated when a written word is presented. Predictions formulated by both models for words and pseudowords on the effects of neighbourhood size (N), neighbourhood frequency (NF), and neighbourhood distribution (P), are examined in order to assess the plausibility of serial versus interactive processes. Findings from 27 empirical studies including more than 80 experiments suggest that neighbourhood effects depend on the neighbourhood indexes (N, NF, and P), on the particular tasks (lexical decision, naming, semantic categorization, perceptual identification, and reading), and on the languages (English, French, Spanish, and Dutch) that are used. The results for words can be summarized as follows: (1) In the lexical decision task, the N effect is facilitatory. The NF effect is rather inhibitory, particularly in French and Spanish experiments. The P effect is rather inhibitory in English studies, whereas the P effect for higher frequency neighbours is facilitatory in French. (2) In the perceptual identification task with a single identification response, N and NF effects are inhibitory whatever the language. (3) In the naming task, N and NF effects are facilitatory whatever the language. (4) In the semantic categorization task, an interaction effect between N and NF is found in both English and Spanish. (5) In eye movement studies, the NF effect is inhibitory in both English and French. The issue of lexical versus task-specific processes underlying neighbourhood effects in lexical identification tasks is also examined. On the whole, facilitatory N effects are usually attributed to nonlexical processes of the lexical decision task and of the naming task, whereas inhibitory neighbourhood frequency effects are usually attributed to lexical processes, at least in lexical-decision experiments and in eye-movement studies on normal reading. The distribution of higher frequency neighbours which is found to have a facilitatory effect on French words in lexical-decision experiments can be attributed to lexical processes in the interactive activation framework. The theoretical implications of the data are discussed in light of the original activation verification and interactive activation models and in recently extended versions of these models. We conclude that the lexical inhibition hypothesis which is central in the interactive activation framework is the most appropriate to account for the role of orthographic neighbourhoods in visual word recognition.     

Articulatory coding and phonological judgements on written words and pictures: The role of the phonological output buffer

Abstract

The ability of Italian subjects to make phonological judgements was investigated in three experiments. The judgements comprised initial sound similarity and stress assignment on pain of both written words and pictures. Stress assignment on both words and pictures as well as initial sound similarity on pictures required the activation of phonological lexical representations, but this was not necessarily the case for initial sound similarity judgements on word pairs. The first study assessed the effects of concurrent articulatory suppression on the judgements. Experiment 2 used a concomitant task (chewing), which shares with suppression the use of articulatory components but does not involve speech programming and production. The third experiment investigated the effects of unattended speech on the phonological judgements. The results of these three experiments showed that articulatory suppression had a significant disrupting effect on accuracy in all four conditions, while neither articulatory non-speech (chewing) or unattended auditory speech had any effect on the subjects' performance. The results suggest that these phonological judgements involve the operation of an articulatory speech output component, which is not implemented peripherally and does not require the involvement of a non-articulatory input system.     

Lexical decision in a phonologically shallow orthography

The Serbo-Croatian language is written in two alphabets, Roman and Cyrillic. Both orthographies transcribe the sounds of the language in a regular and straightforward fashion and may, therefore, be referred to as phonologically shallow in contrast to English orthography, which is phonologically deep. Most of the alphabet characters are unique to one alphabet or the other. There are, however, a number of shared characters, some of which receive the same reading and some of which receive a different reading, in the two alphabets. It is possible, therefore, to construct a variety of types of letter strings. Some of these can be read in only one way and can be either a word or nonsense. Other letter strings can be pronounced one way if read as Roman and in a distinctively different way if read as Cyrillic and can be words in both alphabets—but different words; or they can be nonsense in both alphabets or nonsense in one alphabet and a word in the other. In a lexical decision task conducted with bialphabetical readers, it was shown that words that can be read in two different ways are accepted more slowly and with greater error than words that can be read only one way. It was concluded that for the phonologically shallow writing systems of Serbo-Croatian, lexical decision proceeds with reference to the phonology.     

The role of subsyllabic structure in lexical access to printed words

Summary Three lexical-decision experiments investigated whether the subsyllabic structure of words is processed in the course of lexical access to printed words. Experiment 1 contrasted Italian words with same orthographic structure, but different subsyllabic structures. Latencies were shorter and error rates lower for words with a syllabic structure composed of fewer subsyllabic constituents. Experiment 2 ruled out the possibility that the results of Experiment 1 were due to differences in the frequency of bigrams composing the items. Bigram frequency had no effect on words of the same frequency as that of words in Experiment 1. Finally, Experiment 3 showed that it is not the number of subsyllabic constituents that affects lexical decision — rather the internal composition and frequency of the subsyllabic structure underlying a word. These results suggest that the subsyllabic structure of words is represented in abstract form in the mental lexicon and processed during lexical access. Subsyllabic structures, which are simpler and more common in the language, are more easily activated and processed, regardless of the number of subsyllabic constituents and the number of syllables composing the word.     

Semantic priming effects from single words in a lexical decision task

The present research examines the semantic priming effects of a centrally presented single prime word to which participants were instructed to either "attend and remember" or "ignore". The prime word was followed by a central probe target on which the participants made a lexical decision task. The main variables manipulated across experiments were prime duration (50 or 100 ms), the presence or absence of a mask following the prime, and the presence (or absence) and type of distractor stimulus (random set of consonants or pseudowords) on the probe display. There was a consistent interaction between the instructions and the semantic priming effects. Relative to the "attend and remember" instruction, an "ignore" instruction produced reduced positive priming from single primes presented for 100 ms, irrespective of the presence or absence of a prime mask, and regardless of whether the probe target was presented with or without distractors. Additionally, reliable negative priming was found from ignored primes presented for briefer durations (50 ms) and immediately followed by a mask. Methodological and theoretical implications of the present findings for the extant negative priming literature are discussed.     

A reason to rhyme: phonological and semantic influences on lexical access

During on-line language production, speakers rapidly select a sequence of words to express their desired meaning. The current study examines whether this lexical selection is also dependent on the existing activation of surface properties of the words. Such surface properties clearly matter in various forms of wordplay, including poetry and musical lyrics. The experiments in this article explore whether language processing more generally is sensitive to these properties. Two experiments examined the interaction between phonological and semantic features for written and verbal productions. In Experiment 1, participants were given printed sentences with a missing word, and were asked to generate reasonable completions. The completions reflected both the semantic and the surface features of the preceding context. In Experiment 2, listeners heard sentence contexts, and were asked to rapidly produce a word to complete the utterance. These spontaneous completions again incorporated surface features activated by the context. The results suggest that lexical access in naturalistic language processing is influenced by an interaction between the surface and semantic features of language.     

Time course analyses of orthographic and phonological priming effects during word recognition in a transparent orthography

In opaque orthographies, the activation of orthographic and phonological codes follows distinct time courses during visual word recognition. However, it is unclear how orthography and phonology are accessed in more transparent orthographies. Therefore, we conducted time course analyses of masked priming effects in the transparent Dutch orthography. The first study used targets with small phonological differences between phonological and orthographic primes, which are typical in transparent orthographies. Results showed consistent orthographic priming effects, yet phonological priming effects were absent. The second study explicitly manipulated the strength of the phonological difference and revealed that both orthographic and phonological priming effects became identifiable when phonological differences were strong enough. This suggests that, similar to opaque orthographies, strong phonological differences are a prerequisite to separate orthographic and phonological priming effects in transparent orthographies. Orthographic and phonological priming appeared to follow distinct time courses, with orthographic codes being quickly translated into phonological codes and phonology dominating the remainder of the lexical access phase.     

List context effects on masked phonological priming in the lexical decision task

A lexical decision experiment tested the effects of briefly presented masked primes that were homophones or pseudohomophones of target words. Different types of nonword foil (pseudohomophones, orthographically regular nonwords, orthographically irregular nonwords) were mixed with the word targets. Pseudohomophone priming effects were independent of nonword foil variations, whereas homophone priming effects varied from being facilitatory in the presence of orthographically regular nonwords, inhibitory in the presence of pseudohomophones, and null in the presence of irregular nonwords. This dissociation in the way nonword foil variations influence masked pseudohomophone and homophone priming effects in the lexical decision task is discussed within the framework of a bimodal extension of the multiple readout model of visual word recognition (Grainger & Jacobs, 1996).     

Processing lexical ambiguity and visual word recognition in a deep orthography

We investigated the effect of semantic and phonemic ambiguity on lexical decision and naming performance in the deep Hebrew orthography. Experiment 1 revealed that lexical decisions for ambiguous consonant strings are faster than those for any of the high- or low-frequency voweled alternative meanings of the same strings. These results suggested that lexical decisions for phonemically and semantically ambiguous Hebrew consonant strings are based on the ambiguous orthographic information. However, a significant frequency effect for both ambiguous and unambiguous words suggested that if vowels are present, subjects do not ignore them completely while making lexical decisions. Experiment 2 revealed that naming low-frequency voweled alternatives of ambiguous strings took significantly longer than naming the high-frequency alternatives or the unvoweled strings without a significant difference between the latter two string types. Voweled and unvoweled unambiguous strings, however, were named equally fast. We propose that semantic and phonological disambiguation of unvoweled words in Hebrew is achieved in parallel to the lexical decision, but is not required by it. Naming Hebrew words usually requires a readout of phonemic information from the lexicon.     

Further evidence for phonological constraints on visual lexical access: TOWED primes FROG

If the phonological codes of visually presented words are assembled-rapidly and automatically for use in lexical access, then words that sound alike should induce similar activity within the internal lexicon.Towed is homophonous with TOAD, which is semantically related tofrog, andbeach is homophonous withbeech, which is semantically related totree. Stimuli such as these were used in a priming-of-namingtask, in which words homophonous with associates of the target words preceded the targets at an onset asynchrony of 100 msec. Relative to spelling controls (trod, bench), the low-frequencytowed and the high-frequencybeach speeded up the naming offrog andtree, respectively, to the same degree. This result was discussed in relation to the accumulating evidence for the primacy of phonological constraints in visual lexical access. nt]mis|This research was supported in part by National Institute of Child Health and Human Development Grants HD-08945 and HD-0 1994 to the first author and Haskins Laboratories, respectively.     

Context effects in lexical access: A meta-analysis

The modularity hypothesis was evaluated in this review of 25 studies that investigated context effects in early lexical processing. Selection criteria restricted the review to priming studies and to studies that presented the target word before or at the end of the prime word. Meta-analysis was used to provide summary information about the 17 studies in the review for which effect sizes could be calculated. Overall, the analysis revealed a small effect of context on lexical access. Results provide a disconfirmation of the modularity hypothesis; although multiple interpretations of a word were sometimes accessed, the contextually appropriate interpretation was consistently more strongly activated. The lack of significant heterogeneity of variance suggests that the variability observed across studies was due to sampling error; however, task, timing of target presentation, meaning frequency, type of target, and type of context were identified as potential moderator variables.     

Naming regular and exception words: Further examination of the effect of phonological dissension among lexical neighbours

Abstract

It is generally assumed that visual word recognition is accompanied by the activation of lexical representations corresponding to words orthographically similar to the target (neighbours). With regard to the pronunciation of their constituent units, these words can either converge with or diverge from the target pronunciation. The role of the frequency of the divergent pronunciations in print-to-sound conversion was examined in a naming experiment in which subjects pronounced regular and exception words. The results showed that naming latencies for exception words were affected by the orthographic similarity of the target with frequent phonologically divergent words (enemies). In a similar vein, regular words which include the letters G or C (whose pronunciations are contextually determined) and which are orthographically similar to words favouring an incorrect pronunciation of the letter took longer to pronounce than regular controls. A delayed naming experiment indicated that these differences were not attributable to the articulatory characteristics of the items. Finally, it also appeared that enemy frequency influenced naming latencies but not regularisation rates and regularisation latencies. The results are discussed within the framework of current dual-route and parallel distributed processing models of reading.     

On the role of regular phonological variation in lexical access: evidence from voice assimilation in French

The present study investigated whether lexical access is affected by a regular phonological variation in connected speech: voice assimilation in French. Two associative priming experiments were conducted to determine whether strongly assimilated, potentially ambiguous word forms activate the conceptual representation of the underlying word. Would the ambiguous word form [sud] (either assimilated soute 'hold' or soude 'soda') facilitate "bagage" 'luggage', which is semantically related to soute but not to soude? In Experiment 1, words in either canonical or strongly assimilated form were presented as primes. Both forms primed their related target to the same extent. Potential lexical ambiguity did not modulate priming effects. In Experiment 2, the primes such as assimilated soute pronounced [sud] used in Experiment 1 were replaced with primes such as soude canonically pronounced [sud]. No semantic priming effect was obtained with these primes. Therefore, the effect observed for assimilated forms in Experiment 1 cannot be due to overall phonological proximity between canonical and assimilated forms. We propose that listeners must recover the intended words behind the assimilated forms through the exploitation of the remaining traces of the underlying form, however subtle these traces may be.     

Different methods of lexical access for words presented in the left and right visual hemifields

Right-handed adults were asked to identify by name bilaterally presented words and pronounceable nonwords. For words in the normal horizontal format, word length (number of letters) affected left visual hemifield (LVF) but not right visual hemifield (RVF) performance in Experiments 1, 2, 3, 5, and 6. This finding was made for words of high and low frequency (Experiment 6) and imageability (Experiment 5). It also held across markedly different levels of overall performance (Experiments 1 and 2), and across different relative positionings of short and long words in the LVF and RVF (Experiment 3). Experiment 4 demonstrated that the variable affecting LVF performance is the number of letters in a word, not its phonological length. For pronounceable nonwords (Experiment 7) and words in unusual formats (Experiment 8), however, length affected both LVF and RVF performance. The characteristics identified for RVF performance in these experiments also hold for the normal reading system. In this (normal) system the absence of length effects for horizontally formatted words is generally taken to reflect the processes involved in lexical access. Length effects in the normal reading system are thought to arise when lexical access for unusually formatted words and for the pronunciation of nonwords requires the short-term storage of information at a graphemic level of analysis. The characteristics of LVF performance indicate that horizontally formatted words presented to the right cerebral hemisphere can only achieve lexical access by a method that requires the short-term storage of graphemic information. This qualitative difference in methods of lexical access applies regardless of whether the right hemisphere is seen as accessing words in the left hemisphere's lexicon or words in a lexicon of its own.     

Phonotactics, neighborhood activation, and lexical access for spoken words.

Probabilistic phonotactics refers to the relative frequencies of segments and sequences of segments in spoken words. Neighborhood density refers to the number of words that are phonologically similar to a given word. Despite a positive correlation between phonotactic probability and neighborhood density, nonsense words with high probability segments and sequences are responded to more quickly than nonsense words with low probability segments and sequences, whereas real words occurring in dense similarity neighborhoods are responded to more slowly than real words occurring in sparse similarity neighborhoods. This contradiction may be resolved by hypothesizing that effects of probabilistic phonotactics have a sublexical focus and that effects of similarity neighborhood density have a lexical focus. The implications of this hypothesis for models of spoken word recognition are discussed.     

Lexical access to inflected words as measured by lateralized visual lexical decision

In two lateralized visual lexical decision experiments conducted with normal subjects, we studied hemispheric performance in the recognition of case-inflected Finnish nouns. Previous research employing mainly locative cases has indicated that such noun forms undergo morphological decomposition. The present experiments extend this finding to syntactic cases by showing that nouns with partitive or genitive endings take longer to recognize and elicit more errors than otherwise comparable monomorphemic nominative singular nouns. Morpheme-based recognition of all case-inflected forms would be a particularly appropriate solution for mental lexicon in highly inflecting languages like Finnish: it saves storage space and enables fast recognition of inflected forms not encountered before. In real words, morphological structure did not interact with visual field. However, particularly demanding, morphologically decomposable nonwords elicited more errors in the left visual field/right hemisphere than did nondecomposable nonwords. Our results suggest that at least in Finnish, both hemispheres are capable of morpheme-based access, but this mechanism is more accurate in the left than in the right hemisphere. Received: 21 May 1997 / Accepted: 19 January 1998     

Newly learned spoken words show long-term lexical competition effects

Newly learned spoken words (e.g., “cathedruke”) become fully engaged in the mental lexicon, as measured via lexical competition with their pre-existing phonological neighbours (e.g., “cathedral”), over the course of several hours or days, and this lexical restructuring is associated with sleep (Dumay & Gaskell, 2007). Here, we investigated the longer-term effects of word learning for three sets of novel words learned at different times using phoneme monitoring and repetition tasks. The effects of these exposure sessions on lexical memory were assessed in a battery of tests. Lexical decision latencies to pre-existing neighbouring words showed that lexical competition effects for the novel words remained observable 8 months after initial exposure. Furthermore, the order-of-acquisition of the novel words affected their production speed (but not recognition speed), with an advantage for earlier acquired words. The results suggest that the consolidation of novel words results in a long-term and stable change in the lexical competition process.