Competition in lexical processing of Italian noun/verb homographs

The study investigates the lexical representation of Italian noun/verb homographs, introducing a factor which has been analysed in production studies: the specific-word frequency (SWF). The SWF parameter allows to understand whether the grammatical class information is specified within the lexical knowledge or it is selected during post-lexical stages. We ran six lexical decision tasks employing the priming paradigm and a grammatical decision task to investigate the lexical representation of noun/verb homographs. In addition, we sought to determine the role played by the frequency of representations and the temporal activation of the grammatical class information. Our findings support the claim that these forms have independent representations for each syntactic role they can play. We interpreted these findings in the light of what we call the “Nominal Dominance” effect, which affects the lexical access of noun/verb homographs. We also discuss the relation between nominal dominance and lexical frequency.     

Recognizing cognates and interlingual homographs: Effects of code similarity in language-specific and generalized lexical decision

In four experiments, we investigated how cross-linguistic overlap in semantics, orthography, and phonology affects bilingual word recognition in different variants of the lexical decision task. Dutch-English bilinguals performed a language-specific or a generalized lexical decision task including words that are spelled and/or pronounced the same in English and in Dutch and that matched one-language control words from both languages. In Experiments 1 and 3, "false friends" with different meanings in the two languages (e.g., spot) were presented, whereas in Experiments 2 and 4 cognates with the same meanings across languages (e.g., film) were presented. The language-specific Experiments 1 and 2 replicated and qualified an earlier study (Dijkstra, Grainger, & Van Heuven, 1999). In the generalized Experiment 3, participants reacted equally quickly on Dutch-English homographs and Dutch control words, indicating that their response was based primarily on the fastest available orthographic code (i.e., Dutch). In Experiment 4, cognates were recognized faster than English and Dutch controls, suggesting coactivation of the cognates' semantics. The nonword results indicate that the bilingual rejection procedure can, to some extent, be language specific. All results are discussed within the BIA+ (bilingual interactive activation) model for bilingual word recognition.     

The recognition potential: An ERP index of lexical access

Recognition potential (RP) is a brain electrical response that appears when a subject views recognizable images of words. However, it has yet to be determined whether the processes reflected by RP are related to orthographic or to semantic analysis. This study aimed to resolve this question by studying the RP evoked by orthographically correct stimuli that were devoid of meaning. Results showed RP not only to this type of stimuli, but also to others achieving lower levels in the reading process. Strikingly, however, the RP amplitude significantly differed in parallel with the levels of the reading processes attained by the stimuli, the amplitude of the RP progressively increasing as the level approached the semantic one, which showed the highest amplitude. These results not only confirm the replicability of RP, but also its promise of potential usefulness in the study and assessment of language perception.     

Phonological processing and lexical access in aphasia

This study explored the relationship between on-line processing of phonological information and lexical access in aphasic patients. A lexical decision paradigm was used in which subjects were presented auditorily with pairs of words or word-like stimuli and were asked to make a lexical decision about the second stimulus in the pair. The initial phonemes of the first word primes, which were semantically related to the real word targets, were systematically changed by one or more than one phonetic feature, e.g., cat-dog, gat-dog, wat-dog. Each of these priming conditions was compared to an unrelated word baseline condition, e.g., nurse-dog. Previous work with normals showed that even a nonword stimulus receives a lexical interpretation if it shares a sufficient number of phonetic features with an actual word in the listener's lexicon. Results indicated a monotonically decreasing degree of facilitation as a function of phonological distortion. In contrast, fluent aphasics showed priming in all phonological distortion conditions relative to the unrelated word baseline. Nonfluent aphasics showed priming only in the undistorted, related word condition relative to the unrelated word baseline. Nevertheless, in a secondary task requiring patients to make a lexical decision on the nonword primes presented singly, all aphasics showed phonological feature sensitivity. These results suggest deficits for aphasic patients in the various processes contributing to lexical access, rather than impairments at the level of lexical organization or phonological organization.     

The bilingual L2 advantage in recognition memory

To better understand the mechanisms by which bilingual proficiency impacts memory processes, two recognition memory experiments were conducted with matched monolingual and bilingual samples. In Experiment 1, monolingual speakers of English and Spanish studied high- and low-frequency words under full attention or cognitive load conditions. In Experiment 2, Spanish–English bilingual participants studied high- and low-frequency words under full-attention conditions in each language. For both monolinguals and bilinguals, low-frequency words were better recognized than high-frequency words. The central new findings were that bilingual recognition was more accurate in the less fluent language (L2) than in the more fluent language (L1) and that bilingual L2 recognition was more accurate than monolingual recognition. The bilingual L2 advantage parallels word frequency effects in recognition and is attributed to the greater episodic distinctiveness of L2 words, relative to L1 words.     

Bilinguals in a monolingual and a bilingual speech mode: The effect on lexical access

The time course of lexical access in fluent Portuguese-English bilinguals and in English speaking monolinguals was examined during the on-line processing of spoken sentences using the phoneme-triggered lexical decision task (Blank, 1980). The bilinguals were tested in two distinct speech modes: a monolingual, English or Portuguese, speech mode, and a bilingual, code-switching, speech mode. Although the bilingual’s lexical decision response times to word targets in the monolingual speech modes were identical to those of the monolingual subjects, their response times to code-switched word targets in the bilingual mode were significantly slower. In addition, the bilinguals took longer to detect nonwords in both the monolingual and bilingual modes. These results confirm that bilinguals cannot totally deactivate their other language when in a monolingual speech mode. It is hypothesized that bilinguals search both lexicons when confronted with nonwords, even when in a totally monolingual mode, and that they search the base-language lexicon before the other lexicon when in a bilingual, code-switching, speech mode.     

Repetition blindness and bilingual memory: Token individuation for translation equivalents

The repetition blindness effect (RB) occurs when individuals are unable to recall a repeated word relative to a nonrepeated word in a sentence or string of words presented in a rapid serial visual presentation task. This effect was explored across languages (English and Spanish) in an attempt to provide evidence for RB at a conceptual level using noncognate translation equivalents (e.g.,nephew-sobrino). In the first experiment, RB was found when a word was repeated in an English sentence but not when the two repetitions were in different languages. In the second experiment, RB was found for identical repetitions in Spanish and in English using word lists. However, the crosslanguage condition produced significant facilitation in recall, suggesting that although conceptual processing had taken place, semantic overlap was not sufficient to produce RB. The results confirm Kanwisher’s (1987) token individuation hypothesis in the case of translation equivalents.     

Nonword repetition in lexical decision: Support for two opposing processes

We tested and confirmed the hypothesis that the prior presentation of nonwords in lexical decision is the net result of two opposing processes: (1) a relatively fast inhibitory process based on global familiarity; and (2) a relatively slow facilitatory process based on the retrieval of specific episodic information. In three studies, we manipulated speed-stress to influence the balance between the two processes. Experiment 1 showed item-specific improvement for repeated nonwords in a standard “respond-when-ready” lexical decision task. Experiment 2 used a 400-ms deadline procedure and showed performance for nonwords to be unaffected by up to four prior presentations. In Experiment 3 we used a signal-to-respond procedure with variable time intervals and found negative repetition priming for repeated nonwords. These results can be accounted for by dual-process models of lexical decision (e.g., Balota & Chumbley, 1984; Balota & Spieler, 1999).     

Individual differences in memory span: The contribution of rehearsal, access to lexical memory,and output speed

Rehearsal speed has traditionally been seen to be the prime determinant of individual differences in memory span. Recent studies, in the main using young children as the subject population, have suggested other contributors to span performance, notably contributions from long-term memory and forgetting and retrieval processes occurring during recall. In the current research we explore individual differences in span with respect to measures of rehearsal, output time, and access to lexical memory.We replicate standard short-term phenomena; we show that the variables that influence children's span performance influence adult performance in the same way; and we show that lexical memory access appears to be a more potent source of individual differences in span than either rehearsal speed or output factors.     

Influences of lexical tone and pitch on word recognition in bilingual infants

Infants' abilities to discriminate native and non-native phonemes have been extensively investigated in monolingual learners, demonstrating a transition from language-general to language-specific sensitivities over the first year after birth. However, these studies have mostly been limited to the study of vowels and consonants in monolingual learners. There is relatively little research on other types of phonetic segments, such as lexical tone, even though tone languages are very well represented across languages of the world. The goal of the present study is to investigate how Mandarin Chinese-English bilingual learners contend with non-phonemic pitch variation in English spoken word recognition. This is contrasted with their treatment of phonemic changes in lexical tone in Mandarin spoken word recognition. The experimental design was cross-sectional and three age-groups were sampled (7.5months, 9months and 11months). Results demonstrated limited generalization abilities at 7.5months, where infants only recognized words in English when matched in pitch and words in Mandarin that were matched in tone. At 9months, infants recognized words in Mandarin Chinese that matched in tone, but also falsely recognized words that contrasted in tone. At this age, infants also recognized English words whether they were matched or mismatched in pitch. By 11months, infants correctly recognized pitch-matched and - mismatched words in English but only recognized tonal matches in Mandarin Chinese.     

The consequences of language proficiency and difficulty of lexical access for translation performance and priming

Repetition priming was used to assess how proficiency and the ease or difficulty of lexical access influence bilingual translation. Two experiments, conducted at different universities with different Spanish–English bilingual populations and materials, showed repetition priming in word translation for same-direction and different-direction repetitions. Experiment 1, conducted in an English-dominant environment, revealed an effect of translation direction but not of direction match, whereas Experiment 2, conducted in a more balanced bilingual environment, showed an effect of direction match but not of translation direction. A combined analysis on the items common to both studies revealed that bilingual proficiency was negatively associated with response time (RT), priming, and the degree of translation asymmetry in RTs and priming. An item analysis showed that item difficulty was positively associated with RTs, priming, and the benefit of same-direction over different-direction repetition. Thus, although both participant accuracy and item accuracy are indices of learning, they have distinct effects on translation RTs and on the learning that is captured by the repetition-priming paradigm.     

Semantic processing in auditory lexical decision: Ear-of-presentation and sex differences

In this study we examined the interplay between appetitive (approach) and defensive (avoid) responses in spoken word recognition. Ninety-two right-handed participants (half women) took part in an auditory lexical decision experiment in which speech was presented to only one ear. The danger and usefulness of the word referents interacted in predicting RTs, as in previous (binaural) studies with poorer control of psycholinguistic covariates. Specifically, higher danger ratings were associated with faster RTs for words rated low on usefulness; but higher danger ratings were associated with slower RTs for words rated high on usefulness. In addition to this primary finding, men showed more lateralised performance, as indicated by significant interactions of sex and ear of presentation with word frequency, and with the animacy of the word referents. For both sexes, word frequency had a stronger effect on accuracy for speech presented to the right ear. Finally, men's but not women's RTs were related to the danger dimension. This last finding provides an intriguing avenue for future research in the area of sex differences and emotion.     

The generation effect with homographs: Evidence for postgeneration processing

The generation effect is the phenomenon in which words are remembered better when generated than when read. These experiments test the possibility that at least one consequence of generating is enhanced semantic processing. Homographs were used as targets, presented with rhymes in Experiment 1 so as not to bias meaning, and with synonyms in Experiment 2 to bias one meaning of each homograph. In beth experiments, extralist synonym cues were provided at recall. In Experiment 1 a generation effect was obtained when the retrieval cues biased the dominant meaning of the homograph (determined from free association norms), whereas in Experiment 2 a generation effect was found when the retrieval cues biased the same meaning that was biased during study. In neither experiment was a generation effect obtained with retrieval cues that biased the other meaning of each homograph. These results indicate that the generation effect is dependent upon the compatibility of the semantic processing conducted at study and test. Since it is impossible to process the meaning of a homograph when generating it from a rhyme cue, the meaning of the homograph could only have been processed after the word had been generated. The finding in Experiment 1 that a generation effect was obtained with rhymes when semantic retrieval cues were provided demonstrates that the enhancement properties associated with generation are not restricted to the information used to guide the generation process. This finding also indicates that one locus of the generation effect is in the processing that occurs after the word has been generated.     

Joint effects of semantic priming and repetition in a lexical decision task: Implications for a model of lexical access

An experiment is reported which showed that in a lexical decision task semantic priming by a related preceding word and repetition of target words produce additive effects on decision latency. Previous models of lexical access and modifications of them are discussed, and it is argued that some such models predict an interaction of priming and repetition, while others are insufficiently precise to make a prediction. It is suggested that the generality of effects across tasks requiring lexical access must be established and the components of complex effects must be separated before an adequate model can be devised to account for the data.     

Components of activation: repetition and priming effects in lexical decision and recognition

Activation decay functions were examined in two different tasks: lexical decision and word recognition. Activation (amount of facilitation) was measured both for item repetition and for priming between newly learned associates. Results indicate that there are at least three different components of activation: a short-term component that decays with one or two intervening items and that appears to be common to priming and repetition; an intermediate component for repetition in recognition; and a long-term component for repetition.     

Semantic access in number word translation: the role of crosslingual lexical similarity

The revised hierarchical model of bilingualism (e.g., Kroll & Stewart, 1994) assumes that second language (L2) words primarily access semantics through their first language (L1) translation equivalents. Consequently, backward translation from L2 to L1 should not imply semantic access but occurs through lexical wordform associations. However, recent research with Dutch-French bilinguals showed that both backward and forward translation of number words yields a semantic number magnitude effect (Duyck & Brysbaert, 2004), providing evidence for strong form-to-meaning mappings of L2 number words. In two number-word translation experiments with Dutch-English-German trilinguals, the present study investigated whether semantic access in L1-L2 and L1-L3 number-word translation depends on lexical similarity of the languages involved. We found that backward translation from these more similar language pairs to L1 still yields a semantic magnitude effect, whereas forward translation does not, in contrast with the Dutch-French results of Duyck and Brysbaert (2004). We argue against a dual route model of word translation and suggest that the degree of semantic activation in translation depends on lexical form overlap between translation equivalents.     

Priming effects on lexical access and decision processes: A signal-detection analysis

Summary Signal-detection methodology was employed to examine the assumption that in a lexical-decision task context effects are primarily the result of post-access processes. Experiment 1, in which prime-relatedness was varied within subjects, found changes in target sensitivity (d) without corresponding changes in the response criterion. This outcome was interpreted as evidence that prior context facilitates lexical access, whereas post-access contributions remain constant across conditions. When prime-relatedness was varied between subjects in Experiment 2, the lexical-decision task showed differing context effects on access processes as well as on post-access processes. It was concluded that subjects adopt a single response criterion suited to maximize task performance. The particular response criterion adopted is a function of the stimulus set rather than a function of the relationship between prime and target on any single trial. Finally, it was concluded that post-access strategies alone are insufficient to account for context effects obtained when typical lexical-decision-task procedures are used, or to account for the magnitude of the differences obtained between the present experiments.     

Attention and implicit memory in the category-verification and lexical decision tasks

Prior research on implicit memory appeared to support 3 generalizations: Conceptual tests are affected by divided attention, perceptual tasks are affected by certain divided-attention manipulations, and all types of priming are affected by selective attention. These generalizations are challenged in experiments using the implicit tests of category verification and lexical decision. First, both tasks were unaffected by divided-attention tasks known to impact other priming tasks. Second, both tasks were unaffected by a manipulation of selective attention in which colored words were either named or their colors identified. Thus, category verification, unlike other conceptual tasks, appears unaffected by divided attention, and some selective-attention tasks, and lexical decision, unlike other perceptual tasks, appears unaffected by a difficult divided-attention task and some selective-attention tasks. Finally, both tasks were affected by a selective-attention task in which attention was manipulated across objects (rather than within objects), indicating some susceptibility to selective attention. The results contradict an analysis on the basis of the conceptual-perceptual distinction and other more specific hypotheses but are consistent with the distinction between production and identification priming.     

Processing interactions and lexical access during word recognition in continuous speech

The interactions, during word-recognition in continuous speech, between the bottom-up analyses of the input and different forms of internally generated top-down constraint, were investigated using a shadowing task and a mispronunciation detection task (in the detection task the subject saw a text of the original passage as he listened to it). The listener's dependence on bottom-up analyses in the shadowing task, as measured by the number of fluent restorations of mispronounced words, was found to vary as a function of the syllable position of the mispronunciation within the word and of the contextual constraints on the word as a whole. In the detection task only syllable position effects were obtained. The results, discussed in conjunction with earlier research, were found to be inconsistent with either the logogen model of word-recognition or an autonomous search model. Instead, an active direct access model is proposed, in which top-down processing constraints interact directly with bottom-up information to produce the primary lexical interpretation of the acoustic-phonetic input.