Hemispheric differences in indexical specificity effects in spoken word recognition

Variability in talker identity, one type of indexical variation, has demonstrable effects on the speed and accuracy of spoken word recognition. Furthermore, neuropsychological evidence suggests that indexical and linguistic information may be represented and processed differently in the 2 cerebral hemispheres, and is consistent with findings from the visual domain. For example, in visual word recognition, changes in font affect processing differently depending on which hemisphere initially processes the input. The present study examined whether hemispheric differences exist in spoken language as well. In 4 long-term repetition-priming experiments, the authors examined responses to stimuli that were primed by stimuli that matched or mismatched in talker identity. The results demonstrate that indexical variability can affect participants' perception of spoken words differently in the 2 hemispheres.     

The gender-marking effect in spoken word recognition

In this paper we examine whether the recognition of a spoken noun is affected by the gender marking—masculine or feminine—that is carried by a preceding word. In the first of two experiments, the gating paradigm was used to study the access of French nouns that were preceded by an appropriate gender marking, carried by an article, or preceded by no gender marking. In the second experiment, subjects were asked to make a lexical decision on the same material. A very strong facilitatory effect was found in both cases. The origin of the gender-marking effect is discussed, as well as the level of processing involved—lexical or syntactic.     

Examining the time course of indexical specificity effects in spoken word recognition

Variability in talker identity and speaking rate, commonly referred to as indexical variation, has demonstrable effects on the speed and accuracy of spoken word recognition. The present study examines the time course of indexical specificity effects to evaluate the hypothesis that such effects occur relatively late in the perceptual processing of spoken words. In 3 long-term repetition priming experiments, the authors examined reaction times to targets that were primed by stimuli that matched or mismatched on the indexical variable of interest (either talker identity or speaking rate). Each experiment was designed to manipulate the speed with which participants processed the stimuli. The results demonstrate that indexical variability affects participants' perception of spoken words only when processing is relatively slow and effortful.     

Famous talker effects in spoken word recognition

Previous work has demonstrated that talker-specific representations affect spoken word recognition relatively late during processing. However, participants in these studies were listening to unfamiliar talkers. In the present research, we used a long-term repetition-priming paradigm and a speeded-shadowing task and presented listeners with famous talkers. In Experiment 1, half the words were spoken by Barack Obama, and half by Hillary Clinton. Reaction times (RTs) to repeated words were shorter than those to unprimed words only when repeated by the same talker. However, in Experiment 2, using nonfamous talkers, RTs to repeated words were shorter than those to unprimed words both when repeated by the same talker and when repeated by a different talker. Taken together, the results demonstrate that talker-specific details can affect the perception of spoken words relatively early during processing when words are spoken by famous talkers.     

Phonological priming in spoken word recognition: Task effects

In two experiments, we examined the role of phonological relatedness between spoken items using both the lexical decision task and the shadowing task. In Experiment 1, words were used as primes and overlaps of zero (control), one, two, or all four or five (repetition) phonemes were compared. Except for the repetition conditions, in which facilitation was found, phonological overlap resulted in interference on word responses. These effects occurred in both tasks but were larger in lexical decision than in shadowing. The effects that were evident in shadowing can be attributed to an attentional mechanism linked to the subjects' expectancies of repetitions. The extra effects obtained in lexical decision can be interpreted by taking into account both activation of the response corresponding to the prime's lexical status and postlexical processes that check for phonological congruency between prime and target. In Experiment 2, some modifications were introduced to prevent the involvement of strategic factors, and pseudowords were used as primes. No effect at all was observed in shadowing, whereas in lexical decision interference effects occurred, which is consistent with the hypothesis that lexical decision may be negatively affected by finding a phonological discrepancy at the same time as the primed response is reactivated. Neither experiment provided evidence for the occurrence of phonological priming in the perceptual processing of words.     

The gender marking effect in spoken word recognition: The case of bilinguals

It has been known for some time that the recognition of a noun is affected by the gender marking, such as masculine or feminine, that is carried by a preceding word. In this study, we used auditory naming to examine how early and late English-French bilinguals react to gender marking when processing French. The early bilinguals showed clear facilitation and inhibition effects, but the late bilinguals were totally insensitive to gender marking, whether congruent or incongruent. The results are discussed in terms of current accounts of gender processing as well as age of acquisition and regular use of the gender-marking language.     

Immediate effects of form-class constraints on spoken word recognition

In many domains of cognitive processing there is strong support for bottom-up priority and delayed top-down (contextual) integration. We ask whether this applies to supra-lexical context that could potentially constrain lexical access. Previous findings of early context integration in word recognition have typically used constraints that can be linked to pair-wise conceptual relations between words. Using an artificial lexicon, we found immediate integration of syntactic expectations based on pragmatic constraints linked to syntactic categories rather than words: phonologically similar "nouns" and "adjectives" did not compete when a combination of syntactic and visual information strongly predicted form class. These results suggest that predictive context is integrated continuously, and that previous findings supporting delayed context integration stem from weak contexts rather than delayed integration.     

Interference of spoken word recognition through phonological priming from visual objects and printed words

Three cross-modal priming experiments examined the influence of preexposure to pictures and printed words on the speed of spoken word recognition. Targets for auditory lexical decision were spoken Dutch words and nonwords, presented in isolation (Experiments 1 and 2) or after a short phrase (Experiment 3). Auditory stimuli were preceded by primes, which were pictures (Experiments 1 and 3) or those pictures’ printed names (Experiment 2). Prime–target pairs were phonologically onset related (e.g., pijl–pijn, arrow–pain), were from the same semantic category (e.g., pijl–zwaard, arrow–sword), or were unrelated on both dimensions. Phonological interference and semantic facilitation were observed in all experiments. Priming magnitude was similar for pictures and printed words and did not vary with picture viewing time or number of pictures in the display (either one or four). These effects arose even though participants were not explicitly instructed to name the pictures and where strategic naming would interfere with lexical decision making. This suggests that, by default, processing of related pictures and printed words influences how quickly we recognize spoken words.     

Visual attention shift to printed words during spoken word recognition in Chinese: The role of phonological information

The aim of this study was to investigate the extent to which phonological information mediates the visual attention shift to printed Chinese words in spoken word recognition by using an eye-movement technique with a printed-word paradigm. In this paradigm, participants are visually presented with four printed words on a computer screen, which include a target word, a phonological competitor, and two distractors. Participants are then required to select the target word using a computer mouse, and the eye movements are recorded. In Experiment 1, phonological information was manipulated at the full-phonological overlap; in Experiment 2, phonological information at the partial-phonological overlap was manipulated; and in Experiment 3, the phonological competitors were manipulated to share either fulloverlap or partial-overlap with targets directly. Results of the three experiments showed that the phonological competitor effects were observed at both the full-phonological overlap and partial-phonological overlap conditions. That is, phonological competitors attracted more fixations than distractors, which suggested that phonological information mediates the visual attention shift during spoken word recognition. More importantly, we found that the mediating role of phonological information varies as a function of the phonological similarity between target words and phonological competitors.     

Frequency effects in spoken and visual word recognition: evidence from dual-task methodologies

The authors report 3 dual-task experiments concerning the locus of frequency effects in word recognition. In all experiments, Task 1 entailed a simple perceptual choice and Task 2 involved lexical decision. In Experiment 1, an underadditive effect of word frequency arose for spoken words. Experiment 2 also showed underadditivity for visual lexical decision. It was concluded that word frequency exerts an influence prior to any dual-task bottleneck. A related finding in similar dual-task experiments is Task 2 response postponement at short stimulus onset asynchronies. This was explored in Experiment 3, and it was shown that response postponement was equivalent for both spoken and visual word recognition. These results imply that frequency-sensitive processes operate early and automatically.     

The nature of phoneme representation in spoken word recognition

Four experiments used the psychological refractory period logic to examine whether integration of multiple sources of phonemic information has a decisional locus. All experiments made use of a dual-task paradigm in which participants made forced-choice color categorization (Task 1) and phoneme categorization (Task 2) decisions at varying stimulus onset asynchronies. In Experiment 1, Task 2 difficulty was manipulated using words containing matching or mismatching coarticulatory cues to the final consonant. The results showed that difficulty and onset asynchrony combined in an underadditive way, suggesting that the phonemic mismatch was resolved prior to a central decisional bottleneck. Similar results were found in Experiment 2 using nonwords. In Experiment 3, the manipulation of task difficulty involved lexical status, which once again revealed an underadditive pattern of response times. Finally, Experiment 4 compared this prebottleneck variable with a decisional variable: response key bias. The latter showed an additive pattern of responses. The experiments show that resolution of phonemic ambiguity can take advantage of cognitive slack time at short asynchronies, indicating that phonemic integration takes place at a relatively early stage of spoken word recognition.     

Orthographic influences in spoken word recognition: The consistency effect in semantic and gender categorization tasks

According to current models, spoken word recognition is driven by the phonological properties of the speech signal. However, several studies have suggested that orthographic information also influences recognition in adult listeners. In particular, it has been repeatedly shown that, in the lexical decision task, words that include rimes with inconsistent spellings (e.g., /-ip/ spelled -eap or -eep) are disadvantaged, as compared with words with consistent rime spelling. In the present study, we explored whether the orthographic consistency effect extends to tasks requiring people to process words beyond simple lexical access. Two different tasks were used: semantic and gender categorization. Both tasks produced reliable consistency effects. The data are discussed as suggesting that orthographic codes are activated during word recognition, or that the organization of phonological representations of words is affected by orthography during literacy acquisition.     

The effect of lexical frequency on spoken word recognition in young and older listeners

When identifying spoken words, older listeners may have difficulty resolving lexical competition or may place a greater weight on factors like lexical frequency. To obtain information about age differences in the time course of spoken word recognition, young and older adults' eye movements were monitored as they followed spoken instructions to click on objects displayed on a computer screen. Older listeners were more likely than younger listeners to fixate high-frequency displayed phonological competitors. However, degradation of auditory quality in younger listeners does not reproduce this result. These data are most consistent with an increased role for lexical frequency with age.     

The interaction of meaning and sound in spoken word recognition

Models of spoken word recognition vary in the ways in which they capture the relationship between speech input and meaning. Modular accounts prohibit a word’s meaning from affecting the computation of its form-based representation, whereas interactive models allow activation at the semantic level to affect phonological processing. We tested these competing hypotheses by manipulating word familiarity and imageability, using lexical decision and repetition tasks. Responses to high-imageability words were significantly faster than those to low-imageability words. Repetition latencies were also analyzed as a function of cohort variables, revealing a significant imageability effect only for words that were members of large cohorts, suggesting that when the mapping from phonology to semantics is difficult, semantic information can help the discrimination process. Thus, these data support interactive models of spoken word recognition.     

Cross-modal source information and spoken word recognition

In a cross-modal matching task, participants were asked to match visual and auditory displays of speech based on the identity of the speaker. The present investigation used this task with acoustically transformed speech to examine the properties of sound that can convey cross-modal information. Word recognition performance was also measured under the same transformations. The authors found that cross-modal matching was only possible under transformations that preserved the relative spectral and temporal patterns of formant frequencies. In addition, cross-modal matching was only possible under the same conditions that yielded robust word recognition performance. The results are consistent with the hypothesis that acoustic and optical displays of speech simultaneously carry articulatory information about both the underlying linguistic message and indexical properties of the talker.     

The growth of lexical constraints on spoken word recognition

In this study, we examined the influence of various sources of constraint on spoken word recognition in a mispronunciation-detection task. Five- and 8-year-olds and adults were presented with words (intact or with word-initial or noninitial errors) from three different age-of-acquisition categories. "Intact" and "mispronounced" responses were collected for isolated words with or without a picture referent (Experiment 1) and for words in constraining or unconstraining sentences (Experiment 2). Some evidence for differential attention to word-initial as opposed to noninitial acoustic-phonetic information (and thus the influence of sequential lexical constraints on recognition) was apparent in young children's and adults' response criteria and in older children's and adults' reaction times. A more marked finding, however, was the variation in subjects' performance, according to several measures, with age and lexical familiarity (defined according to adults' subjective age-of-acquisition estimates). Children's strategies for responding to familiar and unfamiliar words in different contexts are discussed.     

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

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

Grammatical gender in spoken word recognition in German

The role of grammatical gender for auditory word recognition in German was investigated in three experiments and two sets of corpus analyses. In the corpus analyses, gender information reduced the lexical search space as well as the amount of input needed to uniquely identify a word. To test whether this holds for on-line processing, two auditory lexical decision experiments (Experiments 1 and 3) were conducted using valid, invalid, or noise-masked articles as primes. Clear gender-priming effects were obtained in both experiments. Experiment 2 used phoneme monitoring with words and with pseudowords deviating from base words in one or more phonological features. Contrary to the lexical decision latencies, phoneme-monitoring latencies showed no influence of gender but did show similarity mismatch effects. We argue that gender information is not utilized early during word recognition. Rather, the presence of a valid article increases the initial familiarity of a word, facilitating subsequent responses.     

Context and spoken word recognition in a novel lexicon

Three eye movement studies with novel lexicons investigated the role of semantic context in spoken word recognition, contrasting 3 models: restrictive access, access-selection, and continuous integration. Actions directed at novel shapes caused changes in motion (e.g., looming, spinning) or state (e.g., color, texture). Across the experiments, novel names for the actions and the shapes varied in frequency, cohort density, and whether the cohorts referred to actions (Experiment 1) or shapes with action-congruent or action-incongruent affordances (Experiments 2 and 3). Experiment 1 demonstrated effects of frequency and cohort competition from both displayed and non-displayed competitors. In Experiment 2, a biasing context induced an increase in anticipatory eye movements to congruent referents and reduced the probability of looks to incongruent cohorts, without the delay predicted by access-selection models. In Experiment 3, context did not reduce competition from non-displayed incompatible neighbors as predicted by restrictive access models. The authors conclude that the results are most consistent with continuous integration models.