The word frequency effect in lexical decision: Finding a frequency-based component

Subjects making lexical decisions are reliably faster in responding to high-frequency words than to low-frequency words. This is known as the word frequency effect. We wished to demonstrate that some portion of this effect was due to frequency differences between words rather than to other dimensions correlated with word frequency. Three groups of subjects (10 engineers, 10 nurses, and I0 law students) made lexical decisions about 720 items, half words and half nonwords, from six different categories (engineering, medical, low-frequency nontechnical, medium-frequency nontechnical, and two groups of high-frequency nontechnical). Results of two analyses of variance revealed a crossover interaction such that engineers were faster in responding to engineering words than to medical words, whereas nurses were faster in responding to medical words than to engineering words. The engineering and medical words were equally long and equally infrequent by standard word counts. We take this as support for a frequency-based component in the word frequency effect. The practical implications of this research for estimating the readability of technical text are discussed.     

Cognitive effort and the word frequency effect in recognition and lexical decision

Cognitive effort requirements for high and low frequency words were assessed during study for a recognition test and during the performance of a lexical decision task. Recognition for these words was tested following each task. Low frequency words received greater effort than high frequency words during study for recognition, and these words were subsequently recognized better than high frequency words. Cognitive effort requirements during performance of an incidental lexical decision task were similar to those during study for recognition. Moreover, recognition performance following the lexical decision task resembled performance following a recognition expectancy. Overall, the results indicate that low frequency words require more extensive processing than high frequency words and that this difference in processing may be a factor in recognition word frequency effects.     

Aphasic performance on a lexical decision task: multiple meanings and word frequency

The lexical access of words varying in the number of meanings and frequency of occurrence was examined in fluent and nonfluent aphasic individuals and a control group of non-brain-damaged adults, using a lexical decision task. Fluent aphasic subjects performed similarly to nonfluent aphasic and normal subjects, showing that words with a high number of meanings and with a high frequency of occurrence were recognized as real words faster than words with few meanings or a low frequency of occurrence. While previous research has demonstrated that the number of meanings associated with a word exerts a powerful influence on the internal lexicon of normals, the results of this study suggest that brain damage resulting in aphasia does not disrupt this semantic organization.     

Modeling lexical decision and word naming as a retrieval process.

We argue that rule-like phenomena in naming and lexical decision reflect the collapsing of information that occurs during retrieval from the lexicon, and that complex patterns in performance reflect the pattern of correlation that exists in the reader's lexicon rather than mapping rules wired into, or learned by, the processing apparatus. By using a lexicon built to scale, we show that simple retrieval operations applied to a large corpus of words correctly predict an interaction of word frequency by spelling-to-sound regularity in naming, a frequency main effect in lexical decision, sensitivity to orthographically defined syllable-like structures in lexical decision, and an interaction of number of syllables with word frequency in naming.     

The word frequency effect in first- and second-language word recognition: A lexical entrenchment account

We investigate the origin of differences in the word frequency effect between native speakers and second-language speakers. In a large-scale analysis of English word identification times we find that group-level differences are fully accounted for by the individual language proficiency scores. Furthermore, exactly the same quantitative relation between word frequency and proficiency is found for monolinguals and three different bilingual populations (Dutch–English, French–English, and German–English). We conclude that the larger frequency effects for second-language processing than for native-language processing can be explained by within-language characteristics and thus need not be the consequence of “being bilingual” (i.e., a qualitative difference). More specifically, we argue that language proficiency increases lexical entrenchment, which leads to a reduced frequency effect, irrespective of bilingualism, language dominance, and language similarity.     

Neighborhood frequency effects in visual word recognition: a comparison of lexical decision and masked identification latencies

Recent research suggests that the time to recognize a visually presented word may be a function of the frequencies of orthographically similar words. More precisely, recognition latencies and errors appear to increase significantly as soon as the stimulus word is orthographically similar to at least one other higher frequency word. This phenomenon, referred to as the neighborhood frequency effect, was subjected to further experimental testing, using a larger selection of words of varying frequency and length, and using a new experimental technique that proved to be extremely sensitive to such effects. The results provide additional support for earlier observations of neighborhood frequency effects. It is also demonstrated that clear word-frequency effects do obtain when neighborhood frequency is held constant. The results support activation-based accounts of the word-recognition process.     

Contextual diversity, not word frequency, determines word-naming and lexical decision times

Word frequency is an important predictor of word-naming and lexical decision times. It is, however, confounded with contextual diversity, the number of contexts in which a word has been seen. In a study using a normative, corpus-based measure of contextual diversity, word-frequency effects were eliminated when effects of contextual diversity were taken into account (but not vice versa) across three naming and three lexical decision data sets; the same pattern of results was obtained regardless of which of three corpora was used to derive the frequency and contextual-diversity values. The results are incompatible with existing models of visual word recognition, which attribute frequency effects directly to frequency, and are particularly problematic for accounts in which frequency effects reflect learning. We argue that the results reflect the importance of likely need in memory processes, and that the continuity between reading and memory suggests using principles from memory research to inform theories of reading.     

The attentional control of lexical processing pathways: Reversing the word frequency effect

In two experiments, we investigated the influence of word frequency in speeded word naming and in a relatively novel regularization task in which participants were required to pronounce words on the basis of spelling-to-sound correspondences instead of giving their normal pronunciations (e.g., pronounce pint so that it rhymes with hint). Participants were presented high- and low-frequency regular words and exception words, along with a set of nonwords. The results indicated that there was a normal word frequency effect (i.e., high-frequency words faster than low-frequency words) in the standard speeded naming task, whereas, for the regularization task, the word frequency effect was reversed for regular words, even though the regular words were pronounced in an identical fashion in both the normal naming and the regularization tasks. This reversal of the word frequency effect was not obtained for the exception words. The discussion focuses on the implication of these results for attentional control models of lexical processing.     

Additive and interactive effects of word frequency and masked repetition in the lexical decision task

In previous studies, additive effects of masked repetition and word frequency on lexical decision latency have been reported. This additive pattern was replicated in Experiment 1 with the use of lowfrequency words (range, 1–7 per million) selected at random. In contrast, in Experiment 2, in which low-frequency words known to be familiar to the subjects were used, the masked repetition priming effect was greater for low-frequency than for high-frequency words. It is suggested that the absence of an interaction between masked repetition and frequency observed in previous studies and in the present Experiment 1 was due to the fact that very-low-frequency words often have an unstable representation in the subjects’ lexicon and, consequently, sometimes fail to produce repetition priming effects in full.     

The frequency effect for pseudowords in the lexical decision task

Four experiments were designed to investigate whether the frequency of words used to create pseudowords plays an important role in lexical decision. Computational models of the lexical decision task (e.g., the dual route cascaded model and the multiple read-out model) predict that latencies to low-frequency pseudowords should be faster than latencies to high-frequency pseudowords. Consistent with this prediction, results showed that when the pseudowords were created by replacing one internal letter of the base word (Experiments 1 and 3), high-frequency pseudowords yielded slower latencies than low-frequency pseudowords. However, this effect occurred only in the leading edge of the response time (RT) distributions. When the pseudowords were created by transposing two adjacent internal letters (Experiment 2), high-frequency pseudowords produced slower latencies in the leading edge and in the bulk of the RT distributions. These results suggest that transposed-letter pseudowords may be more similar to their base words than replacement-letter pseudowords. Finally, when participants performed a go/no-go lexical decision task with one-letter different pseudowords (Experiment 4), high-frequency pseudowords yielded substantially faster latencies than low-frequency pseudowords, which suggests that the lexical entries of high-frequency words can be verified earlier than the lexical entries of low-frequency words. The implications of these results for models of word recognition and lexical decision are discussed.     

Word-context effects in word naming and lexical decision

Stanovich and West (1983; West and Stanovich, 1982) demonstrated that lexical decisions to target words preceded by incongruous sentence contexts are inhibited more by these contexts than are naming responses to the same target words. They argued that this difference between the two tasks was due to post-lexical processing at the message level that is effective only in the lexical-decision task. The operations of the mechanism thought to underlie this post-lexical effect also predict that, under certain circumstances, the processing of target words congruous with the sentence context should be facilitated more in lexical decision than in naming. The present naming study together with an earlier lexical-decision study tested and confirmed this prediction for word targets following word contexts. The stimulus-onset asynchrony of context word and target word was also varied. This manipulation clearly affected the magnitude of facilitation, indicating that context-induced attentional processing can facilitate lexical access in word-context studies.     

Dissociating the influence of familiarity and meaningfulness from word frequency in naming and lexical decision performance

Performance in two experiments was compared on a list of words of high and low frequency in which familiarity/meaningfulness (FM) was balanced and on a list of high- and low-frequency words in which FM was confounded with frequency (i.e., high frequency--high familiarity vs. low frequency--low familiarity). Both repetition and task (lexical decision and naming) were investigated. In the lexical decision task of Experiment 1, both frequency and repetition effects were larger in the list with FM confounded than in the list with FM matched. In the naming task, frequency and repetition effects and their interaction were significant, but there was no influence of FM list context. In Experiment 2, in which the repetitions occurred across blocks, as opposed to randomly intermixed within a list, similar results were found; however, there was no interaction between list and repetition. The results suggest that an evaluation of items in terms of their meaning and familiarity explains a large part of the variance, only in lexical decision. These dimensions may be cued both by subjective feelings of familiarity and the extent to which semantic information is available and by episodic traces due to recent encounters with the item.     

Effects of word frequency and spelling-to-sound regularity in naming with and without preceding lexical decision

The effects of word frequency and spelling-to-sound regularity were examined using standard naming, standard lexical-decision, go/no-go naming, and go/no-go lexical-decision tasks. In both the standard and go/no-go naming tasks, tasks requiring phonological coding, a significant Frequency x Regularity interaction was observed. That is, the regularity effect was limited to low-frequency words. In the standard and go/no-go lexical-decision tasks, tasks not requiring phonological coding, no Frequency x Regularity interaction was observed. These results indicate not only that the Frequency x Regularity interaction is a product of phonological coding processes but also that these processes are similar in the standard and go/no-go naming tasks. Results are discussed in terms of the dual-route and the parallel distributed processing frameworks.     

Contrasting effects of age of acquisition and word frequency on auditory and visual lexical decision

In four experiments, we examined the effects of frequency and age of acquisition on auditory and visual lexical decision. Word frequency affected visual, but not auditory, lexical decision speed (Experiments 1 and 3). Age of acquisition affected lexical decision speed in both modalities (Experiments 2 and 4). We suggest that previous reports of effects of frequency on auditory lexical decision may be due to a confounding of frequency with age of acquisition, and we discuss the implications of these findings for theories of auditory and visual word recognition.     

Age of acquisition, word frequency, and the role of phonology in the lexical decision task

In five experiments, we examined the respective roles of word age of acquisition (AoA) and frequency in the lexical decision task. The two variables were manipulated orthogonally (while controlling for concreteness and length) in fully factorial designs. Experiment 1 was a conventional lexical decision task, and Experiments 2-5 involved various attempts to interfere with reliance upon phonology. In Experiment 2, only orthographically illegal nonwords were used; in Experiment 3, pseudohomophone nonwords; in Experiment 4, articulatory suppression by the recitation of a nursery rhyme; and in Experiment 5, articulatory suppression by the repetition of a single word. The same basic pattern of results was observed in all experiments: There were main effects of both AoA and frequency, which interacted in such a way that the AoA effect was larger for low- than for high-frequency words. Although the AoA effect was reduced by manipulations intended to interfere with phonological processing, the manipulations did not eliminate the effect. The results are discussed in terms of current models of reading in which it is proposed that AoA has its primary effect on the retrieval of lexical phonology, which appears to be consulted automatically in the lexical decision task.     

Pseudohomophone effects in lexical decision: still a challenge for current word recognition models.

Computational models that implement a serial mechanism of phonological assembly predict interactions between the size of the pseudohomophone (PsH) effect and stimulus length. Models with frequency-sensitive word representations predict baseword frequency effects. These predictions were tested in a lexical-decision task. The results showed constant PsH effects across different word lengths (in favor of parallel phonological activation) and baseword frequency effects (in favor of frequency-sensitive representations). However, the baseword frequency effect was opposite of what the models predicted. This result is most easily accommodated by models that assume an orthographic verification mechanism. The plausibility of such a mechanism was further supported by the results of 2 additional experiments investigating the effects of response speed and spelling probability (feedback consistency) on the size of the PsH effect.     

Long-term priming of neighbours biases the word recognition process: evidence from a lexical decision task.

The role of orthographically similar words (i.e., neighbours) in the word recognition process has been studied extensively using short-term priming paradigms (e.g., Colombo, 1986). Here we demonstrate that long-term effects of neighbour priming can also be obtained. Experiment 1 showed that prior study of a neighbour (e.g., TANGO) increased later lexical decision performance for similar words (e.g., MANGO), but decreased performance for similar pseudowords (e.g., LANGO). Experiment 2 replicated this bias effect and showed that the increase in lexical decision performance due to neighbour priming is selectively due to words from a relatively sparse neighbourhood. Explanations of the bias effect in terms of lexical activation and episodic memory retrieval are discussed.     

The effect of word length on lexical decision in dyslexic and normal reading children

In the present study, the effect of word length on lexical decision in dyslexic and normal reading children was investigated. Dyslexics of 10-years old, chronological age controls, and reading age controls read words and pseudowords consisting of 3 to 6 letters in a lexical decision task. Length effects were much stronger in dyslexics and reading age controls than in chronological age controls. These results support the contention that dyslexics continue to rely on a predominantly sub-lexical reading procedure, whereas for normal readers the contribution of a lexical reading procedure increases. The relevance of the findings for current computational models of reading is discussed.     

Modeling lexical decision: the form of frequency and diversity effects

What is the root cause of word frequency effects on lexical decision times? W. S. Murray and K. I. Forster (2004) argued that such effects are linear in rank frequency, consistent with a serial search model of lexical access. In this article, the authors (a) describe a method of testing models of such effects that takes into account the possibility of parametric overfitting; (b) illustrate the effect of corpus choice on estimates of rank frequency; (c) give derivations of nine functional forms as predictions of models of lexical decision; (d) detail the assessment of these models and the rank model against existing data regarding the functional form of frequency effects; and (e) report further assessments using contextual diversity, a factor confounded with word frequency. The relationship between the occurrence distribution of words and lexical decision latencies to those words does not appear compatible with the rank hypothesis, undermining the case for serial search models of lexical access. Three transformations of contextual diversity based on extensions of instance models do, however, remain as plausible explanations of the effect.     

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.