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.     

Influence of neighborhood size and exposure duration on visual-word recognition: evidence with the yes/no and the go/no-go lexical decision tasks

We present two experiments in which we measured lexical decision latencies and errors to words with few or many orthographic neighbors (ie., Coltheart's N). The main goal of the study was to examine whether or not the neighborhood size effect in a lexical decision task could be affected by the exposure duration of the stimulus item (unlimited vs. limited time exposure, 150 msec plus a backward mask) and the type of decision involved in the task (yes/no vs. go/no-go lexical decision tasks). In the yes/no task, the results showed a facilitative neighborhood size effect for low frequency that did not interact with exposure duration (Experiment 1). In contrast, in the go/no-go task (in this task, participants are instructed to respond as quickly as they can when a word is presented and not to respond if a nonword is presented), the neighborhood size effect for low-frequency words (and for nonwords) was greater under limited viewing time (Experiment 2). In addition, the word frequency effect was greater in the go/no-go task than in the yes/no task, replicating Hino and Lupker (1998, 2000). The results were interpreted in terms of the interaction of decision and lexical factors in visual-word recognition.     

Is the go/no-go lexical decision task preferable to the yes/no task with developing readers?

The lexical decision task is probably the most common laboratory visual word identification task together with the naming task. In the usual setup, participants need to press the “yes” button when the stimulus is a word and the “no” button when the stimulus is not a word. A number of studies have employed this task with developing readers; however, error rates and/or response times tend to be quite high. One way to make the task easier for young readers is by employing a go/no-go procedure: “If word, press ‘yes’; if not, refrain from responding.” Here we conducted a lexical decision experiment that systematically compared the yes/no and go/no-go variants of the lexical decision task with developing readers (second- and fourth-grade children). Results showed that (a) error rates for words and nonwords were much lower in the go/no-go task than in the yes/no task, (b) lexical decision times were substantially faster in the go/no-go task, and (c) there was less variability in the latency data of the go/no-go task for high-frequency words. Thus, the go/no-go lexical decision task is preferable to the “standard” yes/no task when conducting experiments with developing readers.     

Do transposed-letter similarity effects occur at a prelexical phonological level?

Nonwords created by transposing two letters (e.g., RELOVUTION) are very effective at activating the lexical representation of their base words (Perea & Lupker, 2004). In the present study, we examined whether the nature of transposed-letter (TL) similarity effects was purely orthographic or whether it could also have a phonological component. Specifically, we examined transposed-letter similarity effects for nonwords created by transposing two nonadjacent letters (e.g., relovución-REVOLUCION) in a masked form priming experiment using the lexical decision task (Experiment 1). The controls were (a) a pseudohomophone of the transposed-letter prime (relobución-REVOLUCION; note that B and V are pronounced as /b/ in Spanish) or (b) an orthographic control (relodución-REVOLUCION). Results showed a similar advantage of the TL nonword condition over the phonological and the orthographic control conditions. Experiment 2 showed a masked phonological priming effect when the letter positions in the prime were in the right order. In a third experiment, using a single-presentation lexical decision task, TL nonwords produced longer latencies than the orthographic and phonological controls, whereas there was only a small phonological effect restricted to the error data. These results suggest that TL similarity effects are orthographic--rather than phonological--in nature.     

Previewing the neighborhood: the role of orthographic neighbors as parafoveal previews in reading

In 2 experiments, a boundary technique was used with parafoveal previews that were identical to a target (e.g., sleet), a word orthographic neighbor (sweet), or an orthographically matched nonword (speet). In Experiment 1, low-frequency words in orthographic pairs were targets, and high-frequency words were previews. In Experiment 2, the roles were reversed. In Experiment 1, neighbor words provided as much preview benefit as identical words and greater benefit than nonwords, whereas in Experiment 2, neighbor words provided no greater preview benefit than nonwords. These results indicate that the frequency of a preview influences the extraction of letter information without setting up appreciable competition between previews and targets. This is consistent with a model of word recognition in which early stages largely depend on excitation of letter information, and competition between lexical candidates becomes important only in later stages.     

Reading development in agglutinative languages: Evidence from beginning,intermediate, and adult Basque readers

Do typological properties of language, such as agglutination (i.e., the morphological process of adding affixes to the lexeme of a word), have an impact on the development of visual word recognition? To answer this question, we carried out an experiment in which beginning, intermediate, and adult Basque readers (n = 32 each, average age = 7, 11, and 22 years, respectively) needed to read correctly versus incorrectly inflected words embedded in sentences. Half of the targets contained high-frequency stems, and the other half contained low-frequency stems. To each stem, four inflections of different lengths were attached (-a, -ari, -aren, and -arentzat, i.e., inflectional sequences). To test whether the process of word recognition was modulated by the knowledge of word structure in the language, half of the participants’ native language was Basque and the other half’s native language was Spanish. Children showed robust effects of frequency and length of inflection that diminished with age. In addition, the effect of length of inflection was modulated by the frequency of the stem and by the native language. Taken together, these results suggest that word recognition develops from a decoding strategy to a direct lexical access strategy and that this process is modulated by children’s knowledge of the inflectional structure of words from the beginning of their reading experience.     

Does “whole-word shape” play a role in visual word recognition?

To analyze the impact of outline shape on visual word recognition, the visual pattern of the stimuli can be distorted by size alternation. Contrary to the predictions of models that rely on outline shape (Allen, Wallace, & Weber, 1995), the effect of size alternationwas greater for low-frequency words than for high-frequency words in a lexical decision task (Experiment 1). In Experiment 2, the effect of case type (lowercase vs. UPPERCASE) occurred for low-frequency words, but not for high-frequency words. The effect of neighborhood size was remarkably similar in the two experiments. The results can be readily explained in the framework of a resonance model (Grossberg & Stone, 1986), in which a mismatch between the original sensory pattern and the abstract orthographic code slows down the formation of a stable percept.     

On the flexibility of letter position coding during lexical processing: the case of Thai

In Indo-European languages, letter position coding is particularly noisy in middle positions (e.g., judge and jugde look very similar), but not in the initial letter position (e.g., judge vs. ujdge). Here we focus on a language (Thai) which, potentially, may be more flexible with respect to letter position coding than Indo-European languages: (i) Thai is an alphabetic language which is written without spaces between words (i.e., there is a degree of ambiguity in relation to which word a given letter belongs to) and (ii) some of the vowels are misaligned (e.g., [see text] ε:bn/ is pronounced as /bε:n/), whereas others are not (e.g., [see text]/a:p/ is pronounced as /a:p/). We conducted a masked priming lexical decision experiment with 3-4 letter Thai words (with vs. without an initial misaligned vowel) in which the prime was: (i) identical to the target, (ii) a nonword generated by transposing the two initial letters of the target, or (iii) a replacement-letter control nonword. Results showed a significant masked transposed-letter priming effect in the initial letter positions, which was similar in size for words with and without an initial misaligned vowel. These findings reflect that: (i) letter position coding in Thai is very flexible and (ii) the nature of the obtained priming effects is orthographic rather than phonological.