Missing-letter Effect Research Articles

Eye movements as direct tests of the GO model for the missing-letter effect

When asked to detect target letters while reading a text, participants miss more letters in frequently occurring function words than in less frequent content words. To account for this pattern of results, known as the missing-letter effect, Greenberg, Healy, Koriat, and Kreiner proposed the guidance-organization (GO) model, which integrates the two leading models of the missing-letter effect while incorporating innovative assumptions based on the literature on eye movements during reading. The GO model was evaluated by monitoring the eye movements of participants while they searched for a target letter in a continuous text display. Results revealed the usual missing-letter effect, and many empirical benchmark effects in eye movement literature were observed. However, contrary to the predictions of the GO model, response latencies were longer for function words than for content words. Alternative models are discussed that can accommodate both error and response latency data for the missing-letter effect.

Short Article: The interaction of word frequency and word class: A test of the GO model's account of the missing-letter effect

When asked to detect target letters while reading a text, participants miss more letters in frequent function words than in less frequent content words. In this phenomenon, known as the missing-letter effect, two factors covary: word frequency and word class. According to the GO model, there should be an interaction between word class and word frequency with more omissions for function than for content words only among high-frequency words. This pattern would be due to the fact that function words could only assume a structure-supporting role if they are identified rapidly, which is only possible for high-frequency words. These predictions were tested by assessing omission rate for frequent and rare function and content words. Results lend support to the GO model with more omissions for frequent than for rare words, and more omissions for the function than for the content word among high-frequency words, but not among low-frequency words. These results were observed both in English (Experiment 1) and in French (Experiment 2).

German Capitalization of Nouns and the Detection of Letters in Continuous Text.

The missing-letter effect refers to the phenomenon that letters are more difficult to detect in common function words (such as the) than in content words. Assuming that the missing-letter effect is diagnostic of the extraction of text structure, we exploited a special feature of German--the convention to capitalize the initial letter of nouns. Given the great flexibility of word order in German, it was proposed that this convention might help readers specify the structure of the sentence. Therefore orthographic variations that violate the capitalization rules should disrupt structure extraction and should result in a reduced missing-letter effect. The results indicated that: 1) capitalization of function words eliminated the missing-letter effect, but not at the beginning of a sentence; 2) A missing-letter effect occurred when the capitalization of the first letter was correct, but was followed by typecase alternation, and also when the size of the initial letters was relatively large for function words, but relatively small for content words. The results were discussed with respect to the possible contributions of visual familiarity, structural role, and processing time to the missing-letter effect, taking into account that a capitalized initial letter conveys significant information about the word class for German readers. Thus, the present results indicate that readers take advantage not only of function words but of any other information (here the capitalization of nouns) that helps to extract the structure of a sentence.

Age changes in the missing-letter effect revisited

When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequent function words than in less frequent content words. Reflecting developmental changes in component language and literacy skills, the size of this effect increases with age. With adults, the missing-letter effect is due to both word function and word frequency. With children, it is unclear whether the growing size of the missing-letter effect across development is due to a larger effect of word function, word frequency, or both because previous studies with children seeking to isolate the influence of word frequency and word function suffer from important methodological limitations. With these methodological limitations eliminated (Experiments 1 and 2), performance in a letter detection task was assessed for children in Grades 1, 2, 3, 4, and 7 as well as for undergraduate students. The results revealed that the influence of word function increases with age, whereas the effect of frequency is fairly stable across ages. Furthermore, normative predictability data collected in Experiment 3 revealed that third graders and undergraduate students were equally good at predicting function slots in a sentence.

The GO model: a reconsideration of the role of structural units in guiding and organizing text on line.

Healy (1994) and Koriat and Greenberg (1994) offered different theoretical accounts of the missing-letter effect (MLE) in the letter-detection task, whereby a disproportionate number of letter-detection errors occur in frequent function words. Healy emphasized identification processes, whereas Koriat and Greenberg viewed the structural role of the embedding word to be crucial. Recent research suggests that neither position alone can account for the complete set of observations pertaining to the MLE. The present paper offers a theoretical integration of these competing explanations of letter detection in terms of a GO (guidance-organization) model of reading. This model specifies how structural processing of connected text helps guide eye movements to semantically informative parts of the text, enabling readers to achieve on-line fluency.

One missing-letter effect: two methods of assessment.

When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequent function words than in less frequent content words. This effect is usually observed with a paper and pencil procedure. It has been shown that a similar pattern is observed using a rapid serial visual presentation procedure in which words appear one at a time on a computer screen. It has been questioned, however, whether the two methods tap the same cognitive processes. Item-based correlations between the paper and pencil and the rapid serial visual presentation procedure were high and not significantly different from reliability estimates of either procedure. It is concluded that both procedures highlight the same cognitive processes that are responsible for the missing-letter effect.

Direct assessments of the processing time hypothesis for the missing-letter effect.

When participants search for a target letter while reading, they make more omissions if the target letter is embedded in frequently used words or in the most frequent meaning of a polysemic word. According to the processing time hypothesis, this occurs because familiar words and meanings are identified faster, leaving less time for letter identification. Contrary to the predictions of the processing time hypothesis, with a rapid serial visual presentation procedure, participants were slower at detecting target letters for more frequent words or the most frequent meaning of a word (Experiments 1 and 2) or at detecting the word itself instead of a target letter (Experiment 3). In Experiments 4 and 5, participants self-initiated the presentation of each word, and the same pattern of results was observed as in Experiments 1 and 3. Positive correlations were also found between omission rate and response latencies.

Influence of parafoveal processing on the missing-letter effect.

Influence of parafoveal processing on the missing-letter effect.

Age Changes in the Missing-Letter Effect Reflect the Reader's Growing Ability to Extract the Structure from Text

Readers searching for a target letter in text are more likely to miss it in frequent function words than in less frequent content words, and the magnitude of this effect increases with age. While this increase has been taken to indicate that proficient readers process familiar words in terms of larger orthographic units, we propose that it reflects the reader's growing ability to extract the structure of text, resulting in a reduced emphasis on function than on content words. Indeed, comparing 2nd graders (7 to 7 1/2 years) and college students (Experiment 1) this increase was found even when function and content words were equated for frequency. Scrambling words within a sentence (Experiment 2) improved letter detection in function compared to content words among 7th graders (12 to 13 years) and college students, but not among 3rd graders (8 to 9 years). Although letter detection was also affected by word frequency, the age differences noted above are possibly due not to the increasing familiarity of words, but rather to the growing sensitivity to their structural role in text.

The influence of word function in the missing-letter effect: Further evidence from French

When asked to detect target letters while reading continuous text, subjects miss more letters in highly common function words than in less common content words. This is known as the missing-letter effect. According to the structural account, the higher omission rates for frequent function words are attributable to their role in supporting the extraction of phrase structure, after which they become lost in the transition from structure to meaning. This implies that word function in and of itself should affect letter detection accuracy. This issue was examined in four experiments while controlling for a number of confounded factors associated with another influential model: the unitization account. The first experiment extended the missing-letter effect to the French language. The second showed that letter detection is influenced by slight variations in the function assumed by the same word, such as when it is used as a definite article as opposed to a pronoun. This effect was observed even when the frequency of the orthographic pattern and the syllable stress patterns were controlled. In the last two experiments, a control was added for another factor: frequency of word meaning. The results indicate that word function contributes to the missing-letter effect over and above what is contributed by frequency of word meaning.

The missing-letter effect in Hebrew: Word frequency or word function?

In this article, the authors attribute the missing-letter effect in Hebrew to the linguistic function of the words

The missing-letter effect in Hebrew: Word frequency or word function?

The missing-letter effect in Hebrew: Word frequency or word function?

The missing-letter effect for common function words depends on their linguistic function in the phrase.

The missing-letter effect for common function words depends on their linguistic function in the phrase.

The missing-letter effect for common function words depends on their linguistic function in the phrase.

It has been proposed that function words such as for and on conceal their letters because their higher familiarity allows fast access to their unitized representations. However, in this study we show that letter detection in function words varies with their linguistic role in text. When such words were embedded in a phrase where they were forced into a content role by the surrounding context (e.g., for or against or on switch), letter detection improved markedly and did not differ from that of matched content words. The result was replicated when the context preceding the function word and the overall sentential meaning were equated for both function and content usages