Some boundary conditions for a word superiority effect

A word superiority effect was obtained using a fixed stimulus set, positional certainty of the critical letter, mixed trial type, and instructions to fixate the critical letter. Control experiments established that this effect was not due to lateral masking. Further experiments extended the finding of a fixed-set word superiority effect to other stimulus sets, and to lowercase and mixed-case stimuli. The mixed-case word superiority effect is inconsistent with supraletter feature models of word recognition and, instead, lends support to hierarchical codes models. It was demonstrated that an unusually wide spacing of letters can disrupt the formation of word-level codes, and that wide visual angles are not necessarily disruptive as long as normal spacing is maintained.     

The word superiority effect: A comparison between restricted and unrestricted alternative set

Three experiments were conducted to investigate the word superiority effect (WSE) (Reicher, 1969). The first two experiments used mixed presentations of words and nonwords, and positional uncertainty of the critical letter. Experiment 1 used an unrestricted set of alternatives, while Experiment 2 used only two alternatives (R and L). Experiment 3 compared letter detection in nonwords with a restricted and unrestricted alternative set. WSE was found for both Experiments 1 and 2, at about the same level. Experiment 3 showed superior performance when alternatives were known in advance. It was concluded that context has an effect on letter recognition even with prior knowledge of alternatives if the critical position is not known in advance. Some incompatibilities between the present results and those of other investigators in the field are discussed.     

An analysis of the word-superiority effect

It is easier to decide which of two letters was presented tachistoscopically if the critical letter was in a word rather than in a scrambled word. We showed that this word-superiority effect holds just as strongly for pronounceable nonwords as for words, even when the critical letters are constant over all trials. This finding rules out word meaning and familiarity as variables accounting for the effect. In addition, it was found that the superiority of pronounceable stimuli holds for two-letter stimuli as well as four, and it is therefore concluded that the effect is not due to a memory limitation. An explanation of the effect in terms of the use of additional acoustic information is ruled out by showing that the effect was not diminished when the two possible words sounded exactly alike. An experiment using correctly and incorrectly spelled chemical formulas suggested that spelling regularities, regardless of pronounceability per se, account for the superiority effect. Finally, when decisions about two critical letters must be made on each trial, the correlation between being correct on one and on the other is higher for pronounceable stimuli under some conditions.     

The word superiority effect in a case ofHiragana letter strings

This paper is concerned with the effect of syllabification in the superior perceptibility of tachistoscopically presented JapaneseHiragana letter strings. TheHiragana letter is a phonetic symbol having an invariant one-syllable pronunciation. Controlling retention and guessing factors, an experiment replicated the original Reicher (1969) findings of a word superiority effect. Thus, the results suggest that letter unitization which depends upon syllable-like structures (the vocalic center groups; Spoehr & Smith, 1973) is not a prerequisite, but that orthographic regularity and meaningfulness may be important determinants of the word superiority effect.     

The effects of display and report order asymmetries on lateralized word recognition

Word recognition typically is better or faster in the right visual field than in the left visual field, an effect that often interacts with the handedness of subjects or the phonetic characteristics of the language employed. While these findings suggest a hemispheric locus, it is possible that the field difference is confounded with display or report order asymmetries. Here two experiments manipulate word orientation (horizontal vs. vertical), letter symmetry, and report order variables, and they demonstrate a generalized right field superiority that fails to interact with other factors. Since the superiority appears even when all apparent artifactual asymmetries are eliminated, the findings support a hemispheric interpretation.     

The word superiority effect: Dependence on short-term memory factors

Two experiments were conducted to test whether the word superiority effect, that letters in words are perceived more accurately than letters in nonwords, could be attributed to short-term memory (STM) factors. One hypothesis attributed the word superiority effect to superior maintenance of words in STM. Another hypothesis was that letters in STM have considerable positional uncertainty which is overcome by the orthographic characteristics of the words. Both experiments utilized a simultaneous same-different task, where subjects compared two four-letter strings, one on top of the other, which were presented tachistoscopically. In Experiment I, the two presented strings were either both words or both nonwords and a word superiority effect was obtained. This result was interpreted as disconfirming the STM maintenance hypothesis. In Experiment II, letters were removed from one of the two letter strings, making the serial position of the comparison unambiguous. The word superiority effect disappeared. This result was interpreted as supporting the positional uncertainty hypothesis.     

Classification and identification thresholds for three types of verbal materials

The first two experiments found thresholds for classification into one of three categories of English words, Turkish words, and letter alternations to be significantly lower than thresholds for the identification of the specific items; parallel results were found with the two methods of measurement employed. Both thresholds were lowest for English words, and classification thresholds were lower for Turkish words than for letter alternations, but the identification thresholds of these two kinds of materials showed a reversal. The third experiment found classification thresholds for the same three types of materials to be higher than either of two three-choice identification thresholds, one a choice among three sametype items and the other, a choice among one English word, one Turkish word, and one letter alternation.     

Identification of letters in the predesignated target paradigm: a word superiority effect for the common word the

The size of the perceptual unit used in reading was addressed using the predesignated target paradigm. Sixteen subjects viewed the following stimuli in random order: the words tee, the, tie, and toe; the nonwords eet, eht, eit, and eot; and the letters e, h, i, and o. Subjects fixated on the location of the center letter and identified the letter as e, h, i, or o, alternatives which were known to them at the onset. A word superiority effect was obtained for the common word the but not for the less common words tee, tie, and toe. The word superiority effect was attributable to bias rather than discriminability: Subjects exhibited a bias to perceive the words in this experiment as the (i.e., there was a bias to perceive h in the t e stimulus presentations). These results suggest that the common word the is processed in reading units that are larger than the letter, and that the system is biased to perceive common rather than uncommon words in data-limited conditions.     

Classification and identification thresholds for three types of verbal materials

The first two experiments found thresholds for classification into one of three categories of Erlglish words, Turkish words, and letter alternations to be significantly lower than thresholds for the identification of the specific items; parallel results were found with the two methods of measurement employed. Both thresholds were lowest for English words, and classification thresholds were lower for Turkish words than for letter alternations, but the identification thresholds of these two kinds of materials showed a reversal. The third experiment found classification thresholds for the same three types of materials to be higher than either of two three-choice identification thresholds, one a choice among three same-type items and the other, a choice among one English word, one Turkish word, and one letter alternation.     

Investigating the boundaries of reading units: letter detection in misspelled words

In two experiments, subjects searching for the letter t in passages that contained some misspellings made many more errors on the word the than on other correctly spelled words. Accuracy increased dramatically when the word the and the other words containing t were misspelled, even when the misspelled word was the same shape as the original. These findings define a word-inferiority effect, which stands in contrast to the superior perception of letters in words over nonwords commonly found in tachistoscopic studies. In a third experiment, subjects searched for the letter n in passages typed normally or typed with all interword spaces replaced by the symbol +. Detection errors on the word and were greatly reduced when the interword spaces were replaced by +s, but errors on other words, including those ending in the suffix morpheme -ing, were not affected by this manipulation. These results suggest that frequent function words are processed in terms of reading units that are larger than the letter and include the interword spaces.     

Scanning,holistic encoding,and the word-superiority effect

The role of holistic encoding induced by scanning in the superior identifiability target letters in orthographic strings (words) enjoy over those in strings of unrelated letters was examined in two experiments. Both the set of potential targets and the critical position in the letter arrays were predesignated. One group in each experiment was induced to scan each array from left to right in a dot-counting task. A dot could precede the array to its left and/or appear with the array to its right. Only this group displayed the word superiority. For the second group in the first experiment, any dot(s) present always appeared with the array. The second group in the second experiment was shown no dots but, rather, performed the letter-identification task only. The absence of a word-superiority effect in other studies is related to holistic encoding stemruing from scanning requirements, and the implications for positional uncertainty explanations of the phenomenon are discussed.     

Do small visual angles produce a word superiority effect or differential lateral masking?

Purcell, Stanovich, and Spector 119781 report that recognition of the center letter of the words APE, ARE, ACE, and AGE is superior to recognition of the same targets in the nonwords formed by the context letters V_H. Since a small set of predesignated targets was used and there was complete certainty about the location of the target letter, these results pose serious problems for three otherwise viable accounts for why word superiority effects (WSEs) are obtained in a variety of other paradigms. This series of experiments explores the possibility that the word advantages reported by Purcell et al. have nothing to do with the lexical properties of the A_E display or the general phenomenon of word superiority, but they result from a fortuitous case of differential lateral masking. This reinterpretation is supported by five experiments. Experiments 1 and 2 show that the A_E word advantages are anomalous in that the magnitude of the WSE obtained with these particular words is not contingent upon the presence of a patterned mask. Experiment 3 provides direct evidence for differential lateral masking by showing that digit recognition is poorer in the V_H than in the A_E frame. Experiments 4 and 5 show that the WSE obtained under these conditions does not generalize to a new set of words and nonwords that produce the same amount of lateral masking. It was concluded that a genuine WSE does not occur under the conditions tested by Purcell et al., and that, therefore, the WSE has not been shown to depend on visual angle.     

Temporal separation of two part-letter arrays and size changes in a nonmasking work-superiority effect

In two experiments subjects were asked to report the identity of a position-cued critical letter in an array of four letters. Four types of arrays were used: (i) unpronounceable nonwords; (ii) pronounceable nonwords ('pseudowords'); (iii) words in which the critical letter was minimally constrained by the context letters; and (iv) words in which the critical letter was maximally constrained by the context letters. All four-letter stimuli were presented in two parts. A leading array in which the information from two quadrants of a vertical by horizontal division of each letter was presented, and, after intervals of 0, 20, 40, 80, 100, 120, 160, 320, and 480 ms and infinity (ie, no trailing array), a trailing array of the complementary letter parts. In experiment 1 a single group of eight subjects responded to the one hundred and sixty combinations of the four types of letter strings, the four serial positions, and the ten stimulus onset asynchrony values. In experiment 2 the stimulus onset asynchrony values were varied among subjects, with twelve subjects responding at each value. The results from these two studies were generally similar. Performance in the word conditions was consistently superior to performance in the nonword conditions, and the magnitude of this difference (ie, the word-superiority effect) increased with increasing stimulus onset asynchrony up to 120 ms, and then gradually declined. The fact that the magnitude of the word-superiority effect initially increased with the separation of leading and trailing arrays was interpreted as support for Johnston's suggestion that letters in words are represented during visual encoding both in the form of individual letter percepts and in a decay-resistant word percept, as opposed to letters in nonwords, which are represented only as decay-susceptible letter percepts. The experimental findings are discussed in relation to the 'interactive activation' model of word perception.     

Word-to-letter inhibition: Word-inferiority and other interference effects

Four experiments were run to determine whether the interactive activation model would more accurately reflect the effect of context in letter perception by including word-to-letter inhibition resulting from word-to-word inhibition produced when multiple word units become active. The first three experiments found less accurate target letter discrimination in word than in nonword strings when a string was altered halfway through the exposure through adding or dropping a nontarget letter. The alteration changed a word to a different word or a nonword to a different nonword. Unaltered strings produced the typical word-superiority effect. The last experiment found an inverse relationship between target discrimination performance and the number of word substrings contained in each of a set of word quadrigrams that were individually exposed.     

Directional letter-by-letter analysis and the word-superiority effect

Manipulations were introduced in three experiments to produce letter-by-letter analysis of orthographic (CVC) and nonorthographic (CCV or VCC) trigrams. Letters in the trigrams were presented in a different form (normal orientation and order, normal orientation but reversed order, reversed orientation but normal order, or reversed orientation and order) to each of four groups in the first experiment, and in each of the two normal orientation forms to different groups in the second experiment. Subjects both detected the presence or absence of a target letter and classified each trigram as a word or nonword. Additional changes were introduced in the third experiment to ensure that letters were being analyzed in the desired order. Performance was consistently better on orthographic trigrams, but only if the letters were oriented normally. This word-superiority effect (WSE) was related to feature testing that may be carried out letter by letter, with more efficient testing on words. Failiar orientation of letter features seems to be necessary; otherwise, testing becomes so difficult that there is no WSE. However, testing apparently is not finished on a given letter before it is begun on the next.     

汉字认知过程中整字对部件的影响

英文研究中,"字优效应"是单词促进字母加工的一个重要依据。但中文研究中还存在一些争议。本研究通过两个实验考查了汉字的部件认知中,汉字整体对局部(部件)的影响。实验刺激材料分为三种,即左右结构或上下结构的真字、假字与部件字。目标部件为既能够放置于三种字符的左侧,又能放置于右侧(上部或下部)的汉字部件。实验一采用Reicher-Wheeler实验任务,先呈现刺激材料350ms,掩蔽后再呈现需要判断的目标部件,被试对目标部件进行按键反应。实验二中采用部件判断实验任务,先呈现需要判断的目标部件,再呈现刺激材料,被试对刺激材料中是否包含目标部件进行按键反应。记录反应时与正确率。27位健康女性大学生参与本实验。结果显示:(1)不论是Reicher-Wheeler实验任务还是部件判断实验任务,均显示部件字的部件认知判断速度最快。真字与假字相比,无"字优效应"。真字与部件字相比,存在着"字劣效应"。这些结果表明,汉字整字对汉字部件认知加工起到抑制作用;(2)两个实验任务均表现出汉字结构方式效应,即对左右结构的汉字的部件认知比上下结构的汉字更快;(3)部件的空间位置对部件识别存在影响。实验一中对下部件分辨最困难,分辨时间最长;实验二中发现对左部件的反应最快。字符结构方式效应与部件空间位置效应既存在于真字中,也存在于假字中。     

Is the optimal viewing position in reading influenced by familiarity of the letter string?

An optimal viewing position (OVP) for word recognition has been proposed by several authors. The location of this position would be located at the center of the word or just left of it. Several hypotheses ranging from perceptual to hemispheric factors have been proposed to explain this phenomenon. In the experiment presented here, the effect of the nature of the stimulus was tested: word, pseudo-word, or nonword on the existence and location of this position. Little research has investigated this issue. Five-letter words, pseudo-words, and non-words were presented, with the subject fixating initially on one of the five possible letter positions. The number of letters correctly identified and reading performance were recorded for each stimulus. Results show that an initial fixation on the third letter entails better letter identification for all kinds of stimuli. However, in terms of reading, only word reading benefit from a fixation on the third letter. These results are discussed in relation to the different hypotheses of OVP in reading. These are (1) hemispheric specialization, (2) reading habits, and (3) lexical constraints.     

Global,component, and serial processing of printed words in beginning reading

Nonreaders (end of kindergarten) and beginning readers (end of first grade) were compared. Both nonreaders and beginning readers imposed integral perceptual structures on shape/terminal letter information and configural perceptual structures on medial letter information: visual attention varied as a function of the unit of visual information but not as a function of learning to read. Nonreaders remembered a word more accurately than a letter in a word, showing visual origins of the word superiority effect. Beginning readers remembered a word faster than a letter in a word, which they remembered faster than a letter sequence in a word, suggesting early origins of the word priority effect. Only gains in memory for a letter sequence correlated with gains in word decoding. Throughout first grade, sentence verification was faster, not more accurate, when sentences were presented normally compared to one word at a time; repeated exposure of a word in parafoveal and foveal vision facilitates speed but not accuracy of comprehension. Results are discussed in reference to a model of global, component, and serial procedures.     

Left and right visual field superiority for letter classification

Two letter classification experiments examine the hypothesis that lateral asymmetries in perceptual processing are sensitive to subtle changes in task demands. The first experiment reports a right visual field superiority for an easy letter classification, but a left field superiority for a difficult classification using the same population of stimuli. Experiment II demonstrates that the right field superiority can be reversed if the easy classification trials are embedded among more difficult trials. The implications of these results for theories of hemispheric localization are discussed.     

Models of word recognition

Major hypotheses about the processes involved in word recognition are reviewed and then assessed through four experiments. The purpose of the first experiment was to examine some basic aspects of the processing of words, pseudowords, and nonwords, and beyond that, to discover basic differences in their processing that might underlie the word advantage. The second experiment was designed to assess the contribution of whole-word and letter cluster cues to the word advantage. Finally, Experiments III and IV were focused on the question of whether the word advantage can be wholly explained in terms of response bias or sophisticated guessing. Taken together, the results of these experiments were most compatible with criterion bias models. A version of the criterion bias model is suggested wherein the word advantage is attributed to interfacilitation among single letter and lexical units in memory.