Children's Immediate Understanding OF Vocabulary: Contexts and Dictionary Definitions

This study investigates children's ability to utilize context cues (forward or backward), dictionary definitions (original or revised), or combinations of the two to understand unfamiliar words. Significant word gains were found for all treatments and reading skill levels. Revised definitions produced significantly greater gains than forward context cues, backward context cues, and original definitions. Combined treatments produced significantly greater gains than backward context cues. Advanced readers demonstrated significantly greater gains than average or below-average readers. Implications for reading research and instruction are forwarded and the construct of Immediate Understanding is defined and explored.     

Reading skill and the identification of words in discourse context

Word identification latencies and word prediction accuracy were compared for groups of skilled and less skilled young readers in three experiments. In each experiment, discourse context reduced identification latencies for less skilled as well as skilled readers. This was true both when context was heard and when it was read. The general relationship between word predictability and latency was the same for skilled readers and for less skilled readers, but only less skilled readers’ identification latencies were affected by word length and word frequency when the word appeared in context. When subjects predicted the word before identifying it, correctly predicted words were identified more quickly than words not predicted correctly, and skilled readers were more accurate in prediction than were less skilled readers. Although reading-related differences in the use of discourse context may characterize other aspects of reading comprehension, the use of context in identifying words is not a major source of reading difficulty.     

First-order approximation to English,second-order approximation to English,and orthographic neighbor ratio norms for 925 nouns

First- and second-order approximations to English and orthographic neighbor ratio values are provided for Paivio, Yuille, and Madigan’s (1968) 925 nouns. First- and second-order approximations to English are information theory measures of the probability of generating a word on a letter-by-letter basis. The orthographic neighbor ratio is the frequency of a word divided by the sum of the frequencies of all words that can be generated by changing one of its letters. Thus, the orthographic neighbor ratio provides a measure of a sophisticated guessing model in which partial information about a word is obtained and a decision is made on the basis of the relative frequencies of the possible responses. Correlations with existing norms are reported.     

Guessing Strategies, Aging, and Bias Effects in Perceptual Identification

In the typical single-stimulus perceptual identification task, accuracy is improved by prior study of test words, a repetition priming benefit. There is also a cost, inasmuch as previously studied words are likely to be produced (incorrectly) as responses if the test word is orthographically similar but not identical to a studied word. In two-alternative forced-choice perceptual identification, a test word is flashed and followed by two alternatives, one of which is the correct response. When the two alternatives are orthographically similar, test words identical to previously studied items are identified more accurately than new words (a benefit) but tests words orthographically similar to studied words are identified less accurately than new words (a cost). Ratcliff and McKoon (in press) argue that these are bias effects that arise in the decision stage of word identification. We report five experiments that examined the alternative hypothesis that these bias effects arise from postperceptual guessing strategies. In single-stimulus perceptual identification, repetition priming benefits were equally great for young and older adults who claimed to use deliberate guessing strategies and those who did not (Experiment 1). In contrast, only groups of young and older people who claimed to deliberately guess studied words in a two-alternative forced-choice task (Experiments 2 and 5) showed reliable benefits and costs. Costs and benefits were abolished in the two-alternative forced-choice task when a very long study list was used, presumably because the increased retrieval burden made the use of deliberate guessing strategies less attractive (Experiment 3). Under conditions similar to those of Experiment 3, repetition priming was observed in single-stimulus perceptual identification (Experiment 4). These results are consistent with the view that costs and benefits in the forced-choice perceptual identification task arise from deliberate guessing strategies but that those in the single-stimulus task do not. The possibility that the observed relationship between strategy reports and priming effects reflects erroneous postexperimental assessments of strategies by participants is also considered.     

A role for backward transitional probabilities in word segmentation?

A number of studies have shown that people exploit transitional probabilities between successive syllables to segment a stream of artificial continuous speech into words. It is often assumed that what is actually exploited are the forward transitional probabilities (given XY, the probability that X will be followed by Y), even though the backward transitional probabilities (the probability that Y has been preceded by X) were equally informative about word structure in the languages involved in those studies. In two experiments, we showed that participants were able to learn the words from an artificial speech stream when the only available cues were the backward transitional probabilities. Learning is as good under those conditions as when the only available cues are the forward transitional probabilities. Implications for some current models of word segmentation, particularly the simple recurrent networks and PARSER models, are discussed.     

Backward recall and the word length effect

The word length effect, the finding that words that have fewer syllables are recalled better than otherwise comparable words that have more syllables, is one of the benchmark effects that must be accounted for in any model of serial recall, and simulation models of immediate memory rely heavily on the finding. However, previous research has shown that the effect disappears when participants are asked to recall the items in strict backward order. The present 2 experiments replicate and extend that finding by manipulating the participant's foreknowledge of recall direction (Experiment 1) and by giving the participant repeated practice with one direction by blocking recall direction (Experiment 2). In both experiments, a word length effect obtained with forward but not backward recall. The results are problematic for all models that currently have an a priori explanation for word length effects. The finding can be accounted for but is not predicted by Scale-Independent Memory, Perception, and Learning (SIMPLE), a model in which item and order information are differentially attended to in the 2 recall directions.     

Lexical ambiguity, semantic context, and visual word recognition.

Some alternative hypotheses about the recognition of ambiguous words are considered. According to the selective-access hypothesis, prior semantic context biases people to access one meaning of an ambiguous word rather than another in lexical memory during recognition. In contrast, the nonselectiveaccess hypothesis states that all meanings of the word are accessed regardless of the context. We tested certain versions of these hypotheses by having students decide whether selected strings of letters were English words. The stimuli included test sequnces of three words in which the second word had two distinct possible meanings, whereas the first and third words were related to these meanings in various ways. When the first and third words were related to the same meaning of the ambiguous second word (e.g., SAVE-BANK-MONEY), the reaction time to recognize the third word decreased. But when the first and third words were related to different meanings of the second word (e.g., RIVER-BANK-MONEY), the reaction time for the third word was not reliably different from a control sequence with unrelated words. These and other data favor the selective-access hypothesis. Selective access to lexical memory is discussed in relation to models of word recognition.     

The word-detection effect: Sophisticated guessing or perceptual enhancement?

Subjects discriminate letters in words better than letters in nonwords. The sophisticated guessing hypothesis attributes this word advantage to a guessing strategy. In words, the possible letters at each letter position are constrained by letters at other positions, whereas letters in nonwords are not restricted in this manner. A critical test of this hypothesis is that if subjects are givenexplicit knowledge of the letters in nonwords before the trial, the word advantage would disappear. We investigated the effect of preknowledge of the alternatives in the word-detection effect. In the word-detection effect, subjects decide which of two character strings contains letters and which contains pseudoletters. In four experiments, subjects were more accurate with words than with nonwords, and subjects were more accurate when they were told the word or nonword before the trial. However, even with foreknowledge of the alternatives, subjects were more accurate with words than with nonwords.     

Sentence context modulates visual word recognition and translation in bilinguals

The influence of sentence context constraint on subsequent processing of concrete and abstract cognates and noncognates was tested in three experiments. Target words were preceded by a predictive, high constraint sentence context, by a congruent, low constraint sentence context, or were presented in isolation. Dutch-English bilinguals performed lexical decision in their second language (L2), or translated target words in forward (from L1 to L2) or in backward (from L2 to L1) direction. After reading a high constraint sentence context, cognate and concreteness effects disappeared in lexical decision and strongly decreased in both translation tasks. In contrast, low constraint sentences did not influence cognate and concreteness effects. These results suggest that semantically rich sentences modulate cross-language interaction during word recognition and word translation.     

Exploring the cohort model of spoken word recognition

Predictions derived from the Cohort Model of spoken word recognition were tested in four experiments using an auditory lexical decision task. The first experiment produced results that were compatible with the model, in that the point at which a word could be uniquely identified appeared to influence reaction times. The second and third experiments demonstrated that the processing of a nonword phoneme string continues after the point at which there are no possible continuations that would make a word. The number of phonemes following the point of deviation from a word was shown to affect reaction times, as well as the similarity of the nonword to a word. The final experiment demonstrated a frequency effect when high and low frequency words were matched on their point of unique identity. These last three results are not consistent with the Cohort Model and so an alternative account is put forward. According to this account, the first few phonemes are used to activate all words beginning with those phonemes and then these candidates are checked back to the original stimulus. This model provides greater flexibility than the Cohort Model and allows for mispronounced and misperceived words to be correctly recognized.     

Is alphabet biasing in bialphabetical word perception automatic and prelexical?

Phonologically ambiguous Serbo-Croatian words are identified more slowly and erroneously than their phonologically unique counterparts. Five experiments addressed the reduction of these ambiguity effects when Roman (Cyrillic) targets are preceded by consonants unique to the Roman (Cyrillic) alphabet. Alphabet-specific nonword contexts were presented briefly with masking. With forward masking, performance was better when the phonologically ambiguous target words and their preceding nonword contexts were alphabetically congruent. Similarly, where backward masked contexts acted themselves as backward masks for the target stimuli, identification was highest when the context masks were in the same alphabet as the targets. Results were discussed in terms of automatic, prelexical processes within a network model of visual word recognition in Serbo-Croatian.     

Repetition blindness and homophone blindness in young and older adults

We tested age effects on repetition blindness (RB), defined as the reduced probability of reporting a target word following presentation of the same word in a rapidly presented list. We also tested age effects on homophone blindness (HB), in which the first word is a homophone of the target word rather than a repeated word. Thirty young and 28 older adults viewed rapidly presented lists of words containing repeated, homophone, or unrepeated word pairs and reported all of the words immediately after each list. Older adults exhibited a greater degree of RB and HB than young adults using a conditional scoring method that provides certainty that blindness has occurred. The existence of RB and HB for both age groups, and increased blindness for older compared to young adults, supports predictions of a binding theory that has successfully accounted for a wide range of phenomena in cognitive aging.     

The Role of Negative Information in Distributional Semantic Learning

Distributional models of semantics learn word meanings from contextual co‐occurrence patterns across a large sample of natural language. Early models, such as LSA and HAL (Landauer & Dumais, 1997; Lund & Burgess, 1996), counted co‐occurrence events; later models, such as BEAGLE (Jones & Mewhort, 2007), replaced counting co‐occurrences with vector accumulation. All of these models learned from positive information only: Words that occur together within a context become related to each other. A recent class of distributional models, referred to as neural embedding models, are based on a prediction process embedded in the functioning of a neural network: Such models predict words that should surround a target word in a given context (e.g., word2vec; Mikolov, Sutskever, Chen, Corrado, & Dean, 2013). An error signal derived from the prediction is used to update each word's representation via backpropagation. However, another key difference in predictive models is their use of negative information in addition to positive information to develop a semantic representation. The models use negative examples to predict words that should not surround a word in a given context. As before, an error signal derived from the prediction prompts an update of the word's representation, a procedure referred to as negative sampling. Standard uses of word2vec recommend a greater or equal ratio of negative to positive sampling. The use of negative information in developing a representation of semantic information is often thought to be intimately associated with word2vec's prediction process. We assess the role of negative information in developing a semantic representation and show that its power does not reflect the use of a prediction mechanism. Finally, we show how negative information can be efficiently integrated into classic count‐based semantic models using parameter‐free analytical transformations.     

Phonological priming in auditory word recognition

Cohort theory, developed by Marslen-Wilson and Welsh (1978), proposes that a "cohort" of all the words beginning with a particular sound sequence will be activated during the initial stage of the word recognition process. We used a priming technique to test specific predictions regarding cohort activation in three experiments. In each experiment, subjects identified target words embedded in noise at different signal-to-noise ratios. The target words were either presented in isolation or preceded by a prime item that shared phonological information with the target. In Experiment 1, primes and targets were English words that shared zero, one, two, three, or all phonemes from the beginning of the word. In Experiment 2, nonword primes preceded word targets and shared initial phonemes. In Experiment 3, word primes and word targets shared phonemes from the end of a word. Evidence of reliable phonological priming was observed in all three experiments. The results of the first two experiments support the assumption of activation of lexical candidates based on word-initial information, as proposed in cohort theory. However, the results of the third experiment, which showed increased probability of correctly identifying targets that shared phonemes from the end of words, did not support the predictions derived from the theory. The findings are discussed in terms of current models of auditory word recognition and recent approaches to spoken-language understanding.     

Inhibitory control during sentence reading in dyslexic children.

The present study focused on the nature of the reading disability of children with the guessing subtype of dyslexia (who read fast and inaccurately). The objective was to separate the excitatory account of their reading disturbance (i.e., in guessers the words' resting levels of activation are oversensitive to semantic context) from the inhibitory account (i.e., guessers tend to react prematurely to (false) candidate words that are activated in the lexicon). To disentangle the above accounts, guessers and normal readers were presented with a sentential priming task (SPT). In the SPT, subjects had to determine whether the final word of a sentence was semantically congruent or incongruent with the sentence, but had to inhibit their 'congruent' or 'incongruent' response in case of an occasionally presented pseudoword. To evoke guessing, each pseudoword closely resembled either a valid congruent or incongruent word. Guessing referred to prematurely accepting a pseudoword as a word that either appropriately or inappropriately completed the sentence. The extent to which subjects guessed at word meaning was evidenced by the false recognition rates (FRR) of the misspelled terminal words. Analyses on the FRRs of the pseudowords showed that guessers had significantly more difficulty in suppressing the 'go tendency' triggered by the pseudowords. It was concluded that the impulsive reading style of guessers should be ascribed to a less efficient suppression mechanism rather than to excessive reliance on contextual information. Specifically, the data were explained by assuming that the availability of the pseudoword's candidate meaning activated the hand to respond with, and that guessers found difficulty in suspending this response until they analyzed all letters in the stimulus and they could be sure of its spelling.     

Expectancy,integration, and interactional processes: Age differences in the nature of words affected by sentence context

Two experiments investigated sentence context effects on the naming times of sentence completion words by third-grade children and college students. Across both experiments, the largest age difference in contextual facilitation was obtained for highly predictable, best completion words. Pronounced age differences in facilitation effects were also present for semantically acceptable target words which were much less predictable in the sentence context than the best completion words. However, age differences in contextual facilitation were negligible for target words which were associatively related to the best completion word, but which were not also semantically acceptable in the sentence context. Thus, the semantic acceptability of the word in the sentence context had a much greater influence on children's as compared to adults' word identification times, both when the word was highly predictable, as well as when it was much less predictable in the sentence context.     

Modulating semantic feedback in visual word recognition

According to the interactive activation framework proposed by McClelland and Rumelhart (1981), activation spreads both forward and backward between some levels of representation during visual word recognition. An important boundary condition, however, is that the spread of activation from lower to higher levels can be prevented (e.g., explicit letter processing during prime processing eliminates the well-documented semantic priming effect). Can the spread of activation from higher to lower levels also be prevented? This question was addressed with a choice task procedure in which subjects read a prime word and then responded to a target, performing either lexical decision or letter search depending on the color of the target. A semantic context effect was observed in lexical decision, providing evidence of semantic-level activation. In contrast, there was no semantic context effect in the letter search task, despite evidence of lexical involvement: Words were searched faster than nonwords. Further evidence of lexical involvement in the letter search task appeared in Experiment 2 in the form of greater identity priming for words than for nonwords. The results of these experiments are consistent with the conclusion that feedback from the semantic level to the lexical level can be blocked. Hence, between-level activation blocks can be instantiated in both bottom-up and top-down directions.     

Speech identification and “knowing that you know”

Twenty-five Ss heard a random list and a context (food-elated) list of 50 words masked in white noise for a total of three trials each. The Ss were required to write the word and indicate their certainty that it was correct. Confidence rating accuracy (Type 2 d’) was greater for context than for random lists (p < .001). Probability correct also improved with context (p < .001). Unlike the context factor, repetitions led to greater probability correct (p < .001) but did not lead to changes in Type 2 d’. The results were interpreted as support for a feedback model of context and confidence rating accuracy.     

Context and the allocation of resources in word recognition

Three experiments are reported that investigate the effects of context on the use of limited processing resources in word recognition. On each trial in all of the experiments, the subjects were presented with an incomplete sentence followed by a target display containing a word and two digits. In all cases, accuracy at reporting the word was affected by context, as expected. The effect of context on processing resources was examined by considering the accuracy of reports of the digits in cases in which the word did or did not fit the context. Accuracy of digit report was greater for digits surrounding words in related context, but only when the subjects were required to report the word before reporting the digits. There was no effect of word context on the digit report when subjects had to report the digits first. There was likewise no effect on accuracy of digit report when subjects were required to report only the word or only the digits, even when the cue was presented 250 msec after the target display was replaced by a patterned mask. The results suggest that the effect of context on the resources consumed in word recognition is restricted to aspects of processing that can be delayed until the subject is required to select an overt response, and a simple interpretation of the results may be given in terms of a slight modification of Morton's model of the interaction of stimulus information and context.     

不熟练汉英双语儿童翻译加工的特点

本研究使用单词翻译、图片命名和单词命名任务探查了不熟练的小学三、五和初一年级汉英双语儿童前向翻译和后向翻译的内在过程,结果发现,(1)各组被试命名图片和单词的语言效应显著,用第二语言命名图片和单词的反应时显著长于用第一语言命名图片和单词的反应时;(2)各组被试在前向翻译的反应时显著长于后向翻译,随着第二语言熟练程度的提高,反应时的差异逐渐减小。对结果的分析表明,不熟练的汉英双语儿童在两个翻译方向的内在过程相同,都是概念中介的,但两个翻译方向的加工速度差异显著。