Phonemic deficits in developmental dyslexia

Summary The present study explored a possible relationship between reading difficulties and speech difficulties. Dyslexic and normal readers, matched for Reading Age, were compared first on a reading task and secondly on a speaking task.In the first experiment, the two groups were asked to read nonsense words aloud. Both groups were able to read one-syllable nonwords equally well but the dyslexics had more difficulty than the normal readers when asked to read two-syllable nonwords. Moreover, they found two-syllable nonwords containing consonant clusters particularly difficult. The probability of their making an error increased with the number of consonant clusters.In the second experiment, the subjects were required to repeat real words and nonsense words of two, three, or four syllables. Both groups found nonsense words more difficult to repeat than real words. However, the relative difficulty of nonsense words over real words was greater for the dyslexic group. Their difficulty was especially marked when they had to repeat four-syllable nonsense words.Thus, in both experiments the dyslexic readers were more affected by the phonological complexity of the stimuli than the normal readers were. Hence, it was suggested that the dyslexic readers tested were subject to a general phonemic deficit which affected their ability to process both written and spoken words.     

聋人双字词音位识别的实验研究

聋人能利用视觉音素意识解码词汇语音。与健听人音位位置效应一致,聋人对汉字声母更敏感,但双字词中是否也有类似的声母优势还不清楚。采用音位识别任务探讨聋人双字词识别的声母优势及其原因,研究一利用编码方式考察指拼的作用,发现了声母识别优势,表明聋人能利用字母和指拼两种方式解码双字词语音且编码方式不影响声母优势;研究二进一步利用汉字位置探讨音位序列加工对声母识别优势的作用,结果发现了声母优势、首字优势及首字声母优势,表明聋人识别双字词音位在汉字水平、汉字音节内水平都遵循从左至右的序列加工,与健听人一致,同时还受指拼声母的特殊影响。整个研究表明,聋人识别汉字语音建立在视觉音素意识基础上,双字词的声母识别优势受指拼声母强化、双字词汉字位置效应、音节内音位位置效应的共同作用。     

The effect of Kana literacy acquisition on the speech segmentation unit used by Japanese young children

Three experiments were undertaken to investigate whether young children's segmentation units would change as they learned to read kana letters, which represent morae (subsyllabic rhythmic units). The first 2 experiments used a vocal-motor segmentation task to examine whether 4- to 6-year-olds preferred to segment spoken words containing the special syllables CVN, CVQ, or CV: into syllables or into morae. The third experiment used a target monitoring task for CVN to examine whether children's detection of the target syllable in a series of words would vary depending on the moraic constitution of the target and the moraic-syllabic status of the word initial in which the target was embedded. Results indicated that the children's conscious segmentation of words, except for those having a geminate stop consonant (CVQ), developed from being a mixture of syllable- and mora-based to being predominantly mora-based as they learned to read kana letters. The tendency toward mora-based segmentation was also found in the target monitoring task, which required segmentation at a less conscious level.     

Chronometric analysis of speech perception

The relationship between the phonological properties of speech sounds and the corresponding semantic entries was studied in two experiments using response time measures. Monosyllabic words and nonsense words were used in both experiments. In Experiment I. Ss were each presented with individual items and were required, in three different conditions, to respond positively if (1) the item contained a particular final consonant, (2) the item was a real word, (3) the item contained either a particular consonant or was a real word. Latencies indicated that separate retrieval of phonological and lexical information took about the same time. but that their combined retrieval was longer, indicating a serial or overlapping process. In Experiment II, Ss were presented with pairs of items, and they responded positively if (1) the two items were physically identical, (2) the two items were lexically identical (both real words or both nonsense words). Response latencies were longer for lexical than for physical matches. Lexical matches were’ significantly slower than physical matches even on the same pair of items. The results imply differential accessibility to separate loci of phonological and semantic features.     

The phonological similarity effect in serial recognition

An experiment is reported examining the effect of consistent phonemic similarity among list items on memory retention in a task that is independent of overt speech production, the serial recognition task. Lists of consonant-vowel-consonant (CVC) words and nonwords were constructed such that although phoneme overlap was manipulated (i.e., shared vowel and final consonant [_VC], initial consonant and vowel [CV_], or the two consonants [C_C]), similarity remained constant. The results show that the influence of sub-syllabic mechanisms on STM performance is independent of speech production processes, and similarity in the pattern of results suggests that the same mechanisms subserve the recall of words and nonwords in STM. It is argued that the results are more consistent with psycholinguistic models than nonlinguistic models of STM, and implications for current STM models are discussed.     

The phonological similarity effect in serial recognition

An experiment is reported examining the effect of consistent phonemic similarity among list items on memory retention in a task that is independent of overt speech production, the serial recognition task. Lists of consonant-vowel-consonant (CVC) words and nonwords were constructed such that although phoneme overlap was manipulated (i.e., shared vowel and final consonant [_VC], initial consonant and vowel [CV_], or the two consonants [C_C]), similarity remained constant. The results show that the influence of sub-syllabic mechanisms on STM performance is independent of speech production processes, and similarity in the pattern of results suggests that the same mechanisms subserve the recall of words and nonwords in STM. It is argued that the results are more consistent with psycholinguistic models than nonlinguistic models of STM, and implications for current STM models are discussed.     

Cues to speech segmentation: Evidence from juncture misperceptions and word spotting

The question of whether Dutch listeners rely on the rhythmic characteristics of their native language to segment speech was investigated in three experiments. In Experiment 1, listeners were induced to make missegmentations of continuous speech. The results showed that word boundaries were inserted before strong syllables and deleted before weak syllables. In Experiment 2, listeners were required to spot real CVC or CVCC words (C = consonant, V = vowel) embedded in bisyllabic nonsense strings. For CVCC words, fewer errors were made when the second syllable of the nonsense string was weak rather than strong, whereas for CVC words the effect was reversed. Experiment 3 ruled out an acoustic explanation for this effect. It is argued that these results are in line with an account in which both metrical segmentation and lexical competition play a role.     

Phonemic identification in a phoneme monitoring experiment: The variable role of uncertainty about vowel contexts

Subjects monitored for the syllable-initial phonemes /b/ and /s/, as well as for the syllables containing those phonemes, in lists of nonsense syllables. Time to detect /b/ was a function of the amount of uncertainty as to the identity of the vowel following the target consonant; when uncertainty was low, no difference existed between phoneme and syllable monitoring latencies, but when uncertainty was high, syllables were detected faster than phonemes. Time to detect /s/ was independent of uncertainty concerning the accompanying vowel and was always slower than syllable detection. The role of knowledge of contexts in a phoneme-monitoring task as well as the relative availability of phonemic information to the listener in this task are discussed.     

Phoneme monitoring and lexical processing: Evidence for associative context effects

In this paper, we propose a new version of the phoneme monitoring task that is well-suited for the study of lexical processing. The generalized phoneme monitoring (GPM) task, in which subjects detect target phonemes appearing anywhere in the test words, was shown to be sensitive to associative context effects. In Experiment 1, using the standard phoneme monitoring procedure in which subjects detect only word-initial targets, no effect of associative context was obtained. In contrast, clear context effects were observed in Experiment 2, which used the GPM task. Subjects responded faster to word-initial and word-medial targets when the target-bearing words were preceded by an associatively related word than when preceded by an unrelated one. The differential effect of context in the two versions of the phoneme monitoring task was interpreted with reference to task demands and their role in directing selective attention. Experiment 3 showed that the size of the context effect was unaffected by the proportion of related words in the experiment, suggesting that the observed effects were not due to subject strategies.     

Forgetting and redintegration of consonants and vowels in pseudoword lists

Immediate recall of phonemes was studied in a pseudoword span task. Finnish participants recalled lists of increasing length, consisting of C(consonant)V(vowel)CVCV pseudowords. The lists were made up from pools of 12 pseudowords. There were three types of lists. In the non‐redundant lists the items were unpredictable combinations of consonants and vowels. In consonant‐redundant lists, all items had the consonant frame /t/_/s/_/l/. In vowel‐redundant lists, all items had the vowel frame _/u/_/e/_/o/. Unlike redundant last syllables in a previous experiment, neither consonant nor vowel redundancy helped list recall. Instead, a harmful phonological similarity effect was apparent in the vowel‐redundant case but not the consonant‐redundant case. A phoneme‐level analysis of recall showed that consonants were recalled better in consonant‐redundant lists and vowels were recalled better in vowel‐redundant lists compared to non‐redundant lists. Vowels appeared to be more important for discrimination between items, with redundancy resulting in confusions. The consequences of phoneme‐level forgetting and redintegration for item‐ and list‐level recall are discussed.     

THE ACQUISITION OF GRAPHEME‐PHONEME CORRESPONDENCES IN A WORD LEARNING TASK

Abstract

The relationship between reading ability with receptive vocabulary level and the ability to induce grapheme‐phoneme relationships was investigated using grade one students. The ability to induce relationships was assessed by a word learning task in which the stimuli were six consonant‐vowel‐consonant trigrams composed of seven letter‐like forms with a 1:1 grapheme‐phoneme correspondence. The word learning task was followed by a test of each student's acquisition of the grapheme‐phoneme correspondences that appeared in the word stimuli. The ability to induce the relationships was found to be much more strongly related to reading ability than receptive vocabulary. The results suggest that good and poor readers applied different word learning strategies, with good readers appearing to apply more readily a principled solution and poor readers an associative solution. The results are consistent with the theory of reading acquisition advanced by Gibson and Levin.     

Fast and slow namers: benefits of segmentation and whole word training.

Poor readers in Grade 2 (mean age 7 years 7 months) were categorized into fast and slow namer groups based on their performance on a Rapid Automatized Naming (RAN) task. The fast and slow groups were then trained to read words using 3 different training regimes: one that taught onset/rime segmentation, one that taught phonemic segmentation, and one that used whole word repetition. The main results were that the slow namers acquired the words more slowly across experiences than the fast namers, irrespective of training condition, but they were particularly disadvantaged when trained with word-level units. Unlike beginning nonreaders, poor Grade 2 readers showed poorer retention following onset/rime training compared with phoneme or word level training, even when final level of learning was controlled. Further, they showed the best generalization to reading new words and nonwords following phoneme training and the worst following whole word training, even when final level of acquisition was controlled. The data are related to the P. G. Bowers and M. Wolf (1993, Reading and Writing, 5, 69-85) double-deficit hypothesis and to the specific deficits associated with early reading failure.     

ORTHOGRAPHIC REPRESENTATION AND PHONEMIC SEGMENTATION IN SKILLED READERS:

Abstract— The long-lasting effect of reading experience in Hebrew and English on phonemic segmentation was examined in skilled readers Hebrew and English orthographies differ in the way they represent phonological information Whereas each phoneme in English is represented by a discrete letter, in un-pointed Hebrew most of the vowel information is not conveyed by the print, and, therefore, a letter often corresponds to a CV utterance (i. e., a consonant plus a vowel) Adult native speakers of Hebrew or English, presented with words consisting of a consonant, a vowel, and then another consonant, were require to delete the first "sound" of each word and to pronounce the remaining utterance as fast as possible Hebrew speakers deleted the initial CV segment instead of the initial consonant more often than English speakers, for both Hebrew and English words Moreover, Hebrew speakers were significantly slower than English speakers in correctly deleting the initial phoneme, and faster in deleting the whole syllable. These results suggest that the manner in which orthography represents phonology not only affects phonological awareness during reading acquisition, but also has a long-lasting effect on skilled readers' intuitions concerning the phonological structure of their spoken language.     

Identification times for phonemic components of graded complexity and for spelling of speech

Identification time was measured for targets in speech in terms of the number of phonemes occurring between the target and response. Auditory targets in the mam experiment were at three levels of phonetic complexity; (1) monosyllabic words or nonsense syllables, each containing four phonemes; (2) clusters (vowel + consonant) consisting of the second and third phonemes within these syllables; (3) individual phonemes within these clusters. Identification time was always shorter for (1) than for (2) or (3). The effect of semantic and grammatical context upon identification was small. Plosive consonants which did not begin a syllable generally could not be identified as isolated phonemic targets, although they could be identified readily as part of a cluster. Letter targets corresponding to the spelling of the auditory stimulus permitted identification of plosive consonants, and in general followed different rules than the phonemic targets. Additional observations concerning individual targets were made.     

The spread of the phonological neighborhood influences spoken word recognition

In three experiments, the processing of words that had the same overall number of neighbors but varied in the spread of the neighborhood (i.e., the number of individual phonemes that could be changed to form real words) was examined. In an auditory lexical decision task, a naming task, and a same-different task, words in which changes at only two phoneme positions formed neighbors were responded to more quickly than words in which changes at all three phoneme positions formed neighbors. Additional analyses ruled out an account based on the computationally derived uniqueness points of the words. Although previous studies (e.g., Luce & Pisoni, 1998) have shown that the number of phonological neighbors influences spoken word recognition, the present results show that the nature of the relationship of the neighbors to the target word--as measured by the spread of the neighborhood--also influences spoken word recognition. The implications of this result for models of spoken word recognition are discussed.     

The role of phonemes and syllables in the perceived similarity of speech sounds for children

In two experiments, we investigated the factors that influence the perceived similarity of speech sounds at two developmental levels. Kindergartners and second graders were asked to classify nonsense words, which were related by syllable and phoneme correspondences. The results support the existence of a developmental trend toward increased attention to individual phonemic segments. Moreover, one significant factor in determining the perceived similarity of speech sounds appears to be the position of the component correspondences; attention to the beginning of utterances may have developmental priority. An unexpected finding was that the linguistic status of the unit involved in a correspondence (whether it was a syllable or a phoneme) did not seem particularly important. Apparently, the factors which contribute to the perceived similarity of speech sounds in the classification task are not identical to those which underlie performance in explicit segmentation and manipulation tasks, since in the latter sort of task, syllables are more accessible than phonemes for young children. The present task may tap a level of processing that is closer to the one entailed in word recognition and lexical access.     

Onsets and rimes as units of spoken syllables: evidence from children

The effects of syllable structure on the development of phonemic analysis and reading skills were examined in four experiments. The experiments were motivated by theories that syllables consist of an onset (initial consonant or cluster) and a rime (vowel and any following consonants). Experiment 1 provided behavioral support for the syllable structure model by showing that 8-year-olds more easily learned word games that treated onsets and rimes as units than games that did not. Further support for the cohesiveness of the onset came from Experiments 2 and 3, which found that 4- and 5-year-olds less easily recognized a spoken or printed consonant target when it was the first phoneme of a cluster than when it was a singleton. Experiment 4 extended these results to printed words by showing that consonant-consonant-vowel nonsense syllables were more difficult for beginning readers to decode than consonant-vowel-consonant syllables.     

The relation between phonological awareness and working memory

Previous research has failed to show a relation between children's working memory and performance on the phonological sound categorization task (M. J. Snowling, C. Hulme, A. Smith, & J. Thomas, 1994). However, the test used to assess working memory in that experiment was more comparable to a short-term memory task, which assesses storage capacity, than to a working memory task, which has both storage and processing components. In the present study, we compared the predictive power of both types of memory tasks on 2 measures of phonological awareness, the sound categorization task and a phoneme deletion task, in 7- and 8-year-olds (mean age = 8 years 1 month). The children's reading ability was also assessed. Fixed-order multiple-regression analyses showed that the sound categorization task has a higher working memory demand than the phoneme deletion task: Working memory predicted independent variance in performance only on the sound categorization task. The short-term memory task did not account for significant independent variance in performance on either of the measures of phonological awareness.     

Initial phonemes are detected faster in spoken words than in spoken nonwords

In two experiments, subjects monitored sequences of spoken consonant-vowel-consonant words and nonwords for a specified initial phoneme. In Experiment I, the target-carrying monosyllables were embedded in sequences in which the monosyllables were all words or all nonwords. The possible contextual bias of Experiment I was minimized in Experiment II through a random mixing of target-carrying words and nonwords with foil words and nonwords. Target-carrying words were distinguished in both experiments from target-carrying nonwords only in the final consonant, e.g., /bit/ vs. /bip/. In both experiments, subjects detected the specified consonant /b/ significantly faster when it began a word than when it began a nonword. One interpretation of this result is that in speech perception lexical information is accessed before phonological information. This interpretation was questioned and preference was given to the view that the result reflected processes subsequent to perception: words become available to awareness faster than nonwords and therefore provide a basis for differential responding that much sooner.     

Probabilistic Phonotactics as a Cue for Recognizing Spoken Cantonese Words in Speech

Previous experimental psycholinguistic studies suggested that the probabilistic phonotactics information might likely to hint the locations of word boundaries in continuous speech and hence posed an interesting solution to the empirical question on how we recognize/segment individual spoken word in speech. We investigated this issue by using Cantonese language as a testing case in the present study. A word-spotting task was used in which listeners were instructed to spot any Cantonese word from a series of nonsense sound sequences. We found that it was easier for the native Cantonese listeners to spot the target word in the nonsense sound sequences with high transitional probability phoneme combinations than those with low transitional probability phoneme combinations. These results concluded that native Cantonese listeners did make use of the transitional probability information to recognize the spoken word in speech.