Verbal Short-term Memory and Vocabulary Learning in Polyglots

Polyglot and non-polyglot Italian subjects were given tests assessing verbal (phonological) and visuo-spatial short-term and long-term memory, general intelligence, and vocabulary knowledge in their native language. Polyglots had a superior level of performance in verbal short-term memory tasks (auditory digit span and nonword repetition) and in a paired-associate learning test, which assessed the subjects' ability to acquire new (Russian) words. By contrast, the two groups had comparable performance levels in tasks assessing general intelligence, visuo-spatial short-term memory and learning, and paired-associate learning of Italian words. These findings, which are in line with neuropsychological and developmental evidence, as well as with data from normal subjects, suggest a close relationship between the capacity of phonological memory and the acquisition of foreign languages.     

Individual differences in phonological learning and verbal STM span

A relationship between phonological short-term memory tasks (e.g., nonword repetition, digit span) and vocabulary learning in both experimental and real-life conditions has been reported in numerous studies. A mechanism that would explain this correlation is, however, not known. The present study explores the possibility that it is the quality of phonological representations that affects both short-term recall and long-term learning of novel wordlike items. In Experiment 1, groups with relatively good and poor span for pseudowords were established. The good group was found to perform better at explicit memory tasks tapping the incidental learning of a limited stimulus pool used in an auditory immediate serial pseudoword recall task. In Experiment 2, the results of Experiment 1 were replicated when experience of correct recall was controlled. In Experiment 3, the immediate recall performance of the good group was found to benefit more than that of the poor group from syllable repetition within stimulus pools. It is concluded that the efficiency of a process that creates phonological representations is related both to short-term capacity for verbal items, and to long-term phonological learning of the structure of novel phonological items.     

Is nonword repetition a test of phonological memory or long-term knowledge? It all depends on the nonwords

The extent to which children's performance on tests of nonword repetition is constrained by phonological working memory and long-term lexical knowledge was investigated in a longitudinal study of 70 children tested at 4 and 5 years of age. At each time of testing, measures of nonword repetition, memory span, and vocabulary knowledge were obtained. Reading ability was also assessed at 5 years. At both ages, repetition accuracy was greater for nonwords of high- rather than low-rated wordlikeness, and memory-span measures were more closely related to repetition accuracy for the low-wordlike than for the high-wordlike stimuli. It is argued that these findings indicate that nonword repetition for unwordlike stimuli is largely dependent on phonological memory, whereas repetition for wordlike items is also mediated by long-term lexical knowledge and is therefore less sensitive to phonological memory constraints. Reading achievement was selectively linked with earlier repetition scores for low-wordlike nonwords, suggesting a phonological memory contribution in the early stages of reading development. Vocabulary knowledge was associated with repetition accuracy for both low- and high-wordlike nonwords, consistent with the notion that lexical knowledge and nonword repetition share a reciprocal developmental relationship.     

A developmental deficit in short-term phonological memory: Implications for language and reading

Abstract

QU, an eight-year-old boy, was identified from a large scale normative study on the basis of his greatly reduced digit span, combined with normal long-term memory and non-verbal intelligence. Further investigation indicated that his visual STM was normal, but that he was clearly impaired on two verbal STM tests, nonword repetition, and memory span for words. His span showed clear effects of phonological similarity and word-length, suggesting qualitatively normal functioning of the phonological loop component of working memory, despite a quantitative impairment in level of performance. This pattern resembles that found in an earlier study of children with a specific language disorder. We tested QU on measures of vocabulary, syntax, and reading, and found him to be substantially below the age norms on all three. The implications of these findings are discussed for the role of the phonological loop in language development.     

Nonword repetition in specific language impairment: More than a phonological short-term memory deficit

The possible role of phonological short-term memory in the nonword repetition deficit of children with specific language impairment (SLI) was investigated in a study comparing serial recall and nonword repetition of sequences of auditorily presented CV syllables. The SLI group showed impairments in both serial recall and nonword repetition relative to typically developing children of the same age, however the SLI deficit in nonword repetition was greater and persisted even when differences on an independent measure of short-term memory were taken into account. These findings cannot be readily explained in terms of a sole deficit in short-term memory, and point instead to differences between the serial recall and nonword repetition paradigms as potential factors contributing to this disorder of learning.     

Contrasting contributions of phonological short-term memory and long-term knowledge to vocabulary learning in a foreign language

The contributions of phonological short-term memory and existing foreign vocabulary knowledge to the learning of new words in a second language were compared in a sample of 40 Greek children studying English at school. The children's speed of learning new English words in a paired-associate learning task was strongly influenced by their current English vocabulary, but was independent of phonological memory skill, indexed by nonword repetition ability. However, phonological memory performance was closely linked to English vocabulary scores. The findings suggest that in learners with considerable familiarity with a second language, foreign vocabulary acquisition is mediated largely by use of existing knowledge representations.     

语音短时记忆与词汇知识对第二语言词汇学习的影响

选取两种语音熟悉程度不同的非词为实验材料,把语音短时记忆区分为项目短时记忆和序列短时记忆,考察语音短时记忆与词汇知识对汉英双语者第二语言（英语）词汇学习的影响。实验1采用产出性的方式进行学习,结果发现,词汇知识与项目短时记忆对语音熟悉非词的学习起预测作用;词汇知识与序列短时记忆对语音不熟悉非词学习起预测作用。实验2采用接受性的方式进行学习,结果发现,项目短时记忆、序列短时记忆和词汇知识都对语音熟悉非词学习起独立的预测作用;项目短时记忆和序列短时记忆对语音不熟悉非词学习起独立的预测作用。实验结果表明,语音短时记忆和词汇知识都是影响英语词汇学习的重要因素。具体而言,学习语音熟悉的词汇,词汇知识起着更为重要的作用;学习语音不熟悉的词汇,语音短时记忆、特别是序列短时记忆起着更为重要的作用,而且两者作用的大小随着词汇学习方式的不同而发生变化。     

The Effects of Cognitive: Linguistic Variables and Language Experience on Behavioural and Kinematic Performances in Nonword Learning

The aim of the present study was to investigate the effects of cognitive-linguistic variables and language experience on behavioral and kinematic measures of nonword learning in young adults. Group 1 consisted of thirteen participants who spoke American English as the first and only language. Group 2 consisted of seven participants with varying levels of proficiency in a second language. Logistic regression of the percent of correct productions revealed short-term memory to be a significant contributor. The bilingual group showed better performance compared to the monolinguals. Linear regression of the kinematic data revealed that the short-term memory variable contributed significantly to movement coordination. Differences were not observed between the bilingual and the monolingual speakers in kinematic performance. Nonword properties including syllable length and complexity influenced both behavioral and kinematic performance. The findings supported the observation that nonword repetition is multiply determined in adults.     

Hebb learning, verbal short-term memory, and the acquisition of phonological forms in children

Recent work using the Hebb effect as a marker for implicit long-term acquisition of serial order has demonstrated a functional equivalence across verbal and visuospatial short-term memory. The current study extends this observation to a sample of five- to six-year-olds using verbal and spatial immediate serial recall and also correlates the magnitude of Hebb learning with explicit measures of word and nonword paired-associate learning. Comparable Hebb effects were observed in both domains, but only nonword learning was significantly related to the magnitude of Hebb learning. Nonword learning was also independently related to individuals' general level of verbal serial recall. This suggests that vocabulary acquisition depends on both a domain-specific short-term memory system and a domain-general process of learning through repetition.     

Contrasting contributions of phonological short‐term memory and long‐term knowledge to vocabulary learning in a foreign language

The contributions of phonological short‐term memory and existing foreign vocabulary knowledge to the learning of new words in a second language were compared in a sample of 40 Greek children studying English at school. The children's speed of learning new English words in a paired‐associate learning task was strongly influenced by their current English vocabulary, but was independent of phonological memory skill, indexed by nonword repetition ability. However, phonological memory performance was closely linked to English vocabulary scores. The findings suggest that in learners with considerable familiarity with a second language, foreign vocabulary acquisition is mediated largely by use of existing knowledge representations.     

The role of short-term memory in semantic priming.

Two theories of priming were compared: spreading activation theories, in particular ACT, and compound-cue theories. Whereas ACT assumes that priming is a result of diffusing activation in long-term memory, compound-cue models suggest that priming results from a formation process of prime and target in short-term memory. Thirty-eight participants took part in a study that combined a digit span task with a double lexical decision task consisting of a prime and a target item. Digit span length (low, medium, and high) and prime type (related or unrelated word or nonword) were both within-subject variables. As expected, results showed significant priming effects. In favor of ACT, no interaction between digit span length and prime type was found. Additionally, a nonword inhibition effect (unrelated versus nonword prime) was found, which was predicted by compound-cue theories. This finding is discussed in terms of the process interference and response competition hypotheses.     

Learning to read changes children's phonological skills: evidence from a latent variable longitudinal study of reading and nonword repetition

Individual differences in nonword repetition are associated with language and literacy development, but few studies have considered the extent to which learning to read influences phonological skills as indexed by nonword repetition performance. We explored this question using a latent variable longitudinal design. Reading, oral language and nonword repetition were assessed in 215 children at age 6 years and one year later at age 7. Reading at 6 years predicted growth in nonword repetition between 6 and 7 years, independent of the effects of oral language skills and the autoregressive effect of nonword repetition at 6 years, but nonword repetition was not a longitudinal predictor of the growth of reading. These findings demonstrate that learning to read has a powerful effect on children's language processing systems. We consider how learning to read might influence speech processing, and discuss the implications of our findings for theoretical accounts of reading disorder.     

The Role of Short-Term Memory in Semantic Priming

Two theories of priming were compared: spreading activation theories, in particular ACT* (J. R. Anderson, 1983), and compound-cue theories (R. Ratcliff & G. McKoon, 1988). Whereas ACT* assumes that priming is a result of diffusing activation in long-term memory, compound-cue models suggest that priming results from a formation process of prime and target in short-term memory. Thirty-eight participants took part in a study that combined a digit span task with a double lexical decision task consisting of a prime and a target item. Digit span length (low, medium, and high) and prime type (related or unrelated word or nonword) were both within-subject variables. As expected, results showed significant priming effects. In favor of ACT*, no interaction between digit span length and prime type was found. Additionally, a nonword inhibition effect (unrelated versus nonword prime) was found, which was predicted by compound-cue theories. This finding is discussed in terms of the process interference and response competition hypotheses.     

Lexical and sublexical knowledge influences the encoding,storage, and articulation of nonwords

Nonword repetition (NWR) has been used extensively in the study of child language. Although lexical and sublexical knowledge is known to influence NWR performance, there has been little examination of the NWR processes (e.g., encoding, storage, and articulation) that may be affected by lexical and sublexical knowledge. We administered two- and three-syllable spoken nonword recognition and nonword repetition tests on two independent groups of 31 children (mean age = 5 years 7 months). Spoken nonword recognition primarily involves encoding and storage, whereas NWR involves an additional articulation process. The influence of lexical and sublexical knowledge was determined by examining the number of lexical errors produced. There was clear involvement of long-term lexical and sublexical knowledge in both spoken nonword recognition and NWR. In spoken nonword recognition, twice as many errors involved selecting a foil that contained a lexical item (e.g., ‘yashukup’) as involved selecting a foil that contained only nonsense syllables (e.g., ‘yashunup’). In repetition, over 30% of errors changed a nonsense syllable to a lexical item. Our results show that long-term lexical and sublexical knowledge is pervasive in NWR. Any explanation of NWR performance must therefore consider the influence of lexical and sublexical knowledge throughout the whole repetition process, from the encoding to the articulation of nonwords.     

Processing efficiency in preschoolers’ memory span: Individual differences related to age and anxiety

In self-paced auditory memory span tasks, the microanalysis of response timing measures represents a developmentally sensitive measure, providing insights into the development of distinct processing rates during recall performance. The current study first examined the effects of age and trait anxiety on span accuracy (effectiveness) and response timing (efficiency) measures from word and digit span performance in a preschool sample (N = 76, mean age = 57 months, SD = 11). Children were reassessed 8 months later using the same two tasks plus a test of nonword memory span and a measure of articulation rate. The results at the second time point (T2) confirmed the effects of age on both processing effectiveness and efficiency. Trait anxiety was an additional negative predictor of span effectiveness (especially for digit span) and efficiency (in the case of word and nonword span). The findings are discussed in the context of factors contributing to early short-term memory development and attentional control theory.     

Implicit statistical learning in language processing: Word predictability is the key

Fundamental learning abilities related to the implicit encoding of sequential structure have been postulated to underlie language acquisition and processing. However, there is very little direct evidence to date supporting such a link between implicit statistical learning and language. In three experiments using novel methods of assessing implicit learning and language abilities, we show that sensitivity to sequential structure – as measured by improvements to immediate memory span for structurally-consistent input sequences – is significantly correlated with the ability to use knowledge of word predictability to aid speech perception under degraded listening conditions. Importantly, the association remained even after controlling for participant performance on other cognitive tasks, including short-term and working memory, intelligence, attention and inhibition, and vocabulary knowledge. Thus, the evidence suggests that implicit learning abilities are essential for acquiring long-term knowledge of the sequential structure of language – i.e., knowledge of word predictability – and that individual differences on such abilities impact speech perception in everyday situations. These findings provide a new theoretical rationale linking basic learning phenomena to specific aspects of spoken language processing in adults, and may furthermore indicate new fruitful directions for investigating both typical and atypical language development.     

Cross‐Linguistic Differences in Digit Memory Span

This study investigated whether the better performance of the Chinese in digit memory span tasks was due only to the shorter pronunciation duration of Chinese digit names, or to enhanced visuospatial sketchpad abilities, or to both. Results of the experiment showed that the Chinese outperformed their Malay counterparts in digit memory span tasks because Chinese digit names had shorter pronunciation durations than Malay digit names and not because the Chinese had better visuospatial sketchpad abilities than the Malays. The results thus support Baddeley's phonological loop hypothesis as an account for cross‐linguistic differences in digit memory spans. Because memory traces are subject to decay and the phonological store is temporally limited, the shorter the pronunciation duration of digit names in a language, the more digits one can rehearse within a limited time period, and therefore the larger is one's short‐term digit span in that language.     

词汇语音学习的影响因素

摘要 词汇语音的学习受哪些因素的影响是心理语言学研究中一个重要的问题。语音回路理论认为,语音短时记忆在词汇语音的学习过程中发挥着关键性的作用,语音短时记忆能力越好越有助于词汇的学习;语音敏感性假说认为,语音意识是影响儿童词汇发展及学习的重要因素;另外一些研究者认为,语音知识可能发挥着更为基础和关键的作用,最近的研究则更加强调几种因素如何相互作用影响词汇语音的学习。本文最后提出了该领域需要进一步研究的问题。     

Short-term memory and sentence processing: Evidence from neuropsychology

Traditional models of memory assume that short-term memory, as measured by memory span, plays an important role in linguistic processing and the learning ofverbal information. Contradicting this view are findings from a brain-damaged patient, E.A., who, despite a verbal memory span of about two items, demonstrated normal sentence comprehension in a variety oftasks. She was, however, impaired whenever verbatim phonological information had to be maintained or learned. These results and those from other patients with reduced span suggest that the phonological storage capacity that is critical to memory span plays only a limited role in language processing, specifically in the maintenance and learning of phonological forms. Implications for models of short-term memory are discussed. It is argued that short-termmemory should be seen as deriving from the processing and retentive capacities of language processing modules, with span tasks drawing on only a subset of these modules.     

Diversity not quantity in caregiver speech: Using computational modeling to isolate the effects of the quantity and the diversity of the input on vocabulary growth

Children who hear large amounts of diverse speech learn language more quickly than children who do not. However, high correlations between the amount and the diversity of the input in speech samples makes it difficult to isolate the influence of each. We overcame this problem by controlling the input to a computational model so that amount of exposure to linguistic input (quantity) and the quality of that input (lexical diversity) were independently manipulated. Sublexical, lexical, and multi-word knowledge were charted across development (Study 1), showing that while input quantity may be important early in learning, lexical diversity is ultimately more crucial, a prediction confirmed against children’s data (Study 2). The model trained on a lexically diverse input also performed better on nonword repetition and sentence recall tests (Study 3) and was quicker to learn new words over time (Study 4). A language input that is rich in lexical diversity outperforms equivalent richness in quantity for learned sublexical and lexical knowledge, for well-established language tests, and for acquiring words that have never been encountered before.