Balancing bilinguals: lexical-semantic production and cognitive processing in children learning Spanish and English.

The present study investigated developmental changes in lexical production skills in early sequential bilinguals, in both Spanish (L1) and English (L2), exploring the effects of age, years of experience, and basic-level cognitive processing (specifically the ability to resist interference) within a timed picture-naming task. To assess resistance to interference, naming was compared in low competition (blocked-single language) vs. high competition (mixed-alternating language) conditions. Participants were 100 individuals, 20 at each of 5 different age levels (5-7, 8-10, 11-13, 14-16, & young adults). All had learned Spanish as a first language in the home, with formal English experience beginning at 5 years. Gains were made in both languages across age. However, there was a developmental crossover from Spanish dominance in the youngest children, through a period of relatively balanced Spanish and English skills in middle childhood, culminating in a clear pattern of English dominance among adolescents and young adults. Although all groups experienced a greater slowing of response times in the mixed-language condition relative to the blocked-language condition, developmental changes in the pattern of speed-accuracy trade-offs in the mixed condition can be interpreted to reflect a change in the ability to resist cognitive interference during word production.     

Third graders' metalinguistic skills, reading skills, and stress production in derived English words.

PURPOSE: This study examined relationships between 3rd graders' metalinguistic skills (phonological and morphological awareness), reading skills (decoding and word identification), and accurate stress production in derived words with stress-changing suffixes. METHOD: Seventy-six typically developing 3rd-grade children (M=8;8[years;months]) participated in a battery of tests measuring general oral language ability, phonological and morphological awareness skills, reading skills, and derived word production. RESULTS: Significant positive correlations between stress accuracy in derived words and all other measures were found. Two multiple regressions were run, one with stress accuracy as the outcome variable and the other with decoding as the outcome variable. Metalinguistic and decoding skills independently accounted for a significant proportion of the variance in derived word stress production beyond that accounted for by age and general oral language ability. When decoding was the outcome variable, accurate stress production explained a significant amount of variance (11%) after phonological and morphological awareness were controlled. CONCLUSION: The relationship between accurate stress production and decoding appears to be strong and bidirectional. Possibly, the stress accuracy measure taps into another level of phonological awareness (i.e., morphophonological awareness), which develops later than typical segmental measures of phonological awareness.     

Balancing bilinguals II: lexical comprehension and cognitive processing in children learning Spanish and English.

The present study investigated developmental changes in lexical comprehension skills in early sequential bilinguals, in both Spanish (L1) and English (L2), exploring the effects of age, years of experience, and basic-level cognitive processing (specifically the ability to maintain performance during mixed vs. single-language processing) within a timed picture-word verification task. Participants were 100 individuals, 20 at each of five different age levels (ages in years, 5-7, 8-10, 11-13, 14-16, and adults). All had learned Spanish as a first language in the home, with formal English experience beginning at 5 years. Gains (as indexed by increased response speed) were made in both languages across age, although these gains were greater in English than in Spanish. The youngest participants were relatively "balanced" in their crosslinguistic performance. By middle childhood, performance was better in English. There were no response decrements at any age between the mixed and single-language processing conditions. These results are compared to those from a previous study that investigated basic-level lexical production in developing Spanish-English bilinguals. Both studies show a move toward English dominance in middle childhood, but the transition occurs earlier in comprehension. The production study showed differences between mixed and single-language processing (reflecting potential interlanguage interference) that are not evident in comprehension.     

Normal and learning disabled children's central auditory processing skills: an experimental test battery

The performance of normal children (N = 13) and learning disabled children (N = 26) on an experimental battery of central auditory processing (CAP) tasks was examined. The battery included low-pass filtered speech (LPFS), binaural fusion (BF), time-compressed speech (TC), and dichotic monosyllables (DM) tests. The learning disabled subjects were classified as having normal (LD/N) or significantly impaired (LD/LD) auditory perceptual skills on the basis of a pretest battery of auditory language tests. The normal (N/N) subjects and nonauditory learning disabled (LD/N) subjects tended to perform alike across measures. The auditorily impaired (LD/LD) subjects tended to perform significantly poorer than their normal agemates. The results emphasized the heterogeneity of the learning disabled population. In addition, the results suggested a potentially useful "at risk" criterion when a CAP test battery is used in the assessment of auditory perceptual impairment among children.     

African American preschoolers' language, emergent literacy skills, and use of African American English: a complex relation.

PURPOSE: This study examined the relation between African American preschoolers' use of African American English (AAE) and their language and emergent literacy skills in an effort to better understand the perplexing and persistent difficulties many African American children experience learning to read proficiently. METHOD: African American preschoolers' (n = 63) vocabulary skills were assessed in the fall and their language and emergent literacy skills were assessed in the spring. The relation between students' AAE use and their vocabulary and emergent literacy skills was examined using hierarchical linear modeling (HLM), controlling for fall vocabulary and other child, family, and school variables. Children's use of AAE was examined across two contexts-sentence imitation and oral narrative using a wordless storybook prompt. RESULTS: There was a significant -shaped relation between the frequency with which preschoolers used AAE features and their language and emergent literacy skills. Students who used AAE features with greater or lesser frequency demonstrated stronger sentence imitation, letter-word recognition, and phonological awareness skills than did preschoolers who used AAE features with moderate frequency, controlling for fall vocabulary skills. Fewer preschoolers used AAE features during the sentence imitation task with explicit expectations for Standard American English (SAE) or School English than they did during an oral narrative elicitation task with implicit expectations for SAE. CONCLUSIONS: The nonlinear relation between AAE use and language and emergent literacy skills, coupled with systematic differences in AAE use across contexts, indicates that some preschoolers may be dialect switching between AAE and SAE, suggesting emerging pragmatic/metalinguistic awareness.     

Human efferent adaptation of DPOAEs in the L1,L2 space

The adaptive properties of distortion product otoacoustic emissions (DPOAEs) at 2f(1)-f2 were investigated in 12 ears of normally hearing adults aged 18-30 years using long-lasting 1-s primary-tone on-times. In this manner, DPOAE adaptation at a single f2 of 1.55 kHz (f2/f1=1.21) was evaluated as a function of the levels of the primary tones in a matrix of L1, L2 settings, which varied from 45 to 80 dB SPL, in 5-dB steps. DPOAEs were elicited under both monaural and binaural stimulus-presentation conditions. Adaptation was defined as the difference in DPOAE levels between the initial 92-ms baseline measure using a standard protocol and one obtained during the final 92 ms of the prolonged 1-s primary-tones. These differences were averaged across subjects to create contour plots of mean adaptation in the L1,L2 space. The 2f(1)-f2 DPOAE revealed consistent regions of suppression (-0.5 dB difference) or enhancement (+0.5 dB difference) with respect to baseline measures within the L(1),L(2) matrix for both acoustic-stimulation conditions. Specifically, 2f(1)-f2 DPOAE suppressions of 1-2 dB occurred for both monaural and binaural presentations, typically at level combinations in which L1>L2. In contrast, larger 2f(1)-f2 DPOAE enhancements of 3-4 dB occurred for only the binaural condition, at primary-tone level combinations where L1相似文献   

Observational learning of comprehension monitoring skills in children who exhibit mental retardation

An observational learning paradigm was used to instruct 5 children with mild or moderate mental retardation to monitor their comprehension of inadequate instructions. Instructions were inadequate because of an interfering signal, an unfamiliar word, excessive length, or an unfamiliar idiomatic phase. Subjects' peers served as models during the training. A multiple baseline design across subjects and across instruction types was employed. All subjects learned to request clarification of the first three inadequate instructions; however, none of the children learned to request clarification of idiomatic phrases. Although all children eventually demonstrated observational learning, three children required feedback from the trainer before they began to request clarification for one or two of the instruction types. Two children generalized their requesting behavior to the interfering signal message type, suggesting that generalization may be likely to occur between similar message types. During posttesting all children generalized their requesting behavior when presented with two unfamiliar message types, sometimes using new question forms. Four of the 5 children also generalized their requesting behavior in sessions with their teachers 5-10 weeks later.     

Central auditory skills in blind and sighted subjects.

Three different central auditory skills were compared and evaluated in 56 blind and 40 sighted subjects. The study consisted of three experiments conducted in three subgroups. Experiment A was performed in order to evaluate the localization function; experiment B for the temporal auditory resolution ability of the blind adult, and experiment C to test the ability of the blind person to discriminate speech material in noise. In all three experiments the blind subjects obtained significantly better results than the sighted subjects. From these results it was concluded that there is supporting evidence of a certain superiority of the blind individual with regard to central auditory function.     

Language skills of children and adolescents with Down syndrome: I. Comprehension.

This study investigates the development of vocabulary and syntax comprehension skills cross-sectionally in 48 children and adolescents with Down syndrome (Trisomy 21), aged 5-20 years, in comparison to 48 control children aged 2-6 years matched statistically for nonverbal mental age and mother's years of education. Age-equivalent scores on vocabulary (PPVT-R) and syntax (TACL-R) comprehension tests differed in the Down syndrome group but not the control group; vocabulary comprehension was relatively more advanced than syntax. Age-equivalent scores on nonverbal cognitive subtests of pattern analysis and short-term memory for bead arrangements (Stanford-Binet, 4th ed.) also differed for the Down syndrome group but not the control group, indicating an unusual pattern of nonverbal cognitive function in the Down syndrome group. Stepwise multiple regression analyses showed that chronological age and mean mental age, collectively, accounted for 78% of the variability in vocabulary comprehension and 80% of the variability in syntax comprehension in the Down syndrome group, with total passes on a hearing screening accounting for an additional 4% in each case. Implications for research are discussed.     

初始音强度差对听力正常青年人畸变产物耳声发射的影响

目的 探讨初始音强度差对听务正常青年人畸变产物耳声发射（ＤＰＯＡＥ）幅值的影响,为临床应用ＤＰＯＡＥ提供最佳的刺激强度组合。方法 用ＩＨＳ Ｖｅｒｓｉｏｎ ３．２型耳声发射仪对听务正常青年人３９耳进行了ＤＰＯＡＥ测试,分别记录Ｌ１为７５,６５,５５ｄＢ ＳＰＬ,强度差Ｌ１－Ｌ２为０,５,１０,１５,ｄＢ ＳＰＬ时,不同Ｌ１－Ｌ２值对ＤＰＯＡＥ幅值的影响。     

Fast mapping skills in the developing lexicon.

PURPOSE: This preliminary investigation was a longitudinal study of fast mapping skills in normally developing children, 16-18 months of age. The purpose was to examine the effects of practice on the accessibility of words in lexical memory. METHOD: Eight children were taught the names of 24 unfamiliar objects over 12 weekly training sessions. The amount of practice children had with individual words varied as a function of session. Data were compared to a control group of children-matched on productive vocabulary-who were exposed to the same experimental words at the first and last sessions only. RESULTS: The results showed that for children in the experimental group, extended practice with a novel set of high-practice words led to the rapid acquisition of a second set of low-practice words. Children in the control group did not show the same lexical advantage. CONCLUSIONS: The data suggest that learning some words primes the system to learn more words. Vocabulary development can thus be conceptualized as a continual process of fine-tuning the lexical system to enable increased accessibility to information. Implications for the treatment of children with word-finding difficulties are considered.     

Distortion-product otoacoustic emissions (DPEs) in neonates: frequency ratio (F2/F1) and stimulus level differences (L1-L2).

Stimulus parameter values for distortion-product otoacoustic emissions (DPE) recordings in neonates are based on adult studies. The purpose of the present investigation was to determine what values of stimulus frequency ratio (F2/F1) and stimulus level difference (L1-L2) produced the largest DPE amplitude in neonates. Single ear DPE measurements were obtained from 11 preterm neonates (34-36 weeks post-conceptual age) at F2s of 2, 3, and 4 kHz. Ratio sweeps were performed through a frequency range determined by F2/F1 = 1.4-1.02 at L1-L2s of 0, 5, 10, 15 and 20 dB, where L1 = 65 dB SPL. The findings indicated that on average, an L1-L2 = 5 dB and an F2/F1 = 1.18 produced the largest DPE amplitude across all F2s.     

Lifelong learning in otolaryngology: self-directed learning

Although nothing in didactic form approaches the learning experience of the real world, the educational process up to graduation is based on a teacher-directed model of learning. Active engagement in self-planned learning activities tends to be more effective than passive learning. Lifelong learning involves finding and implementing solutions to everyday problems encountered in the clinic, emergency room, and operating room and on the wards. The process by which much of this education occurs is via self-directed learning, in which learners challenge themselves to pursue activities that arise from their own experiences using their own emerging styles. The acquisition of self-directed learning is a complex process that involves numerous skills and competencies relied upon to complete challenges.     

Communication skills in pediatric cochlear implant recipients.

Detailed longitudinal studies of speech perception, speech production and language acquisition have justified a significant change in the demographics of congenitally and prelingually deaf children who receive cochlear implants. A trend toward earlier cochlear implantation has been justified by improvements in measures assessing these areas. To assess the influence of age at implantation on performance, age 5 years was used as a benchmark. Thirty-one children who received a Nucleus cochlear implant and use the SPEAK speech processing strategy and two children who received a Clarion cochlear implant and use the CIS strategy served as subjects. The subjects were divided into three groups based on age at implantation. The groups comprised children implanted before the age of 3 years (n = 14), children implanted between 3 years and 3 years 11 months (n = 11) and those implanted between 4 years and 5 years 3 months (n = 8). The children were further divided according to whether they used oral or total communication. The earlier-implanted groups demonstrated statistically significant improvements on measures of speech perception. Improvements in speech intelligibility as a function of age at implant were seen but did not reach statistical significance. The results of the present study demonstrate that early implantation promotes the acquisition of speaking and listening skills.