The interplay between language, gesture, and affect during communicative transition: A dynamic systems approach.

From a dynamic systems perspective, transition points in development are times of increased instability, during which behavioral patterns are susceptible to temporary decoupling. This study investigated the impact of the vocabulary spurt on existing patterns of communicative coordination. Eighteen typically developing infants were videotaped at home 1 month before, at, and after the vocabulary spurt. Infants were identified as spurters if they underwent a discrete phase transition in vocabulary development (marked by an inflection point), and compared with a group of nonspurters whose word-learning rates followed a trajectory of continuous change. Relative to surrounding sessions, there were significant reductions in overall coordination of communicative behaviors and in words produced in coordination at the vocabulary spurt session for infants who experienced more dramatic vocabulary growth. In contrast, nonspurters demonstrated little change across sessions. Findings underscore the importance of transitions as opportunities for observing processes of developmental change. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Predictors of word decoding and reading fluency across languages varying in orthographic consistency.

Very few studies have directly compared reading acquisition across different orthographies. The authors examined the concurrent and longitudinal predictors of word decoding and reading fluency in children learning to read in an orthographically inconsistent language (English) and in an orthographically consistent language (Greek). One hundred ten English-speaking children and 70 Greek-speaking children attending Grade 1 were examined in measures of phonological awareness, phonological memory, rapid naming speed, orthographic processing, word decoding, and reading fluency. The same children were reassessed on word decoding and reading fluency measures when they were in Grade 2. The results of structural equation modeling indicated that both phonological and orthographic processing contributed uniquely to reading ability in Grades 1 and 2. However, the importance of these predictors was different in the two languages, particularly with respect to their effect on word decoding. The authors argue that the orthography that children are learning to read is an important factor that needs to be taken into account when models of reading development are being generalized across languages. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Rapid change in lexical development in comprehension and production.

24 infants were given word comprehension tests at 2-mo intervals from 14 to 22 mo. For each word, the child observed 2 slides and was prompted to look at 1 named by the experimenter. Visual fixation following the prompt was compared with fixation during a preprompt baseline to calculate a word comprehension score reflecting increase of attention to the referent independent of initial salience. The month-to-month change in comprehension scores revealed a spurt or surge for some but not all children, with the largest number of spurts occurring in the 20–22 mo interval. For a subset of children (n?=?18), parents maintained diaries of spoken words. For a statistically significant number of children, the presence of a comprehension spurt was associated with the presence of a production spurt. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sixteen- and 24-month-olds' use of mutual exclusivity as a default assumption in second-label learning.

The significance of the mutual exclusivity assumption for early word learning has been questioned on 2 accounts: (1) Children learn second labels for objects, which violates the assumption, and (2) evidence documenting use of mutual exclusivity comes mostly from older children. This article addresses both concerns. Use of mutual exclusivity predicts not that learning 2nd labels is impossible but that it is harder than learning 1st labels. To test this, very young children were taught novel labels for objects they either could or could not already name. In Study 1, contrary to predictions, 24-mo-olds learned 1st and 2nd labels equally well. But in Study 2, when children had an additional word to learn, they had trouble learning second (but not first) labels. Similarly, in Study 3, 16-mo-olds who were taught only one new word had trouble learning second labels. Thus, from 16 mo on, mutual exclusivity helps children interpret novel words. Yet, when their processing capacity is not overly taxed, 24-mo-olds can override this default assumption. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Sensitivity of 24-month-olds to the prior inaccuracy of the source: Possible mechanisms.

Three studies examined 24-month-olds' sensitivity to the prior accuracy of the source of information and the way in which young children modify their word learning from inaccurate sources. In Experiments 1A, 2, and 3, toddlers interacted with an accurate or inaccurate speaker who trained and tested children's comprehension of a new word–object link. In Experiment 1, children performed less systematically in response to an inaccurate than to an accurate source. In Experiments 2 and 3, after toddlers' comprehension of the new word–object links was tested by the original source, a second speaker requested the target objects. In Experiment 2, children responded randomly in response to the second speaker's requests when novel words were previously presented by an inaccurate source. In Experiment 3, toddlers responded randomly in response to both speakers in the inaccurate condition when their memory for words was taxed by a brief delay period. Taken together, these findings suggest that toddlers attend to accuracy information, that they treat inaccuracy as a feature of a particular individual, and that the word–object representations formed as a result may be fragile and short lived. Findings are discussed in terms of possible mechanisms by which children adjust their word learning from problematic speakers. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Interaction between particles and word order in the comprehension and production of simple sentences in Japanese children.

In light of studies that have emphasized the role of word order for children learning English, 4 experiments were conducted in which the comprehension, production, and imitation of simple sentences among 92 2–6 yr old Japanese children were assessed. Japanese is a language that has a dominant subject–object–verb order yet allows flexibility in word order due to postposed particles that signal grammatical role. Results across different tasks suggest that children learning Japanese show neither a strong reliance on word order nor on particles alone. Rather, they possess a bias for a matching between particles and the position in the sentence where they appear. (33 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Young children's productivity with word order and verb morphology.

Four studies examined English-speaking children's productivity with word order and verb morphology. Two- and 3-year-olds were taught novel transitive verbs with experimentally controlled argument structures. The younger children neither used nor comprehended word order with these verbs; older children comprehended and used word order correctly to mark agents and patients of the novel verbs. Children as young as 2 years 1 month added -ing but not -ed to verb stems; older children were productive with both inflections. These studies demonstrate that the present progressive inflection is used productively before the regular past tense marker and suggest that productivity with word order may be independent of developments in verb morphology. The findings are discussed in terms of M. Tomasello's (1992a) Verb Island hypothesis and M. Rispoli's (1991) notion of the mosaic acquisition of grammatical relations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Evidence for a form of mutual exclusivity during label acquisition by grey parrots (Psittacus erithacus)?

The authors present context-dependent evidence for a form of mutual exclusivity during label learning by Grey parrots (Psittacus erithacus). For human children, mutual exclusivity refers to their assumption during early word learning that an object has one and only one label. Along with the whole-object assumption (that a label likely refers to an entire object rather than some partial aspect), mutual exclusivity is thought to guide children in initial label acquisition. It may also help children overcome the whole-object assumption by helping them interpret a novel word as something other than an object label, but for young children, any second label for an object can initially be more difficult to acquire than the first. The authors show that Grey parrots quickly learn object labels for items, then have considerable difficulty learning to use color labels with respect to a previously labeled item unless specifically taught to use a color and object label as a pair. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

An effective method for building meaning vocabulary in primary grades.

Teaching vocabulary to primary grade children is essential. Previous studies of teaching vocabulary (word meanings) using story books in the primary grades reported gains of 20%-25% of word meanings taught. The present studies concern possible influences on word meaning acquisition during instruction (Study 1) and increasing the percentage and number of word meanings acquired (Study 2). Both studies were conducted in a working-class school with approximately 50% English-language learners. The regular classroom teachers worked with their whole classes in these studies. In Study 1, average gains of 12% of word meanings were obtained using repeated reading. Adding word explanations added a 10% gain for a total gain of 22%. Pretesting had no effect on gains. In Study 2, results showed learning of 41% of word meanings taught. At this rate of learning word meanings taught, it would be possible for children to learn 400 word meanings a year if 1,000 word meanings were taught. The feasibility of teaching vocabulary to primary grade children is discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Verbal learning and memory in children with fetal alcohol syndrome

Children with fetal alcohol syndrome (FAS) were administered the California Verbal Learning Test-Children's Version, a word list learning task that assesses immediate and delayed recall and recognition memory. When compared with matched control children, the children with FAS had difficulty learning and recalling the words after a delay period and tended to make an increased number of intrusion and perseverative errors. In addition, they had difficulty discriminating target words from distracter words and made more false-positive errors on recognition testing. Some of these deficits persisted even when mental age was controlled. The results suggest that children with FAS have profound verbal learning and memory deficits, and that some of these deficits cannot be accounted for even when mental age is considered. Furthermore, the results are consistent with deficits in encoding verbal information and impairment in response inhibition capabilities.     

Shared book reading: When and how questions affect young children's word learning.

Shared book reading, and the conversation that accompanies it, can facilitate young children's vocabulary growth. To identify the features of extratextual questions that help 3-year-olds learn unfamiliar words during shared book reading, two experiments explored the impact of cognitive demand level, placement, and an approximation to scaffolding. Asking questions about target words improved children's comprehension and production of word–referent associations, and children with larger vocabularies learned more than children with smaller vocabularies. Neither the demand level nor placement of questions differentially affected word learning. However, an approximation to scaffolding, in which adults asked low demand questions when words first appeared and high demand questions later, did facilitate children's deeper understanding of word meanings as assessed with a definition task. These results are unique in experimentally demonstrating the value for word learning of shifting from less to more challenging input over time. Discussion focuses on why a scaffolding-like procedure improves children's acquisition of elaborated word meanings. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Baby's first 10 words.

Although there has been much debate over the content of children's first words, few large sample studies address this question for children at the very earliest stages of word learning. The authors report data from comparable samples of 265 English-, 336 Putonghua- (Mandarin), and 369 Cantonese-speaking 8- to 16-month-old infants whose caregivers completed MacArthur-Bates Communicative Development Inventories and reported them to produce between 1 and 10 words. Analyses of individual words indicated striking commonalities in the first words that children learn. However, substantive cross-linguistic differences appeared in the relative prevalence of common nouns, people terms, and verbs as well as in the probability that children produced even one of these word types when they had a total of 1-3, 4-6, or 7-10 words in their vocabularies. These data document cross-linguistic differences in the types of words produced even at the earliest stages of vocabulary learning and underscore the importance of parental input and cross-linguistic/cross-cultural variations in children's early word-learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Young children extend novel words at the basic level: Evidence for the principle of categorical scope.

If young children approached the task of word learning with a specific hypothesis about the meaning of novel count nouns, they could make the problem of word learning more tractable. Six experiments were conducted to test children's hypotheses about how labels map to object categories. Findings indicated that (a) 3- and 4-year-olds function with an antithematic bias; (b) children do not reliably extend novel nouns to superordinate exemplars when perceptual similarity is controlled until approximately age 7; and (c) children expect novel nouns to label taxonomic categories at the basic level, even in the presence of a perceptually compelling distractor. Results are interpreted as supporting the principle of categorical scope (R. M. Golinkoff, C. B. Mervis, & K. Hirsh-Pasek; see record 1994-40565-001). (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Learning color words involves learning a system of mappings.

This research examines the difficulty children encounter when acquiring 2 specific sets of adjectives, color and size words, and suggests that children must acquire a system of mapping in learning these words. Children were assessed on 4 types of mappings (word–word maps, property–property maps, word–property maps, and word–word–property maps) by completing 3 color tasks. Children also participated in comparable tasks for size words. In Study 1, 13 two-year-olds were followed longitudinally at 3-week intervals. In Study 2, 56 two-year-olds participated in a cross-sectional replication. The results indicate that children acquire color maps in a characteristic order. Children demonstrated a different pattern of acquisition for size words. The results suggest that learning word associations may promote color word acquisition and that learning color words may promote selective attention to color. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Beyond fast mapping: Young children's extensions of novel words and novel facts.

L. Markson and P. Bloom (1997) concluded that there was evidence against a dedicated system for word learning on the basis of their finding that children remembered a novel word and a novel fact equally well. However, a word-learning system involves more than recognition memory; it must also provide a means to guide the extension of words to additional exemplars, and words and facts may differ with regard to extendibility. Two studies are reported in which 2–4-year-old children learned novel words and novel facts for unfamiliar objects and then were asked to extend the words and facts to additional exemplars of the training objects. In both studies, children extended the novel word to significantly more category members than they extended the novel fact. The results show that by 2 years of age, children honor the necessary extendibility of novel count nouns but are uncertain about the extendibility of arbitrary facts. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Plasma vitamins E and C concentrations of adult patients during cardiopulmonary bypass

The trajectories of change in CD4+ and CD8+ lymphocytes and serum neopterin and beta2-microglobulin (beta2M) levels were determined in 158 HIV-seropositive individuals during 5.5 years before a clinical AIDS diagnosis. Each patient was evaluated separately using a two-piece regression model with seven possible change points to identify any adverse change (inflection point) in the slopes of each immunologic marker of HIV infection. Two categories of subjects were distinguished for each marker--those with statistically significant inflection points and those who demonstrated a steady progression of changes to AIDS. Fifty-nine percent had an inflection point for CD4+ T cells. The frequency of inflection points for CD8+ was 49%, for serum neopterin -48% and for beta2M -38%. Inflection points were found over a 4-year span. Three distinctive categories of inflection points were observed on the basis of their independent occurrence: one was in CD4+ T cells, another in CD8+ T cells, and a third in the serum markers of immune activation. The inflection point for CD4+ usually occurred prior to those for CD8+ T cells (p=.0002). The HIV-positive persons with inflection points were diagnosed with AIDS when immunologic parameters were significantly more abnormal than in those with steady progression (p < .0003). Thus, these two groups differed in the course of immune changes and in the levels of immune abnormalities associated with the occurrence of clinical AIDS.     

Why children learn color and size words so differently: Evidence from adults' learning of artificial terms.

An adult simulation study examined why children's learning of color and size terms follow different developmental patterns, one in which word comprehension precedes success in nonlinguistic matching tasks versus one in which matching precedes word comprehension. In 4 experiments, adults learned artificial labels for values on novel dimensions. Training mimicked that characteristic for children learning either color words or size words. The results suggest that the learning trajectories arise from the different frames in which different dimensions are trained: Using a comparison (size-like) training regimen helps learners pick out the relevant dimension, and using a categorization (color-like) training regimen helps the learner correctly comprehend and produce dimension terms. The results indicate that the training regimen, not the meanings of the terms or the specific dimensions, determines the pattern of learning. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The relative strengths of indirect and direct word learning.

Indirect word learning lacks many of the overt social-pragmatic cues to reference available in direct word learning, yet the two result in equally robust mappings when comprehension is assessed immediately after learning. The 3 studies reported here investigated how 3-year-olds (N=96) respond to more challenging tests of the relative strengths of indirect and direct word learning. In Study 1, children's comprehension of indirectly and directly learned proper and common names was tested after a 2-day delay. Both types of learning resulted in proper name mappings that picked out an individual and in common name mappings that could be extended to another category member. In Studies 2 and 3, children's comprehension was tested after they had been provided with additional, and sometimes inconsistent, information about the scope of previously learned words. There was a hint of a difference between indirect and direct word learning, but results overall suggested that the two were equivalent. (PsycINFO Database Record (c) 2010 APA, all rights reserved)