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J S Reznick

Publications and source records attributed to J S Reznick.

At least 19 recordsLinked to original sources
PubMed1996

Measuring the vocabulary spurt: a reply to Mervis & Bertrand.

We reply to Mervis & Bertrand's report of three children (aged 1;6-1;8 at the start of the study) who evidenced a 'late' vocabulary spurt. Differences in assessing productive vocabulary, and the questionable inference that size of the lexicon is a reliable indicator of the vocabulary spurt, make it inappropriate to compare these children to previous studies that directly measure change in rate of word learning. Further work using continuous records of lexical development and controls for repeated cognitive assessments is needed to test hypotheses about the spurt and related cognitive and linguistic achievements.

Child Language↗
PubMed1996

Response modality affects human infant delayed-response performance.

Delayed response performance was assessed in 120 7-, 9-, and 11-month-old infants with correct response defined as either retrieval of a hidden object or gaze toward the location where the object was hidden. Performance improved with age, was above chance for each age group in each condition, and was more often correct with the gaze response. When direction of gaze and reach differed, direction of gaze was more likely to be correct. Infants in the reach condition were more likely to fail to reverse a previously correct response (i.e., to make the A-not-B error). Perseverative responding occurred frequently and was more likely in the reach than the gaze condition. This effect emerged primarily in the context of an incorrect response, which suggests modality-specific sensitivity to the effect of priming rather than reinforcement. Many infants showed strong side biases, and there was a tendency for more reaches to the left but gazes to the right. In a second experiment, 12 5-month-olds gazed toward the correct location more frequently than would be expected by chance but failed to reverse a previously correct response more often than older infants. These findings indicate that response modality has a significant effect on delayed-response performance.

Age Factors↗
PubMed1994

Developmental and stylistic variation in the composition of early vocabulary.

Results are reported for stylistic and developmental aspects of vocabulary composition for 1,803 children and families who participated in the tri-city norming of a new parental report instrument, the MacArthur Communicative Development Inventories. We replicate previous studies with small samples showing extensive variation in use of common nouns between age 0; 8 and 1;4 (i.e. 'referential style'), and in the proportion of vocabulary made up of closed-class words between 1;4 and 2;6 (i.e. 'analytic' vs. 'holistic' style). However, both style dimensions are confounded with developmental changes in the composition of the lexicon, including three 'waves' of reorganization: (I) an initial increase in percentage of common nouns from 0 to 100 words, followed by a proportional decrease; (2) a slow linear increase in verbs and other predicates, with the greatest gains taking place between 100 and 400 words; (3) no proportional development at all in the use of closed-class vocabulary between 0 and 400 words, followed by a sharp increase from 400 to 680 words. When developmental changes in noun use are controlled, referential-style measures do not show the association with developmental precocity reported in previous studies, although these scores are related to maternal education. By contrast, when developmental changes in grammatical function word use are controlled, high closed-class scores are associated with a slower rate of development. We suggest that younger children may have less perceptual acuity and/or shorter memory spans than older children with the same vocabulary size. As a result, the younger children may ignore unstressed function words until a later point in development while the older children tend to reproduce perceptual details that they do not yet understand. Longitudinal data show that early use of function words (under 400 words) is not related to grammatical levels after the 400-word point, confirming our 'stylistic' interpretation of early closed-class usage. We close with recommendations for the unconfounding of stylistic and developmental variance in research on individual differences in language development, and provide look-up tables that will permit other investigators to pull these aspects apart.

Child Language↗
PubMed1994

Diary vs. representative checklist assessment of productive vocabulary.

Twenty-four infants were followed longitudinally from 1.2 to 1.10. Parents maintained diaries of the child's spoken words and at two-month intervals completed a representative checklist of words produced. There was good agreement across the two instruments and robust month-to-month correlations for both. However, the overall pattern of results suggests that the diary method is more effective during the early emergence of language and the representative checklist method is more effective late in the second year when vocabulary size becomes relatively large. Accurate longitudinal assessment of vocabulary may require a combination of the diary and checklist approaches.

Female↗
PubMed1994

Variability in early communicative development.

Data from parent reports on 1,803 children--derived from a normative study of the MacArthur Communicative Development Inventories (CDIs)--are used to describe the typical course and the extent of variability in major features of communicative development between 8 and 30 months of age. The two instruments, one designed for 8-16-month-old infants, the other for 16-30-month-old toddlers, are both reliable and valid, confirming the value of parent reports that are based on contemporary behavior and a recognition format. Growth trends are described for children scoring at the 10th-, 25th-, 50th-, 75th-, and 90th-percentile levels on receptive and expressive vocabulary, actions and gestures, and a number of aspects of morphology and syntax. Extensive variability exists in the rate of lexical, gestural, and grammatical development. The wide variability across children in the time of onset and course of acquisition of these skills challenges the meaningfulness of the concept of the modal child. At the same time, moderate to high intercorrelations are found among the different skills both concurrently and predictively (across a 6-month period). Sex differences consistently favor females; however, these are very small, typically accounting for 1%-2% of the variance. The effects of SES and birth order are even smaller within this age range. The inventories offer objective criteria for defining typicality and exceptionality, and their cost effectiveness facilitates the aggregation of large data sets needed to address many issues of contemporary theoretical interest. The present data also offer unusually detailed information on the course of development of individual lexical, gestural, and grammatical items and features. Adaptations of the CDIs to other languages have opened new possibilities for cross-linguistic explorations of sequence, rate, and variability of communicative development.

Birth Order↗
PubMed1993

Genetic change and continuity from fourteen to twenty months: the MacArthur Longitudinal Twin Study.

Genetic change as well as continuity was investigated within the domains of temperament, emotion, and cognition/language for 200 pairs of twins assessed at 14 and 20 months of age in the laboratory and home. The second year of life is marked by change rather than continuity: correlations from 14 to 20 months averaged about .30 for observational measures of temperament and emotion, about .40 for language measures, and about .50 for mental development. 2 types of genetic change were examined: changes in the magnitude of genetic influence (heritability) and genetic contributions to change from 14 to 20 months. In general, heritability estimates were similar at 14 and 20 months. Evidence for genetic influence on change from 14 to 20 months emerged for several measures, implying that heritability cannot be equated with stability. Analyses of continuity indicated that genetic factors are largely responsible for continuity from 14 to 20 months.

Child Development↗
PubMed1992

Stable behavioral inhibition and its association with anxiety disorder.

"Behavioral inhibition to the unfamiliar" is a temperamental construct reflecting the tendency to be shy, timid, and constrained in novel situations. Previous work has suggested that it may be associated with anxiety disorders in children. Psychopathology was assessed in children from a nonclinical sample originally identified as behaviorally inhibited or uninhibited at 21 months and followed through 7 1/2 years. Children who remained inhibited at 4, 5 1/2 and 7 1/2 years (Stable Inhibited) had higher rates of anxiety disorders than children who were not consistently inhibited. Their parents had higher rates of multiple childhood anxiety disorders and of continuing anxiety disorder. These results suggest that the association between behavioral inhibition and anxiety disorder is accounted for by children who have stable behavioral inhibition.

Anxiety Disorders↗
PubMed1992

Temperament, emotion, and cognition at fourteen months: the MacArthur Longitudinal Twin Study.

200 pairs of twins were assessed at 14 months of age in the laboratory and home. Measures were obtained of temperament, emotion, and cognition/language. Comparisons between identical and fraternal twin correlations suggest that individual differences are due in part to heritable influences. For temperament, genetic influence was significant for behavioral observations of inhibition to the unfamiliar, tester ratings of activity, and parental ratings of temperament. For emotion, significant genetic influence was found for empathy and parental ratings of negative emotion. The estimate of heritability for parental report of expression of negative emotions was relatively high, whereas that for expression of positive emotions was low, a finding consistent with previous research. For cognition and language, genetic influence was significant for behavioral indices of spatial memory, categorization, and word comprehension. Shared rearing environment appears influential for parental reports of language and for positive emotions, but not for other measures of emotion or for temperament.

Cognition↗
PubMed1991

Further evidence of an association between behavioral inhibition and anxiety disorders: results from a family study of children from a non-clinical sample.

Behavioral inhibition to the unfamiliar, identifiable in early childhood and reflecting the tendency to exhibit withdrawal and excessive autonomic arousal to challenge or novelty, has been found to be prevalent in young offspring of parents with panic disorder and agoraphobia and associated with risk for anxiety disorders in these children. Using family study methodology, we now examine psychopathology in first degree relatives of children from a non-clinical longitudinal cohort identified at 21 months of age as inhibited (N = 22) or uninhibited (N = 19) and followed through the age of seven years for a study of preservation of temperamental characteristics in normal children. These assessments were compared with evaluations of the first degree relatives of 20 normal comparison children. Psychiatric assessments of parents (N = 110) and siblings (N = 72) were based on structured interviews conducted blindly to the temperamental classification of the index child. Parents of inhibited children, compared with parents of uninhibited and normal controls, had significantly higher risks for multiple (greater than or equal to 2) anxiety disorders, continuing anxiety disorders (both a childhood and adulthood anxiety disorder in the same parent), social phobia, and childhood avoidant and overanxious disorders. These findings provide additional support for the hypothesis linking behavioral inhibition with risk for anxiety disorder.

Adolescent↗
PubMed1990

Psychiatric correlates of behavioral inhibition in young children of parents with and without psychiatric disorders.

Behavioral inhibition is a laboratory-based temperamental category by the tendency to constrict behavior in unfamiliar situations and assumed to reflect low thresholds of limbic arousal. We previously found behavioral inhibition prevalent in the offspring of parents with panic disorder and agoraphobia. In this report, we examined the psychiatric correlates of behavioral inhibition by evaluating the sample of offspring of parents with panic disorder and agoraphobia, previously dichotomized as inhibited and not inhibited, and an existing epidemiologically derived sample of children, followed by Kagan and colleagues and originally identified at 21 months of age as inhibited or uninhibited. A third group of healthy children was added for comparison. Our findings indicate that inhibited children had increased risk for multiple anxiety, overanxious, and phobic disorders. It is suggested that behavioral inhibition may be associated with risk for anxiety disorders in children.

Agoraphobia↗
PubMed1990

Early lexical acquisition: rate, content, and the vocabulary spurt.

The transition from slow to rapid word-learning was examined in a longitudinal study of 18 children. Beginning at age 1.2, mothers kept a diary of children's words. Diary entries were discussed during phone calls to the home every 2 1/2 weeks. A chronological record of nouns and other word classes was coded from the diary records. Thirteen children evidenced a prolonged period of up to three months during which rate of acquisition markedly increased. Almost three-quarters of the words learned during this period were nouns. Five children evidenced more gradual word-learning, and acquired a balance of nouns and other word classes. These results suggest that the terms 'vocabulary spurt' and 'naming explosion' best describe children who focus their early linguistic efforts on a single strategy: learning names for things. Other children may attempt to encode a broad range of experience with a more varied lexicon, a strategy that results in more gradual lexical growth.

Female↗
PubMed1989

Direction of gaze and emergence of speech in the second year.

Orienting to the right member of a pair of identical pictures increased monotonically with age in a longitudinal sample of 14 infants seen monthly from 13 to 22 months. The magnitude of the correlation between this orientation bias and a measure of language development also rose with age reaching a peak at 20 months and then declining. It was suggested that the acceleration of vocabulary and maturational changes in the central nervous system that occur between 16 and 22 months are associated with a special excitatory state in the temporal cortex of the left hemisphere.

Dominance, Cerebral↗
PubMed1989

The validity of a parent report instrument of child language at twenty months.

When carefully assessed and analysed, parent report can provide a valuable overall evaluation of children's language at 20 months. Norming information and validity coefficients are presented here for a vocabulary checklist assessment included in the Early Language Inventory. Normative data are provided for fullterm, preterm, and precocious samples, including selected vocabulatory subsets that are indicative of early language learning style. The vocabulary checklist has substantial validity as indexed by correlations with the Bayley Scales of Infant Development and particularly with a language subscale derived from that test.

Child Language↗
PubMed1989

A multiple form word production checklist for assessing early language.

We describe the development of a set of five equivalent checklists to assess word production of children in their second year. The words on each list do not overlap, but represent comparable levels of difficulty. Thus, individual lists may be used to estimate the child's production vocabulary, and the set of lists may be used serially in a longitudinal design. A validation study on 25 infants suggests that the five lists produce comparable mean production scores, reflect differences in age, and preserve individual differences in total production and production of linguistic categories such as nouns, verbs, open class items, and closed class items. This finding provides further support for the reliability of parental report instruments in this developmental domain.

Child, Preschool↗
PubMed1989

Inhibited and uninhibited types of children.

An initial group of 100 children who were not selected a priori on any behavioral features were observed in laboratory settings at 14, 20, 32, and 48 months and their behaviors coded for inhibition and lack of inhibition to the unfamiliar. The children who had been extremely inhibited or uninhibited at both 14 and 20 months differed significantly at 4 years of age in behavior and cardiac acceleration to cognitive stress. However, for the entire sample, there was no significant relation between degree of inhibited behavior at 14 or 20 months, on the one hand, and inhibition at 4 years of age, on the other, nor any relation between behavior and heart rate acceleration. These results suggest that the constructs inhibited and uninhibited to the unfamiliar refer to children who fall at the extremes of a phenotypic continuum from shyness and restraint to sociability and affective spontaneity.

Cognition↗
PubMed1988

Biological bases of childhood shyness.

The initial behavioral reaction to unfamiliar events is a distinctive source of intraspecific variation in humans and other animals. Two longitudinal studies of 2-year-old children who were extreme in the display of either behavioral restraint or spontaneity in unfamiliar contexts revealed that by 7 years of age a majority of the restrained group were quiet and socially avoidant with unfamiliar children and adults whereas a majority of the more spontaneous children were talkative and interactive. The group differences in peripheral physiological reactions suggest that inherited variation in the threshold of arousal in selected limbic sites may contribute to shyness in childhood and even extreme degrees of social avoidance in adults.

Age Factors↗
PubMed1988

Behavioral inhibition in children of parents with panic disorder and agoraphobia. A controlled study.

To investigate the role of "behavioral inhibition to the unfamiliar" as an early temperamental characteristic of children at risk for adult panic disorder and agoraphobia (PDAG), we compared children of parents with PDAG with those from psychiatric comparison groups. Fifty-six children aged 2 to 7 years, matched for age, socioeconomic status, ethnic background, and ordinal position, were blindly evaluated at the Harvard Infant Study laboratory, Cambridge, Mass. The rates of behavioral inhibition in children of probands with PDAG, with or without comorbid major depressive disorder (MDD), were significantly higher than for our comparison group without PDAG. Further, the data suggest a progression of increasing rates of inhibition from the comparison group without MDD (15.4%), to MDD (50.0%), and to comorbid PDAG and MDD (70%) and PDAG (84.6%). In contrast, the rate of behavioral inhibition in children of probands with MDD did not meaningfully differ from the comparison group without MDD. Behavioral inhibition to the unfamiliar, as defined and measured in the previous work of the Harvard Infant Study program, is highly prevalent in the offspring of adults in treatment for PDAG. These children appear to be at risk for distress and disability in childhood and also perhaps for development of psychiatric disorder in later childhood and aulthood.

Adolescent↗