Age constraints on first versus second language acquisition: evidence for linguistic plasticity and epigenesis

Does age constrain the outcome of all language acquisition equally regardless of whether the language is a first or second one? To test this hypothesis, the English grammatical abilities of deaf and hearing adults who either did or did not have linguistic experience (spoken or signed) during early childhood were investigated with two tasks, timed grammatical judgement and untimed sentence to picture matching. Findings showed that adults who acquired a language in early life performed at near-native levels on a second language regardless of whether they were hearing or deaf or whether the early language was spoken or signed. By contrast, deaf adults who experienced little or no accessible language in early life performed poorly. These results indicate that the onset of language acquisition in early human development dramatically alters the capacity to learn language throughout life, independent of the sensory-motor form of the early experience.     

Listening comprehension and working memory are impaired in attention-deficit hyperactivity disorder irrespective of language impairment

This study investigated listening comprehension and working memory abilities in children with attention-deficit hyperactivity disorder (ADHD), presenting with and without language impairments (LI). A 4-group design classified a community sample (n = 77) of boys aged 9–12 into ADHD, ADHD + LI, LI, and Normal groups. Children completed tests of basic language and cognitive skills, verbal and spatial working memory, and passage-level listening comprehension. Multivariate analyses and post hoc comparisons indicated that ADHD children who did not have co-occurring LI comprehended factual information from spoken passages as well as normal children, but were poorer at comprehending inferences and monitoring comprehension of instructions. ADHD children did not differ from normal children in verbal span, but showed significantly poorer verbal working memory, spatial span, and spatial working memory. The ADHD + LI and LI groups were most impaired in listening comprehension and working memory performance, but did not differ from each other. Listening comprehension skills were significantly correlated with both verbal and spatial working memory, and parent–teacher ratings of inattention and hyperactivity/impulsivity. Findings that children with ADHD but no LI showed subtle higher-level listening comprehension deficits have implications for both current diagnostic practices and conceptualizations of ADHD.     

Second-order schedules of token reinforcement with pigeons: effects of fixed- and variable-ratio exchange schedules

Pigeons' key pecks produced food under second-order schedules of token reinforcement, with light-emitting diodes serving as token reinforcers. In Experiment 1, tokens were earned according to a fixed-ratio 50 schedule and were exchanged for food according to either fixed-ratio or variable-ratio exchange schedules, with schedule type varied across conditions. In Experiment 2, schedule type was varied within sessions using a multiple schedule. In one component, tokens were earned according to a fixed-ratio 50 schedule and exchanged according to a variable-ratio schedule. In the other component, tokens were earned according to a variable-ratio 50 schedule and exchanged according to a fixed-ratio schedule. In both experiments, the number of responses per exchange was varied parametrically across conditions, ranging from 50 to 400 responses. Response rates decreased systematically with increases in the fixed-ratio exchange schedules, but were much less affected by changes in the variable-ratio exchange schedules. Response rates were consistently higher under variable-ratio exchange schedules than tinder comparable fixed-ratio exchange schedules, especially at higher exchange ratios. These response-rate differences were due both to greater pre-ratio pausing and to lower local rates tinder the fixed-ratio exchange schedules. Local response rates increased with proximity to food under the higher fixed-ratio exchange schedules, indicative of discriminative control by the tokens.     

The acquisition of complex predicates in japanese specifically language-impaired and normally developing children

Japanese exhibits two different types of morphological processes. Some morphologically complex predicates are generated within the domain of the lexicon, whereas others are generated outside the domain of the lexicon. An elicited production task involving both types of complex predicates was administered to six Japanese children with specific language impairment (JSLI) and six children with normal language development (JNLD). The JSLI children experienced significant difficulty forming the lexicon-external complex predicates but much less difficulty with the lexicon-internal complex predicates while the performance of the JNLD children exhibited no such asymmetry. These preliminary results suggest that the deficit of SLI affects the ability to construct implicit procedural rules for morphology that are generated outside the lexicon while their lexical operations for morphology that are generated within the domain of the lexicon remain relatively unimpaired.     

The early acquisition of verb meaning in German by normally developing and language impaired children

The research reported here focuses on the early acquisition of event structure in German. Based on longitudinal studies from 5 normally developing (ND) and 6 language-impaired (LI) children, a model of "event structural bootstrapping" is presented that spells out how ND children log into the verb lexicon. They project a target-consistent event tree, depicting the head-of-event of transitions. Young LI children, failing to employ this bootstrapping strategy, resort to radically underspecified event representations. The results from a truth-value judgment experiment with 16 ND and 16 LI children showed that ND children perform correctly on transitional verbs, while LI children perform at chance level on the same tasks. These findings are accounted for by the model of event structural bootstrapping to the extent that LI children lack an explicit representation of the head-of-event.     

LF-interpretability and language development: a study of verbal and nominal features in Greek normally developing and SLI children

This paper includes (i) a comparison of the developmental pattern of certain morphosyntactic features in normally developing (ND) Greek children with similar data from a group of children with specific language impairment and (ii) a new analysis of the differences found. The analysis is based on a minimalist notion of LF interpretability. Depending on the feature-specification of lexical items (i.e., [+/- interpretable] at LF), a different route of development follows. In addition, phonological salience of both interpretable and noninterpretable features is argued to play an important role in an account of crosslinguistic differences in both normal and exceptional development.     

Hemispheric asymmetry in lexical decisions: the effects of grammatical class and imageability

It has been suggested that neural systems for lexical processing of nouns and verbs are anatomically distinct. The aim of the present study was to investigate if brain asymmetry for the processing of these two grammatical classes is also different. Neurologically intact adults performed a lateralized lexical decision task with grammatically unambiguous words of high, medium, and low degrees of imagery. For error scores a right visual field (RVF) advantage and an overall effect of imageability were obtained. For latency scores grammatical class and imageability modified visual field differences: in the noun class a RVF advantage was obtained only for low imagery nouns, while for the verbs the RVF advantage was present for both medium and low imagery verbs. These results suggest that the participation of right hemisphere neural systems in the processing of verbs is more limited than in the processing of nouns.     

Thermodynamics: What One Needs to Know

Thermodynamics is the foundation of many of the topics of interest in the religion-science dialogue. Here a nonmathematical outline of the principles of thermodynamics is presented, providing a historical and conceptually understandable development that can serve teachers from disciplines other than physics. The contributions of Gibbs to both classical and rational thermodynamics, emphasizing the importance of the ensemble in statistical mechanics, are discussed. The seminal ideas of Boltzmann on statistical mechanics are contrasted to those of Gibbs in a discussion of the microscopic interpretation of the second law. The role of information theory is discussed, and the modern ideas of Prigogine and nonequilibrium are outlined in some detail with further reference to the second law. Implications for our interaction with God are considered.     

Extension of Luria's Psycholinguistic Studies in Poland

One of Luria's basic interests was the organization of human cognitive processes, and thinking in particular. He believed that language and thought are closely related, and hence the manner in which we speak reflects the way we think. To verify this assumption, he and his collaborators performed a number of interesting psycholinguistic experiments with subjects of various ages and cultural backgrounds. The tasks used made the evaluation of both receptive and expressive language possible. The Narrative Ability Test described here stems from Luria's observations to a considerable degree. The test was administered to preschool children (N = 106), schoolchildren (N = 143), adolescents (N = 89), adults (N = 126), and older persons (N = 175). Findings of the 20-year studies with normal and deviant populations indicate close relationships among thought, language, and self-control. It was found that difficulty in developing narratives corresponds with a disability to process complex information. Correlations between narrative skills and age, sex, and social background were also noted.     

The development and predictive relations of play and language across the second year.

The play and language development of 171 toddlers was examined at 14 and 18 months by observing their activities on the Symbolic Play Test and by assessing their language skills using the MacArthur Communicative Development Inventories (MCDI) and the Reynell Developmental Language Scales. Additionally, data from the Bayley Scales of Infant Development and the MCDI were obtained at 24 months, in order to investigate how play and language measures taken at 14 and 18 months predict children's development at the age of 2 years. The results showed that the vocabulary production and symbolic play of the 14-month-old toddlers made a unique contribution to their language and cognitive skills at the age of 2 years, while at 18 months only language variables made a similar contribution. Other-directed pretense discriminated between the children's subsequent language and cognitive skills best, whereas nonsymbolic play had no independent predictive contribution. Significant gender differences were found in the use of nonsymbolic and symbolic play acts already at 14 months. Gender did not, however, contribute to the prediction of the children's subsequent skills, whereas maternal education significantly added to the prediction of the 2-year-olds' maximum sentence length and that of their cognitive development.