Influences of information processing and disengagement in infants' looking behaviour

The present study considers the joint influences of information processing and disengagement in looking behaviour within a habituation paradigm. Six‐month‐old infants were habituated, during which their heart rate (HR) was measured. A parametric model of habituation yielded for each infant parameter estimates of their habituation performance. These parameters were interpreted as assessing information processing and disengagement. Corresponding measures were obtained from the HR data. The HR measures and habituation model parameter estimates were significantly correlated, as predicted. In addition, an attention getter, presented prior to each habituation trial, influenced indicators of information processing, but not of disengagement. Results confirmed the advantages of a modelling approach. In addition, and more importantly, findings led to the conclusion that both information processing as well as disengagement are involved in infants' looking behaviour in visual habituation. Copyright © 2009 John Wiley & Sons, Ltd.     

Memory span and general intelligence: A latent-variable approach

There are several studies showing that working memory and intelligence are strongly related. However, working memory tasks require simultaneous processing and storage, so the causes of their relationship with intelligence are currently a matter of discussion. The present study examined the simultaneous relationships among short-term memory (STM), working memory (WM), and general intelligence (g). Two hundred and eight participants performed six verbal, quantitative, and spatial STM tasks, six verbal, quantitative, and spatial WM tasks, and eight tests measuring fluid, crystallized, spatial, and quantitative intelligence. Especial care is taken to avoid misrepresenting the relations among the constructs being studied because of specific task variance. Structural equation modelling (SEM) results revealed that (a) WM and g are (almost) isomorphic constructs, (b) the isomorphism vanishes when the storage component of WM is partialed out, and (c) STM and WM (with its storage component partialed out) predict g.     

Family and work predictors of parenting role stress among two‐earner families of children with disabilities

Family resources (i.e. household income and spouse support), parenting challenges (i.e. number of children, difficulty finding reliable child care, and child characteristics), work rewards (i.e. work interest) and work demands (i.e. hours and work overload) were tested as predictors of parenting role stress among mothers and fathers in two‐earner families of five‐year old children with disabilities. The two‐level hierarchical model was adapted to assess mothers and fathers as nested within married couples. Both common and unique predictors of maternal and paternal parenting role stress were found. Having fewer children in the family predicted less stress for both parents. Household income and an interaction between child behaviour problems and work interest were significant predictors of maternal parenting role stress. In contrast, greater difficulty in finding reliable child care predicted higher levels of parenting role stress for fathers but not mothers. The policy and research implications of these findings are discussed. Copyright © 2005 John Wiley & Sons, Ltd.     

Doing cognitive neuroscience: a third way

The “top-down” and “bottom-up” approaches have been thought to exhaust the possibilities for doing cognitive neuroscience. We argue that neither approach is likely to succeed in providing a theory that enables us to understand how cognition is achieved in biological creatures like ourselves. We consider a promising third way of doing cognitive neuroscience, what might be called the “neural dynamic systems” approach, that construes cognitive neuroscience as an autonomous explanatory endeavor, aiming to characterize in its own terms the states and processes responsible for brain-based cognition. We sketch the basic motivation for the approach, describe a particular version of the approach, so-called ‘Dynamic Causal Modeling’ (DCM), and consider a concrete example of DCM. This third way, we argue, has the potential to avoid the problems that afflict the other two approaches.     

Understanding Gang Joining from a Cross Classified Multi-Level Perspective

The present study seeks to address the gap in our understanding of the role of community- and school-level factors on individual-level gang joining. We assess our research question by bringing together data from a statewide survey of more than 35,000 school youth who were enrolled in more than 250 schools and resided in more than 300 communities. We first use multilevel modeling techniques to examine the independent relationship of community and school on the likelihood of individual youth gang joining. Second, while controlling for individual-level risk and protective factors, we examine the simultaneous relationship of community- and school-level conditions on gang joining. Overall, the results of the present study suggest that both community- and school-level characteristics play a role in gang joining. The results of the cross-classified model suggests that community structural characteristics may serve as protection against gang joining. Individual-level risk and protective factors remain important for understanding gang joining. A variety of factors are related to gang joining. Though individual-level factors are important, community- and school-level factors are meaningful in the understanding of gang joining.     

Adolescents' music preferences and personality characteristics

The present paper examined the structure of Dutch adolescents' music preferences, the stability of music preferences and the relations between Big‐Five personality characteristics and (changes in) music preferences. Exploratory and confirmatory factor analyses of music‐preference data from 2334 adolescents aged 12–19 revealed four clearly interpretable music‐preference dimensions: Rock, Elite, Urban and Pop/Dance. One thousand and forty‐four randomly selected adolescents from the original sample filled out questionnaires on music preferences and personality at three follow‐up measurements. In addition to being relatively stable over 1, 2 and 3‐year intervals, music preferences were found to be consistently related to personality characteristics, generally confirming prior research in the United States. Personality characteristics were also found to predict changes in music preferences over a 3‐year interval. Copyright © 2007 John Wiley & Sons, Ltd.     

A COMPUTATIONAL THEORY OF SELECTION BY CONSEQUENCES APPLIED TO CONCURRENT SCHEDULES

Virtual organisms animated by a computational theory of selection by consequences responded on symmetrical and asymmetrical concurrent schedules of reinforcement. The theory instantiated Darwinian principles of selection, reproduction, and mutation such that a population of potential behaviors evolved under the selection pressure exerted by reinforcement from the environment. The virtual organisms' steady‐state behavior was well described by the power function matching equation, and the parameters of the equation behaved in ways that were consistent with findings from experiments with live organisms. Together with previous research on single‐alternative schedules (McDowell, 2004; McDowell & Caron, 2007) these results indicate that the equations of matching theory are emergent properties of the evolutionary dynamics of selection by consequences.     

PARENTAL TRAINING OF THE PLURAL MORPHEME IN NORMAL TODDLERS1

Experimental studies with young normal children can provide useful strategy for the functional analysis of language. Research by Whitehurst (Journal of Experimental Child Psychology, 1972, 13 , 502–515) exemplifies this approach, in which 2-yr-old children were exposed to a training procedure that involved imitation and differential reinforcement for a two-word productive sequence of the adjective-noun form. Results indicated that these young children could be trained to produce rudimentary novel utterances that were grammatically appropriate. More recently, Hursh and Sherman (Journal of Experimental Child Psychology, 1973, 15 , 328–339) reported the existence of a functional relationship between parental modelling and reinforcement of vocalizations, and increased instances of these vocalizations in young (15- to 20-month-old) children. These demonstrations relate to a summary of findings with linguistically deviant populations discussed by Sherman (Advances in Child Development, 1971). The present study attempts to extend these “generative” investigations to normal children and to provide useful information for those interested in teaching speech forms to them. Modelling and differential reinforcement were used by three mothers to establish the use of the plural morpheme in the speech of their 19- to 25-month-old children. During training trials, verbal praise was presented contingent on correct labelling of singular and plural items, while correct labelling was modelled if the child responded incorrectly. Children learned to label specifically trained sets of singular and plural items and also exhibited correct labelling when asked to label never-trained singular and plural items. After establishing correct usage, the same training procedures were used to train reversed labelling (plural responses to single items and singular responses to plural items). This produced a corresponding reversal of responding (both trained and untrained items) by each child for the plural items but not for singular items. Correct singular and plural labelling was recovered by returning to the initial procedures.