Karl S. Rosengren

Grasping the Nature of Pictures

The role of experience in the development of pictorial competence has been the center of substantial debate. The four studies presented here help resolve the controversy by systematically documenting and examining manual exploration of depicted objects by infants. We report that 9-month-old infants manually investigate pictures, touching and feeling depicted objects as if they were real objects and even trying to pick them up off the page. The same behavior was observed in babies from two extremely different societies (the United States and the Ivory Coast). This investigation of pictures occurs even though infants can discriminate between real objects and their depictions. By the time infants are 19 months of age, their manual exploration is replaced by pointing at depicted objects. These results indicate that initial uncertainty about the nature of pictures leads infants to investigate them. Through experience, infants begin to acquire a concept of “picture.” This concept includes the fact that a picture has a dual nature (it is both an object and a representation of something other than itself), as well as knowledge about the culturally appropriate use of pictures.

BEYOND LABELING: THE ROLE OF MATERNAL INPUT IN THE ACQUISITION OF RICHLY STRUCTURED CATEGORIES

Recent research shows that preschool children are skilled classifiers, using categories both to organize information efficiently and to extend knowledge beyond what is already known. Moreover, by 2 1/2 years of age, children are sensitive to nonobvious properties of categories and assume that category members share underlying similarities. Why do children expect categories to have this rich structure, and how do children appropriately limit this expectation to certain domains (i.e., animals vs. artifacts)? The present studies explore the role of maternal input, providing one of the first detailed looks at how mothers convey information about category structure during naturalistic interactions. Forty-six mothers and their 20- or 35-month-old children read picture books together. Sessions were videotaped, and the resulting transcripts were coded for explicit and implicit discussion of animal and artifact categories. Sequences of gestures toward pictures were also examined in order to reveal the focus of attention and implicit links. drawn between items. Results indicate that mothers provided a rich array of information beyond simple labeling routines. Taxonomic categories were stressed in subtle and indirect ways, in both speech and gesture, especially for animals. Statements and gestures that linked two pictures were more frequent for taxonomically related animal pictures than for other picture pairs. Mothers also generalized category information using generic noun phrases, again more for animals than for artifacts. However, mothers provided little explicit discussion of nonobvious similarities, underlying properties, or inductive potential among category members. These data suggest possible mechanisms by which a notion of kind is conveyed in the absence of detailed information about category essences.

Imagining the impossible : magical, scientific, and religious thinking in children

Preface 1. The makings of the magical mind: the nature of function of sympathetic magical thinking Carol Nemeroff and Paul Rozin 2. Phenomenalistic perception and rational understanding in the mind of an individual: a fight for dominance Eugene Subbotsky 3. Metamorphosis and magic: the development of childrens thinking about possible events and plausible mechanisms Karl S. Rosengren and Anne K. Hickling 4. The development of beliefs about metaphysical causality in imagination, magic and religion Jacqui Woolley 5. Intuitive ontology and cultural input in the acquisition of religious concepts Pascal Boyer and Sheila Walker 6. On not falling down to earth: childrens metaphysical questions Paul L. Harris 7. Putting different things together: the development of metaphysical thinking Carl N. Johnson 8. Versions of personal story telling: versions of experience: genres as tools for creating alternate realities Peggy J. Miller, Julia Hengst, Kristin Alexander and Linda L. Sperry 9. The influence of culture on fantasy play: the case of Mennonite children Marjorie Taylor and Stephanie M. Carlson 10. Religion, culture, and beliefs about reality in moral reasoning Elliot Turiel and Kristin Neff 11. Beyond scopes: why creationism is here to stay E. Margaret Evans 12. Knowledge change in response to date in science, religion, and magic Clark A. Chinn and William F. Brewer 13. Theology and physical science: a story of developmental influence at the boundaries David E. Schrader.

Emotion and motivated behavior: postural adjustments to affective picture viewing.

Thirty-six participants (18 female, 18 male) viewed affective pictures to investigate the coupling between emotional reactions and motivated behavior. Framed within the biphasic theory of emotion, the three systems approach was employed by collecting measures of subjective report, expressive physiology, and motivated behavior. Postural adjustments associated with viewing affective pictures were measured. Results indicated sex-differences for postural responses to unpleasant pictures; an effect not found for pleasant and neutral picture contents. Females exhibited increased postural movement in the posterior direction, and males exhibited increased movement in the anterior direction, for unpleasant pictures. Subjective report of valence and arousal using the self-assessment manikin (SAM), and the startle eye-blink reflex were collected during a separate session, which replicated previous picture-viewing research. Specifically, participants rated pleasant pictures higher in valence and exhibited smaller startle responses compared to unpleasant pictures. Females also reported lower valence ratings compared to males across all picture contents. These findings extend our knowledge of motivated engagement with affective stimuli and indicate that postural responses may provide insight into sex-related differences in withdrawal behavior.

The coexistence of natural and supernatural explanations across cultures and development.

Although often conceptualized in contradictory terms, the common assumption that natural and supernatural explanations are incompatible is psychologically inaccurate. Instead, there is considerable evidence that the same individuals use both natural and supernatural explanations to interpret the very same events and that there are multiple ways in which both kinds of explanations coexist in individual minds. Converging developmental research from diverse cultural contexts in 3 areas of biological thought (i.e., the origin of species, illness, and death) is reviewed to support this claim. Contrary to traditional accounts of cognitive development, new evidence indicates that supernatural explanations often increase rather than decrease with age and supports the proposal that reasoning about supernatural phenomena is an integral and enduring aspect of human cognition.

The Credible Shrinking Room: Very Young Children's Performance With Symbolic and Nonsymbolic Relations

Becoming a proficient symbol user is a universal developmental task in the first years of life, but detecting and mentally representing symbolic relations can be quite challenging for young children To test the extent to which symbolic reasoning per se is problematic, we compared the performance of 2 1/2-year-olds in symbolic and nonsymbolic versions of a search task. The children had to use their knowledge of the location of a toy hidden in a room to draw an inference about where to find a miniature toy in a scale model of the room (and vice versa) Children in the nonsymbolic condition believed a shrinking machine had caused the room to become the model They were much more successful than children in the symbolic condition, for whom the model served as a symbol of the room The results provide strong support for the role of dual representation in symbol understanding and use.

Gait adjustments in older adults: activity and efficacy influences.

Factors that influence gait adjustments in active and sedentary older adults were examined in this study. Fifty-five older adults (60-85 years) completed a series of physical activity and self-efficacy measures (gait, falls) and the Berg Balance Scale (K. O. Berg, S. L. Wood-Dauphinee, J. I. Williams, & B. Maki, 1992). Participants then completed a series of walking trials that included walking with and without obstacles placed in their path. Sedentary older adults adopted a more cautious walking style than active ones, exhibiting shorter step lengths and slower step velocities. Age, physical activity level, balance, and the efficacy measures were all found to be significantly correlated with gait speed. Hierarchical regression analyses indicated that once age, sex, and body mass index were controlled for, gait efficacy had a significant independent effect on gait speed. These results highlight the importance of examining multiple factors when examining the control of gait.

Muscle Quality, Aerobic Fitness and Fat Mass Predict Lower-Extremity Physical Function in Community-Dwelling Older Adults

Background: Muscle mass, strength and fitness play a role in lower-extremity physical function (LEPF) in older adults; however, the relationships remain inadequately characterized. Objective: This study aimed to examine the relationships between leg mineral free lean mass (MFLMLEG), leg muscle quality (leg strength normalized for MFLMLEG), adiposity, aerobic fitness and LEPF in community-dwelling healthy elderly subjects. Methods: Fifty-five older adults (69.3 ± 5.5 years, 36 females, 19 males) were assessed for leg strength using an isokinetic dynamometer, body composition by dual energy X-ray absorptiometry and aerobic fitness via a treadmill maximal oxygen consumption test. LEPF was assessed using computerized dynamic posturography and stair ascent/descent, a timed up-and-go task and a 7-meter walk with and without an obstacle. Results: Muscle strength, muscle quality and aerobic fitness were similarly correlated with static LEPF tests (r range 0.27–0.40, p < 0.05); however, the strength of the independent predictors was not robust with explained variance ranging from 9 to 16%. Muscle quality was the strongest correlate of all dynamic LEPF tests (r range 0.54–0.65, p < 0.001). Using stepwise linear regression analysis, muscle quality was the strongest independent predictor of dynamic physical function explaining 29–42% of the variance (p < 0.001), whereas aerobic fitness or body fat mass explained 5–6% of the variance (p < 0.05) depending on performance measure. Conclusions: Muscle quality is the most important predictor, and aerobic fitness and fat mass are secondary predictors of LEPF in community-dwelling older adults. These findings support the importance of exercise, especially strength training, for optimal body composition, and maintenance of strength and physical function in older adults.

Effects of Change in Physical Activity on Physical Function Limitations in Older Women: Mediating Roles of Physical Function Performance and Self-Efficacy

OBJECTIVES: To examine the hypothesis that changes in self‐efficacy and functional performance mediate, in part, the beneficial effect of physical activity on functional limitations over time.

A new approach to detecting asymmetries in gait

BACKGROUND Traditional parameters used to assess gait asymmetries, e.g., joint range of motion or symmetry indices, fail to provide insight regarding timing and magnitude of movement deviations among lower limb joints during the gait cycle. This study evaluated the efficacy of a new approach for quantifying aspects of gait asymmetry. METHODS Asymmetric gait was simulated by joint bracing. The dominant leg knee or ankle was constrained in ten healthy young adult males. Kinematic data were collected during three-minute trials for treadmill-walking conditions: unbraced, knee-braced, and ankle-braced. We created a regions of deviation analysis, which compared asymmetric walking (flexion/extension behavior) relative to normative (group-averaged unbraced) data. Symmetry/asymmetry between bilateral joint pairs was quantified and the behavior of specific joints relative to normative data was assessed using this analysis. FINDINGS While traditional measures (e.g., maximum range of motion) grossly detected asymmetries due to bracing, these new analyses identified significant regions of asymmetry. Knee-bracing affected the knee during mid-swing, but also increased ankle asymmetry during both terminal stance and mid-swing and hip asymmetry during mid-stance and mid-swing. Ankle-bracing created asymmetries at the ankle (terminal stance and initial swing) and hip (terminal stance), but none at the knee. INTERPRETATION Region of deviation analysis effectively identified the timing and magnitude of deviations throughout the gait cycle, and provided information about the impact of a joint-mobility perturbation on neighboring joints. This new methodology will be useful in clinical settings to identify, characterize, and monitor recovery from asymmetric behaviors associated with injuries or pathologies.