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D F Bjorklund

Publications and source records attributed to D F Bjorklund.

17 recordsLinked to original sources
PubMed2000

Deferred imitation of object-related actions in human-reared juvenile chimpanzees and orangutans.

Deferred imitation of object-related actions (e.g., picking up a cloth with a set of tongs) was assessed in 3 enculturated juvenile orangutans (Pongo pygmaeus) and 3 enculturated juvenile chimpanzees (Pan troglodytes). For each task, animals were given 4 min to explore the objects (baseline), followed by a demonstration of the target behavior, and 10 min later, were re-presented the objects (deferred phase). Each animal displayed deferred imitation on at least one trial, with each species demonstrating deferred imitation on approximately half of all possible trials. The findings were interpreted as reflecting cognitive abilities in juvenile great apes that permit deferred imitation under humanlike rearing conditions.

Age Factors↗
PubMed2000

A two-year longitudinal study of deferred imitation of object manipulation in a juvenile chimpanzee (Pan troglodytes) and orangutan (Pongo pygmaeus).

Changes in deferred imitation of novel actions on objects were assessed over a 2-year period in two enculturated, juvenile great apes (one chimpanzee, Pan troglodytes, and one orangutan, Pongo pygmaeus). Both apes displayed deferred imitation, and both displayed improve ments in deferred imitation over the 2-year period, although the magnitude of improvement was greater for the chimpanzee. This is, to our knowledge, the first experimental demonstration of longitudinal improvements of deferred imitation in great apes. The results were interpreted as reflecting maturationally paced cognitive differences consistent with other cognitive accomplishments in these species, and as demonstrating the influence that a species-atypical rearing environment can have on cognitive abilities in juvenile great apes.

Aging↗
PubMed1998

Temporal organization in children's strategy formation.

It is well established that children use study behaviors such as card sorting, category naming, and item-by-item rehearsal to assist subsequent word recall. In this article, we provide evidence that these behaviors are organized into coherent temporal patterns. Fourier analyses of individual behaviors over a sequence of five consecutive study/recall trials indicated that sorting was synchronized with the start of each trial, whereas rehearsal tended to occur later in each trial. Fourier analyses of pairs of behaviors indicated that sorting and category naming, both concerned with categorization of the to-be-remembered words, co-occurred early in each trial at a greater rate than expected based on their individual frequencies of occurrence (i.e., they were used cooperatively). In contrast, verbal rehearsal of individual words co-occurred with both sorting and category naming at a lesser rate than would be expected based on their individual frequencies of occurrence. The results thus point to a global strategy in which children learn the items' categories before they learn them individually. There was little apparent qualitative difference in temporal organization for second- and fourth-grade children. However, sorting early in each trial was more pronounced for children with better word recall (regardless of grade), and the suppressed co-occurrence of rehearsal with sorting and category naming (i.e., keeping category learning temporally separate from item learning) was more pronounced for the fourth-grade children.

Child↗
PubMed1998

Contemplating fuzzy-trace theory: the gist of it.

Brainerd and Reyna (1998, this issue) have described fuzzy-trace theory as a basic-processing theory, emphasizing age differences in children's disposition to use verbatim versus gist representations. The theoretical climate of the 1980's, when fuzzy-trace theory was first formulated, is described. Fuzzy-trace theory integrated new ideas about how cognitive development was viewed into a coherent framework, which only gradually gained acceptance as critical aspects of the theory were confirmed, counterintuitive findings were predicted and demonstrated, and other researchers began applying the theory. Fuzzy-trace theory converges with other contemporary theoretical accounts in raising the general issue of the relation between two developing representational systems and is consistent with the idea that immature (a bias toward verbatim encoding) and mature (a bias toward gist encoding) have both advantages and disadvantages at different times in development. By integrating the theory with ideas from social-contextual perspectives, the theory may have a greater impact in the future for issues of social significance.

Cognition↗
PubMed1998

Physical play and cognitive development: integrating activity, cognition, and education.

We propose that humans may have evolved a special sensitivity to certain types of social information during rough-and-tumble play that facilitates social cognition. The cognitive benefits of physical play are described as providing a break from demanding intellectual tasks, and are hypothesized to be related to gender differences in spatial cognition.

Adolescent↗
PubMed1997

Age differences in, and consequences of, multiple- and variable-strategy use on a multitrial sort-recall task.

Second-, 3rd-, and 4th-grade children were given 5 sort-recall trials with different sets of categorizable items. The authors assessed multiple-strategy use on each trial and related intertrial changes in strategy use to levels of recall. Multiple-strategy use increased with age but was observed at all grades. Fourth graders who used more strategies had higher recall, with this pattern occurring only on later trials for 2nd and 3rd graders. Children of all ages showed substantial intertrial variability in using multiple strategies. Stable-strategy use (few strategy changes across trials) was related to high levels of recall, both for individual and group data, and was associated with the use of different numbers of strategies at different ages. Results were interpreted in light of new research and theory postulating that multiple- and variable-strategy use is the rule rather than the exception in development and that strategies do not always facilitate task performance (utilization deficiencies).

Age Factors↗
PubMed1997

The role of immaturity in human development.

The possibility that infants' and young children's immature behaviors and cognitions are sometimes adaptive is explored and interpreted in terms of evolutionary theory. It is argued that developmental immaturity had an adaptive role in evolution and continues to have an adaptive role in human development. The role of developmental retardation in human evolution is discussed, followed by an examination of the relation between humans' extended childhood and brain plasticity. Behavioral neoteny, as exemplified by play, is examined, as are some potentially adaptive aspects of infants' perception and cognition that limit the amount of information they can process. Aspects of immature cognition during early childhood that may have some contemporaneous adaptive value are also discussed. It is proposed that viewing immaturity as sometimes adaptive to the developing child alters how children and their development are viewed.

Adaptation, Psychological↗
PubMed1997

In search of a metatheory for cognitive development (or, Piaget is dead and I don't feel so good myself).

With the waning of influence of Piaget's theory and the shortcomings of information-processing perspectives of cognitive growth, cognitive developmentalists lack a common set of broad, overarching principles and assumptions--a metatheory--to guide their research. Developmental biology is suggested as metatheory for cognitive development. Although it is important for developmentalists to understand proximal biological causes (e.g., brain development), most important for such a metatheory is an evolutionary perspective. Some basic principles of evolutionary psychology are introduced, and examples of contemporary research and theory consistent with these ideas are provided.

Child↗
PubMed1996

Parental investment theory and gender differences in the evolution of inhibition mechanisms.

Based on the tenets of parental investment theory, the authors postulate that there was greater pressure to inhibit potentially maladaptive emotional, social, and sexual responses on prehistoric women than men in some contexts, resulting in enhanced inhibitory abilities in women in some domains. They reviewed studies whose researchers examined gender differences on social, behavioral, and cognitive tasks involving inhibition and found gender differences favoring female humans most consistent for social tasks (e.g., control of emotions), somewhat less pronounced for behavioral tasks (e.g., delay of gratification), and weak and inconsistent for cognitive tasks (e.g., conceptual tempo). This pattern was interrupted as being consistent with the position that gender differences in inhibition are relatively domain specific in nature, with women demonstrating greater abilities on tasks related to reproduction and childrearing, which is consistent with parental investment theory.

Biological Evolution↗
PubMed1994

Training and extension of a memory strategy: evidence for utilization deficiencies in the acquisition of an organizational strategy in high- and low-IQ children.

143 9- and 10-year-old children were classified into high- and low-IQ groups and given 4 different sort/recall lists (baseline, training, near [immediate] extension, far [1-week] extension) to assess training and extension of an organizational memory strategy. All children received categorized items of moderate typicality for Phases 1, 3, and 4. For Phase 2, children were assigned to either a training or control group, with half of the children in each group receiving category typical items and the others category atypical items. Levels of recall, sorting, and clustering were greater in Phase 2 for high-IQ children, for the typical lists, and for trained children. Both the high- and low-IQ children trained with typical items continued to show high levels of recall on the near extension phase. No group of subjects maintained high levels of recall after 1 week, although levels of sorting and/or clustering on the extension trials remained high for all groups of subjects except the low-IQ control children. This latter pattern (elevated sorting/clustering with low levels of recall) is an indication of a utilization deficiency, a phase in strategy development when children use a strategy but gain little or no benefit in performance. The results provide evidence for IQ, training, and material effects in the demonstration of a utilization deficiency.

Child↗
PubMed1992

Expertise, aptitude, and strategic remembering.

Second- and fourth-grade children were classified according to their knowledge of soccer (experts vs. novices) and IQ (high vs. low), and given 2 sort-recall tasks. One task included items related to the game of soccer and the other included items from familiar natural language categories. Previous research has shown that expertise in a subject can compensate for low levels of performance on text comprehension tasks. Our results, the first examining the effects of both expertise and intelligence on a strategic memory task, were that soccer expert children recalled more items on the soccer list but not on the nonsoccer list than soccer novice children. However, soccer expertise did not modify a significant effect of IQ level, with high-IQ children recalling more than low-IQ children for all contrasts. Interest in soccer was found to be related to expertise but did not contribute to differences in memory performance. The results demonstrate that the knowledge base plays an important role in children's memory, but that domain knowledge cannot fully eliminate the effects of IQ on sort-recall tasks using domain-related materials. That is, although rich domain knowledge seemed to compensate for low aptitude, in that low-aptitude experts performed at the level of high-aptitude novices, its effects were not strong enough to eliminate performance differences between high- and low-aptitude soccer experts.

Aptitude↗
PubMed1978

Facilitative effects of haptic training on children's visual problem solving.

39 fourth grade children exposed to a haptic (active touch) match-to-sample task made significantly fewer posttest errors, relative to control subjects, on a visual problem-solving task. Further, this reduction in errors was comparable to that shown by children who had received specific training in reflective problem-solving. The results were discussed in terms of the possible facilitative effects exposure to a haptic task can have on children's visual problem-solving.

Child↗
PubMed1976

Are two hands better than one? assessing information acquired from one- and two-handed haptic exploration of random forms.

15 male undergraduates were presented with 10-sided random forms which they explored visually, or one-handed haptically, or two-handed haptically. Forms were exposed for various durations and subjects were required to draw each form immediately after its removal. The results indicated that 30 sec. of one-handed exploration and 20 and 30 sec. of two-handed exploration produced performance comparable to just 2 sec. of visual exploration. Two-handed exploration was significantly superior to one-handed exploration only at the 20-sec. exposure duration. These results illustrate the disparity in the information-gathering capabilities between the visual and haptic systems.

Form Perception↗
PubMedDate not supplied

Evolutionary developmental psychology.

Evolutionary developmental psychology is the study of the genetic and ecological mechanisms that govern the development of social and cognitive competencies common to all human beings and the epigenetic (gene-environment interactions) processes that adapt these competencies to local conditions. The basic assumptions and domains of this emerging field, as related to human life history and social and cognitive development, are outlined, as are implications for issues of importance in contemporary society.

Biological Evolution↗
PubMedDate not supplied

Child development and evolutionary psychology.

Evolutionary developmental psychology involves the expression of evolved, epigenetic programs, as described by the developmental systems approach, over the course of ontogeny. There have been different selection pressures on organisms at different times in ontogeny, and some characteristics of infants and children were selected in evolution to serve an adaptive function at that time in their life history rather than to prepare individuals for later adulthood. Examples of such adaptive functions of immaturity are provided from infancy, play, and cognitive development. Most evolved psychological mechanisms are proposed to be domain specific in nature and have been identified for various aspects of children's cognitive and social development, most notably for the acquisition of language and for theory of mind. Differences in the quality and quantity of parental investment affect children's development and influence their subsequent reproductive and childcare strategies. Some sex differences observed in childhood, particularly as expressed during play, are seen as antecedents and preparations for adult sex differences. Because evolved mechanisms were adaptive to ancestral environments, they are not always adaptive for contemporary people, and this mismatch of evolved mechanisms with modern environments is seen in children's maladjustment to some aspects of formal schooling. We argue that an evolutionary perspective can be valuable for developing a better understanding of human ontogeny in contemporary society and that a developmental perspective is important for a better understanding of evolutionary psychology.

Adolescent↗