This target article considers the relation of fluid cognitive functioning to general intelligence. A neurobiological model differentiating working memory/executive function cognitive processes of the prefrontal cortex from aspects of psychometrically defined general intelligence is presented. Work examining the rise in mean intelligence-test performance between normative cohorts, the neuropsychology and neuroscience of cognitive function in typically and atypically developing human populations, and stress, brain development, and corticolimbic connectivity in human and nonhuman animal models is reviewed and found to provide evidence of (...) mechanisms through which early experience affects the development of an aspect of cognition closely related to, but distinct from, general intelligence. Particular emphasis is placed on the role of emotion in fluid cognition and on research indicating fluid cognitive deficits associated with early hippocampal pathology and with dysregulation of the hypothalamic-pituitary-adrenal axis stress-response system. Findings are seen to be consistent with the idea of an independent fluid cognitive construct and to assist with the interpretation of findings from the study of early compensatory education for children facing psychosocial adversity and from behavior genetic research on intelligence. It is concluded that ongoing development of neurobiologically grounded measures of fluid cognitive skills appropriate for young children will play a key role in understanding early mental development and the adaptive success to which it is related, particularly for young children facing social and economic disadvantage. Specifically, in the evaluation of the efficacy of compensatory education efforts such as Head Start and the readiness for school of children from diverse backgrounds, it is important to distinguish fluid cognition from psychometrically defined general intelligence. (Published Online April 5 2006) Key Words: cognition; cognition-emotion reciprocity; developmental disorders; emotion; fluid cognition; Flynn effect; general intelligence; limbic system; neuroscience; phenylketonuria; prefrontal cortex; psychometrics; schizophrenia. (shrink)

Aspects of the history of behavioural science are reviewed, pointing to its fragmented and faction-ridden nature. The emergence of evolutionary psychology (EP) is viewed in this context. With the help of a dual-layered model of behavioural control, the case is made for a more integrative perspective towards EP. The model's application to both behaviour and complex human information processing is described. Similarities in their control are noted. It is suggested that one layer of control (‘on-line’) corresponds to the encapsulated modules (...) of EP whereas the off-line controls provide the plasticity and flexibility suggested by its critics. (shrink)

This is a critical notice of Evolution's Eye by Susan Oyama, focusing on developmental systems theory primarily in relation to the nature-nurture debates and the explanation of behaviour.

Although biologists and philosophers of science generally agree that genes cannot determine the forms of biological and psychological traits, students, journalists, politicians, and other members of the general public nonetheless continue to embrace genetic determinism. This article identifies some of the concerns typically raised by individuals when they first encounter the systems perspective that biologists and philosophers of science now favor over genetic determinism, and uses arguments informed by that perspective to address those concerns. No definitive statements can yet be (...) made about why genetic determinism has proven so resilient in the face of empirical evidence pointing up its deficiencies, but conveying the essential interdependence of 'nature' and 'nurture' to the general public will likely require deployment of the arguments that systems theorists ordinarily use to reject genetic determinism. In addition, the elaboration of new metaphors that focus attention on the dynamic nature of trait construction will likely prove valuable, because re-conceptualizing notions like 'genes' and 'nature' will probably be one of the most effective ways to help students and the general public abandon the genetic determinism that biologists now recognize as indefensible. (shrink)

Parental effects are a major source of phenotypic plasticity and may influence offspring phenotype in concert with environmental demands. Studies of “environmental epigenetics” suggest that (1) DNA methylation states are variable and that both demethylation and remethylation occur in post‐mitotic cells, and (2) that remodeling of DNA methylation can occur in response to environmentally driven intracellular signaling pathways. Studies of mother‐offspring interactions in rodents suggest that parental signals influence the DNA methylation, leading to stable changes in gene expression. If parental (...) effects do indeed enhance the “match” between prevailing environmental demands and offspring phenotype, then the potential for variation in environmental conditions over time would suggest a mechanism that requires active maintenance across generations through parental signaling. We suggest that parental regulation of DNA methylation states is thus an ideal candidate mechanism for parental effects on phenotypic variation. (shrink)

More than 40 years ago, Gilbert Gottlieb and like-minded scholars argued for the philosophical necessity of approaching genetic contributions to development through a multilevel, bidirectional systems perspective. Charney's target article builds on this heritage in significant ways, offering more recent examples of the interactions of biology and context, as well as the diversity of developmental mechanisms, and reaffirming a way forward for genetic research.