Behavioral genetic (BG) research has yielded many important discoveries about the origins of human behavior, but offers little insight into how we might improve outcomes. We posit that this gap in our knowledge base stems in part from the epidemiologic nature of BG research questions. Namely, BG studies focus on understanding etiology as it currently exists, rather than etiology in environments that could exist but do not as of yet (e.g., etiology following an intervention). Put another way, they focus exclusively (...) on the etiology of “what is” rather than “what could be”. The current paper discusses various aspects of this field-wide methodological reality, and offers a way to overcome it by demonstrating how behavioral geneticists can incorporate an experimental approach into their work. We outline an ongoing study that embeds a randomized intervention within a twin design, connecting “what is” and “what could be” for the first time. We then lay out a more general framework for a new field—experimental BGs—which has the potential to advance both scientific inquiry and related philosophical discussions. (shrink)

Blair equates the constructs of working memory (WM), executive function, and general fluid intelligence (gF). We argue that there is good reason not to equate these constructs. We view WM and gF as separable but highly related, and suggest that the mechanism behind the relationship is controlled attention – an ability that is dependent on normal functioning of the prefrontal cortex. (Published Online April 5 2006).

A hallmark of intelligent behavior is rationality – the disposition and ability to think analytically to make decisions that maximize expected utility or follow the laws of probability. However, the question remains as to whether rationality and intelligence are empirically distinct, as does the question of what cognitive mechanisms underlie individual differences in rationality. In a sample of 331 participants, we assessed the relationship between rationality and intelligence. There was a common ability underpinning performance on some, but not all, rationality (...) tests. Latent factors representing rationality and general intelligence were strongly correlated (r =.54), but their correlation fell well short of unity. Rationality correlated significantly with fluid intelligence (r =.56), working memory capacity (r =.44), and attention control (r =.49). Attention control fully accounted for the relationship between working memory capacity and rationality, and partially accounted for the relationship between fluid intelligence and rationality. We conclude by speculating about factors rationality tests may tap that other cognitive ability tests miss, and outline directions for further research. (shrink)

The question of what explains individual differences in expertise within complex domains such as music, games, sports, science, and medicine is currently a major topic of interest in a diverse range of fields, including psychology, education, and sports science, to name just a few. Ericsson and colleagues’ deliberate practice view is highly influential perspective in the literature on expertise and expert performance—but is it viable as a testable scientific theory? Here, reviewing more than 25 years of Ericsson and colleagues’ writings, (...) we document critical inconsistencies in the definition of deliberate practice, along with apparent shifts in the standard for evidence concerning deliberate practice. We also consider the impact of these issues on progress in the field of expertise, focusing on the empirical testability and falsifiability of the deliberate practice view. We then discuss a multifactorial perspective on expertise, and how open science practices can accelerate progress in research guided by this perspective. (shrink)