In conversation with J. Philippe Rushton

The interview covers Rushton’s background in England, South Africa, and Canada, his education at the University of London (B.Sc., 1970; Ph.D., 1973), and his early research (1970–1980) on the social learning of generosity in 7- to 11-year olds. In his first book, Altruism, socialization, and society (1980), Rushton solved two “anomalies” for his social learning perspective—altruism in animals and traits in people—causing a “paradigm shift” for him toward sociobiology. He spent January to June 1981 at the University of California, Berkeley, to study the longitudinal stability of personality traits like altruism. There, he was influenced by Jensen’s work on g and race differences in rate of maturation and two-egg twinning. Subsequently, Rushton found that across 60 variables, Europeans fall between East Asians and Africans, closer to East Asians. He extrapolated Wilson’s (fast–slow) r-K life history theory to explain the pattern. Also covered is Rushton’s research on the heritability of altruism, and Genetic Similarity Theory explaining assortative mating and ethnic nepotism. Spouses and best friends are as similar as half-siblings and people randomly chosen from the same ethnic group are as related as first cousins. Altruism follows lines of similarity to replicate genes effectively. Rushton’s research on creativity is described.     

IQ and the wealth of nations: How much reverse causality?

This paper uses data from 130 IQ test administrations worldwide and employs regression analysis to try to quantify the impact of living conditions on average IQ scores in nationally-representative samples. The study emphasizes the possible role of conditions at or near the test-takers' time of birth. The paper finds that the impact of living conditions is of much smaller magnitude than is suggested by just looking at correlations between average IQ scores and socioeconomic indicators. After controlling for test-takers' region of ancestry, the impact of parasitic diseases on average IQ is found to be statistically insignificant when test results from the Caribbean are included in the analysis. As far as IQ and the wealth of nations are concerned, causality thus appears to run mostly from the former to the latter. The test-takers' region of ancestry dominates the regression results. While differences in average scores worldwide can thus be plausibly viewed as being influenced by genetic differences across world regions, it is also possible that score differences are influenced by regional differences in culture that are independent of genetic factors. Differences in average IQ across world regions may change in the years ahead insofar as the strength of Flynn effects may not be uniform, but some regional differences in average g levels seem likely to continue indefinitely.     

Socio-economic health inequalities: Their origins and implications

Abstract

Evidence attests to substantial variations in health contingent on socioeconomic position. It is argued that these effects cannot be dismissed as artefact nor can they be explained, in the main, by either social selection or an unequal distribution of accepted behavioural risk factors among different social groups. The most likely explanation would seem to be social causation. However, it is continuing social and material inequality that appears most implicated; accounts which locate the effects in childhood social and material causes are far less compelling. The persistence of socioeconomic health differentials into the materially better-off social strata and the possible determining role of relative as well as absolute living standards suggest that psychological, in addition to material, variables are likely to be involved. Isolating the key psychological variables and identifying the nature of their influences will not be easy tasks, although social relations, psychological stress, uplifts, and control have emerged as possible candidates. However, psychological mediators of this sort most probably constitute surface rather than basic causes. Socio-economic inequality, it is contended, remains the basic cause, and, as such, the proper target for intervention. Psychological interventions are unlikely to yield much in the way of dividends in this context and indeed could inadvertently contribute to victim blaming.     

When does feature search fail to protect against attentional capture?

ABSTRACT

When participants search for a shape (e.g., a circle) among a set of homogenous shapes (e.g., triangles) they are subject to distraction by colour singletons that are more salient than the target. However, when participants search for a shape among heterogeneous shapes, the presence of a non-target colour singleton does not slow responses to the target. Attempts have been made to explain these results from both bottom-up and top-down perspectives. What both accounts have in common is that they do not predict the occurrence of attentional capture on typical feature search displays. Here, we present a case where manipulating selection history, rather than the displays themselves, leads to attentional capture on feature search trials. The ability to map specific colours to the target and distractor appears to be what enables resistance to capture during feature search.     

Mediated conditioning versus retrospective revaluation in humans: The influence of physical and functional similarity of cues

Two experiments assessed whether similarity between the two elements of a compound would influence the degree of mediated extinction versus recovery from overshadowing in human causal judgements. In both Experiments 1 and 2, we assessed the influence of extinguishing one element of a two-element compound on judgements about the other element. In Experiment 1 we manipulated the physical similarity of the two elements of the compound; in Experiment 2, we used equivalence and distinctiveness pretraining in order to vary their functional similarity. We found that these procedures influenced mediated extinction and recovery from overshadowing as a function of both physical and acquired similarity and distinctiveness, respectively. The implications of these results for previously reported differences between humans and nonprimate animals are discussed.     

The word class effect in the picture–word interference paradigm

The word class effect in the picture–word interference paradigm is a highly influential finding that has provided some of the most compelling support for word class constraints on lexical selection. However, methodological concerns called for a replication of the most convincing of those effects. Experiment 1 was a direct replication of Pechmann and Zerbst (2002 Pechmann, T. and Zerbst, D. 2002. The activation of word class information during speech production. Journal of Experimental Psychology: Learning, Memory, and Cognition, 28: 233–243. [Crossref], [PubMed], [Web of Science ®] , [Google Scholar]; Experiment 4). Participants named pictures of objects in the context of noun and adverb distractors. Naming took place in bare noun and sentence frame contexts. A word class effect emerged in both bare noun and sentence frame naming conditions, suggesting a semantic origin of the effect. In Experiment 2, participants named objects in the context of noun and verb distractors whose word class relationship to the target and imageability were orthogonally manipulated. As before, naming took place in bare noun and sentence frame naming contexts. In both naming contexts, distractor imageability but not word class affected picture naming latencies. These findings confirm the sensitivity of the picture–word interference paradigm to distractor imageability and suggest the paradigm is not sensitive to distractor word class. The results undermine the use of the word class effect in the picture–word interference paradigm as supportive of word class constraints during lexical selection.     

Temporal distinctiveness and repetition benefits in task switching: Disentangling stimulus-related and response-related contributions

Despite the popularity of the Wason selection task in the psychology of reasoning, doubt remains as to whether card choices actually reflect a process of reasoning. One view is that while participants reason about the cards and their hidden sides—as indicated by protocol analysis—this reasoning merely confabulates explanations for cards that were preconsciously cued. This hypothesis has apparently been supported by studies that show that participants predominantly inspect cards which they end up selecting. In this paper, we reanalyse the data of one such study, which used eye-movement tracking to record card inspection times (Ball, Lucas, Miles, & Gale, 2003). We show that while cards favoured by matching bias are inspected for roughly equal lengths of times, their selection rates are strongly affected by their logical status. These findings strongly support a two-stage account in which attention is necessary but not sufficient for card selections. Hence, reasoning does indeed affect participants' choices on this task.     

Effects of visual cue and response assignment on spatial stimulus coding in stimulus–response compatibility

Tlauka and McKenna (2000 Tlauka, M. and McKenna, F. P. 2000. Hierarchical knowledge influences stimulus–response compatibility effects. Quarterly Journal of Experimental Psychology, 53A: 85–103.  [Google Scholar]) reported a reversal of the traditional stimulus–response compatibility (SRC) effect (faster responding to a stimulus presented on the same side than to one on the opposite side) when the stimulus appearing on one side of a display is a member of a superordinate unit that is largely on the opposite side. We investigated the effects of a visual cue that explicitly shows a superordinate unit, and of assignment of multiple stimuli within each superordinate unit to one response, on the SRC effect based on superordinate unit position. Three experiments revealed that stimulus–response assignment is critical, while the visual cue plays a minor role, in eliciting the SRC effect based on the superordinate unit position. Findings suggest bidirectional interaction between perception and action and simultaneous spatial stimulus coding according to multiple frames of reference, with contribution of each coding to the SRC effect flexibly varying with task situations.     

My word! Interference from reading object names implies a role for competition during picture name retrieval

A related word prime has been found to interfere with picture naming after unrelated intervening trials (word-to-picture interference). Recently, Stroop-type picture–word interference effects have been interpreted in terms of a postlexical response exclusion process rather than a competitive lexical selection process. An experiment is reported that examines whether word-to-picture effects could reflect response exclusion mechanisms and, more generally, strategic processing of the word prime. Forty-eight volunteer university students named aloud sequences of semantically related (and unrelated) word primes and picture targets, separated by two unrelated filler stimuli. On half of the trials, participants were asked to count backwards in threes from a random number presented immediately after naming the prime word. They were also given a surprise recall test at the end of the naming block. Results for naming times and errors indicated a main effect of relatedness; semantic interference effects were not dependent on the unfilled gap following the word prime trial and were also not tied to episodic recall of prime words. The data indicate that slowed picture naming times are more likely to emerge from processes intrinsic to word prime naming rather than controlled processing and do not readily fit the postlexical response exclusion account. The results are considered in relation to two recent accounts of interference over unrelated trials, which refer to some form of competition at, or prior to, lexical access.