Failure to replicate a QTL association between a DNA marker identified by EST00083 and IQ

In a paper published in this journal, a possible QTL association was reported between general cognitive ability and a marker, identified by an expressed sequence tag, EST00083 (Skuder et al., 1995). In two small samples, the frequency of the common allele of this DNA marker, which was shown to be in the threonine transfer RNA gene in mitochondrial DNA, was significantly greater in a high-IQ group than in a low-IQ group. As part of the ongoing IQ QTL Project (Plomin et al., 1995), we have attempted to replicate this QTL association. First, we found that the QTL association remained significant when we compared 51 high- and 51 -average IQ subjects, drawn in part from the samples used in the previous report. However, when we examined the association in new samples of 40 extremely high-IQ subjects and 50 average-IQ subjects, the association did not replicate. This underlies the need for replication in case-control studies of allelic association.     

Individual differences in episodic memory abilities predict successful prospective memory output monitoring

Output monitoring refers to memory for one’s previously completed actions. In the context of prospective memory (PM) (e.g., remembering to take medication), failures of output monitoring can result in repetitions and omissions of planned actions (e.g., over- or under-medication). To be successful in output monitoring paradigms, participants must flexibly control attention to detect PM cues as well as engage controlled retrieval of previous actions whenever a particular cue is encountered. The current study examined individual differences in output monitoring abilities in a group of younger adults differing in attention control (AC) and episodic memory (EM) abilities. The results showed that AC ability uniquely predicted successful cue detection on the first presentation, whereas EM ability uniquely predicted successful output monitoring on the second presentation. The current study highlights the importance of examining external correlates of PM abilities and contributes to the growing body of research on individual differences in PM.     

On the adaptive function of children's and adults’ false memories

Recent research has shown that memory illusions can successfully prime both children's and adults' performance on complex, insight-based problems (compound remote associates tasks or CRATs). The current research aimed to clarify the locus of these priming effects. Like before, Deese–Roediger–McDermott (DRM) lists were selected to prime subsequent CRATs such that the critical lures were also the solution words to a subset of the CRATs participants attempted to solve. Unique to the present research, recognition memory tests were used and participants were either primed during the list study phase, during the memory test phase, or both. Across two experiments, primed problems were solved more frequently and significantly faster than unprimed problems. Moreover, when participants were primed during the list study phase, subsequent solution times and rates were considerably superior to those produced by those participants who were simply primed at test. Together, these are the first results to show that false-memory priming during encoding facilitates problem-solving in both children and adults.     

A Comparison of Single-Step and Multiple-Step Transition Analyses of Multiattribute Decision Strategies

Evaluating information is a fundamental component of multiattribute decision making that can be guided by one of many cognitive strategies. Considerable research has examined the factors that influence strategy selection; however, the identification of strategies remains problematic. The search sequence or transitions that a decision maker uses when searching a matrix of decision information can provide important clues to the strategy guiding the processing of decision information. The most common form of strategy analysis is to examine each transition from one piece of information to the next to establish whether these transitions are primarily alternative or attribute based. However, the resulting single-step transition indices often restrict strategy identification to a quantitative measure of compensatoriness and were found to provide conflicting results for the same search data. The current paper proposes a multiple-step transition analysis that records more complex, longer transitions to provide a multivariate profile of the strategy. Empirical support for the advantages of a multiple-step transition analysis over single-step transition indices is also provided.     

Relationships between psychological stress, coping and disordered eating: A review

Abstract Objective: Psychological stress and inadequate coping skills have been hypothesized to play important roles in the etiology of disordered eating. This paper reviews the empirical evidence which has emerged regarding the proposed relationships among stress. coping skills and various forms of disordered eating. Method: A search of psychological and medical databases was conducted to identify studies examining life events, and other types of psychological stress and coping strategies, in relation to the onset of disordered eating. Results: Despite methodological limitations such as the use of non-representative samples and retrospective methodologies, evidence of relationships between stress. coping and disordered eating was obtained in the majority of studies reviewed. Discussion: The implications of these findings am discussed and suggestions for future research, including the utilization of longitudinal. prospective studies, am presented.     

Sensation seeking and selective attention: focused and divided attention on a dichotic listening task.

Differences in selective attention as a function of sensation seeking, extraversion, neuroticism, and psychoticism were examined in 108 undergraduates using a dichotic listening task. Dependent measures included shadowing performance, reaction times to a secondary light task, target detection, and recall. The results suggested that high sensation seekers have better focused attention than low sensation seekers, and these effects were strongest on the 1st trials of the shadowing tasks. High sensation seekers did not attend differently than low sensation seekers to words related to their interests (sexual, violent, or drug related). Extraversion was associated with greater recall of these kinds of words, although there were no overall differences in selective attention as a function of Eysenck's dimensions. The role of arousal in personality and attention is discussed, particularly in regard to the response of sensation seekers to task novelty.