Is the interference between memory processing and timing specific to the use of verbal material?

Increasing load in a memory task performed simultaneously with a timing task shortens perceived time, an effect that has been observed previously with memory tasks using verbal material. The present experiments examine whether two similar memory tasks, one in which verbal material is used and another one in which nonverbal material is used, would produce similar interference effects on concurrent time reproduction. In Experiment 1, the number of nonverbal stimuli (pseudo-random dot patterns) was manipulated in a memory task performed while a temporal interval to be reproduced was encoded. Reproductions shortened proportionally to the duration of memory processing executed during time estimation. Verbal stimuli (consonants) were used in Experiment 2 in otherwise identical experimental conditions. Effects observed in Experiment 2 were comparable to those obtained in Experiment 1. Taken together, these results support the notion that interference from memory tasks on concurrent time estimation is not determined by the specific type of material processed in memory, but instead by the duration of memory processing.     

Fill-in and infill errors in order memory

Many current models of memory are specified with enough detail to make predictions about patterns of errors in memory tasks. However, there are often not enough empirical data available to test these predictions. We report two experiments that examine the relative frequency of fill-in and infill errors. In immediate serial recall tasks, subjects sometimes incorrectly recall item N too soon, placing it in position N-1. The error of interest is which item is recalled after this initial mistake. A fill-in error is the tendency to recall item N-1 next, whereas an infill error is the tendency to recall item N+1 next. Both experiments reveal more fill-in than infill errors, not only overall but at each possible error location throughout the list. The overall ratio is approximately 2:1. We conclude that none of the currently existing models adequately accounts for fill-in and infill errors.     

Domain-specificity and theory of mind: evaluating neuropsychological evidence

Humans' unique aptitude for reasoning about mental states, known as Theory of Mind (ToM), can help explain the unique character of human communication and social interaction. ToM has been studied extensively in children, but there is no clear account of the cognitive basis of ToM in adults. Evidence from functional imaging and neuropsychology is beginning to address this surprising gap in our understanding, and this evidence is often thought to favour a domain-specific or modular architecture for ToM. We present a systematic approach to this issue for the paradigmatic case of belief reasoning, and argue that neuropsychological data provide no clear evidence for domain-specificity or modularity. Progress in understanding ToM requires new tasks that isolate potentially distinct components of this complex ability.     

The multi-item localization (MILO) task: measuring the spatiotemporal context of vision for action

We describe a new multi-item localization task that can be used to probe the temporal and spatial contexts of search-like behaviors. A sequence of four target letters (e.g., E, F, G, and H) was presented among four distractor letters. Observers located the targets in order. Both retrospective and prospective components of performance were examined. The retrospective component was assessed by having target items either vanish or remain once they had been located. This manipulation had little effect on search performance, suggesting that old target items can be efficiently ignored. The prospective component was assessed by shuffling future target and distractor locations after each response. This manipulation revealed that observers typically plan ahead at least one target into the future. However, even when observers cannot plan ahead, they are still able to ignore old targets. These findings suggest that both "what you did" and "what you intend to do" can influence the localization and selection of targets.     

Birth weight and cognitive ability in childhood: a systematic review

Individual differences in cognitive ability may in part have prenatal origins. In high-risk (low birth weight/premature) babies, birth weight correlates positively with cognitive test scores in childhood, but it is unclear whether this holds for those with birth weights in the normal range. The authors systematically reviewed literature on the relationship between normal birth weight (more than 2,500 g) and childhood intelligence in term (37-42-week gestation) deliveries. Six studies met the inclusion criteria, and the authors present a comprehensive narrative review of these studies. There was a small, consistent, positive association between birth weight and childhood cognitive ability, even when corrected for confounders. Parental social class accounted for a larger proportion of the variance than birth weight, and these 2 variables were largely independent.     

All Normal Extensions of S5-squared Are Finitely Axiomatizable

We prove that every normal extension of the bi-modal system S5² is finitely axiomatizable and that every proper normal extension has NP-complete satisfiability problem.Presented by Heinrich Wansing     

Complicating race: the relationship between prejudice, race, and social class categorizations

Although racial stereotyping and prejudice research have received considerable attention, the important element of social class has been largely excluded from social psychological research. Using the Statement Recognition Procedure, two experiments investigated social categorization along race and social class dimensions, the influence of racial and social class prejudice on these categorizations, and differences between White and Black perceivers. Analyses conducted at the subtype of race and social class memberships demonstrated differing patterns of categorization based on subtype membership. For example, lowerclass Black targets were primarily categorized by race, whereas middle-class Black targets were primarily categorized by social class. The results demonstrate the importance of considering social class membership independent of and in conjunction with race. Theoretical and methodological implications regarding the study for race and social class categorizations are discussed.     

Apolipoprotein e gene variability and cognitive functions at age 79: a follow-up of the Scottish mental survey of 1932

Apolipoprotein E (APOE) genotype is a possible influence on nonpathological cognitive aging. The authors studied 462 community-dwelling, 79-year-old people born in 1921, whose childhood IQ had been assessed in the Scottish Mental Survey of 1932 (Scottish Council for Research in Education, 1933). Adjusting for sex, childhood IQ, and self-reported illnesses, the authors found that those with an APOE e4 allele had significantly lower Wechsler Logical Memory (D. Wechsler, 1987) scores than those without an e4 allele. Those people with APOE s2/e3 genotypes had significantly higher Wechsler Logical Memory scores than e3/s3, who were significantly higher than e3/e4. Neither nonverbal reasoning nor verbal fluency were affected. In this sample, APOE genotype contributed to verbal memory in old age.     

Attentional biases for negative interpersonal stimuli in clinical depression

An information-processing paradigm was used to examine attentional biases in clinically depressed participants, participants with generalized anxiety disorder (GAD), and nonpsychiatric control participants for faces expressing sadness, anger, and happiness. Faces were presented for 1000 ms, at which point depressed participants had directed their attention selectively to depression-relevant (i.e., sad) faces. This attentional bias was specific to the emotion of sadness; the depressed participants did not exhibit attentional biases to the angry or happy faces. This bias was also specific to depression; at 1000 ms, participants with GAD were not attending selectively to sad, happy, or anxiety-relevant (i.e., angry) faces. Implications of these findings for both the cognitive and the interpersonal functioning of depressed individuals are discussed and directions for future research are advanced.     

The syllable-based word length effect and stimulus set specificity

The word length effect is the finding that a list of items that take less time to pronounce is better recalled on an immediate serial recall test than an otherwise equivalent list of items that take more time to pronounce. Contrary to the predictions of all major models of the word length effect, Hulme, Suprenant, Bireta, Stuart, and Neath (2004) found that short and long items presented within the same list were recalled equally as well as short items presented in lists of just short items. Different results were reported by Cowan, Baddeley, Elliot, and Norris (2003), who found that mixed lists were recalled worse than pure short lists, but better than pure long lists. The experiments reported here suggest that the different empirical findings are due to properties of the stimulus sets used: one stimulus set produces results that replicate Cowan et al., whereas all other sets tested so far yield results that replicate Hulme et al.