Opposing effects of age and reading ability on pseudoword priming

Repetition priming refers to the facilitation of stimulus processing due to prior processing of the same or similar stimulus, and is one of the most primitive ways in which experience and practice can affect performance. Previous studies have produced contradictory results regarding the stability of repetition priming across development. Drawing on models of word priming that suggest decreased priming with increased reading ability, the present experiment investigated the possibility that null effects of age in priming are due to opposing effects of age and reading ability on priming magnitude. Forty-eight participants between 7 and 22 years old read aloud primed and unprimed pseudowords, after completing a reading ability assessment. In line with predictions, the magnitude of priming for pseudowords increased with increased age when reading ability was controlled, and decreased with increased reading ability when age was controlled. Moreover, neither the age nor ability effect was significant when tested without the other. Results were not influenced by explicit memory for primed pseudowords. Thus, the present experiment provides evidence for developmental increases in word priming, as well as a potential explanation for the lack of developmental effects in previous studies.     

A new dynamical model of brainstorming: Linear, nonlinear, continuous (simultaneous) and impulsive (sequential) cases

In this paper, we extended the linear dynamical model of [Brown, V., Paulus, P. B. (1996). A simple dynamic model of social factors in group brainstorming. Small Group Research, 27, 91-114] on two accounts. First, we modelled the sequential type brainstorming using impulsive differential equations by treating each category as an impulse and tested its validity in the two experiments that investigated and demonstrated the beneficial effects of sequential priming and memory in individual brainstorming. Finally, we considered the nonlinear case of brainstorming in writing or brainwriting where dyads exchanged their ideas in a written format and that eliminated negative factors occurring in oral brainstorming (e.g., evaluation apprehension, free-riding, production blocking) and enhanced the upward performance matching, and conducted the second experiment in order to test its validity in this paradigm with the effects of sequential priming and memory. Comparisons showed good agreement between results of experiments and those of the mathematical model.     

Counterfactual thinking and confidence in blackjack: A test of the counterfactual inflation hypothesis

This research tests the idea that repeatedly generating counterfactual thoughts in response to recurring events can lead to impairments in memory for actual outcomes (i.e., counterfactual inflation hypothesis). Participants (N = 56) played 40 games of blackjack and listed their thoughts after each win. They were instructed to list evaluative counterfactuals, reflective counterfactuals, or any thoughts that came to mind following each loss. Because reflective counterfactuals focus only on the alternatives to reality, and not in addition to reality (like evaluative counterfactuals), they were expected to lead to the greatest degree of overestimations of performance and confidence for future blackjack playing. The results confirmed this hypothesis, and also demonstrated that the relationship between thought-listing instructions and confidence for the future was mediated by overestimations of performance. Thus, repeatedly generating reflective counterfactual thoughts appears to lead to a special case of imagination inflation with dysfunctional implications for future confidence and risk-taking.     

A model of working memory capacity in the radial-arm maze task

The radial arm maze is one of the most commonly used tests for assessing working memory in laboratory animals. However, to date, there exists no quantitative method of estimating working memory capacity from performance on this task. Here, we present a mathematical model of performance on the radial arm maze from which we can derive estimates of capacity. We derive explicit results for the two most commonly used measures of performance as functions of number of arms in the maze and memory capacity, assuming a uniform random search. We simulate random non-uniform search strategies. Comparing our model to previous experiments, we show that our model predicts a working memory capacity in the range of 3-9 at the level of performance observed in these experiments. This estimate is within the typical estimate of human working memory capacity. Performance of rats on large mazes (e.g. 48 arms) has been used as evidence that the working memory capacity of rats may be significantly larger than that of humans. We report that memory capacity in the range 3-9 is sufficient to explain the performance of rats in very large radial mazes. Furthermore, when we simulate non-uniform random search strategies observed in the experiments, the resulting estimates do not differ significantly from those assuming a uniform random search. We conclude that a list-based model of working memory with modest capacity is more powerful than previously expected.     

Visual attention capacity: a review of TVA-based patient studies

Psychophysical studies have identified two distinct limitations of visual attention capacity: processing speed and apprehension span. Using a simple test, these cognitive factors can be analyzed by Bundesen's Theory of Visual Attention (TVA). The method has strong specificity and sensitivity, and measurements are highly reliable. As the method is theoretically founded, it also has high validity. TVA-based assessment has recently been used to investigate a broad range of neuropsychological and neurological conditions. We present the method, including the experimental paradigm and practical guidelines to patient testing, and review existing TVA-based patient studies organized by lesion anatomy. Lesions in three anatomical regions affect visual capacity: The parietal lobes, frontal cortex and basal ganglia, and extrastriate cortex. Visual capacity thus depends on large, bilaterally distributed anatomical networks that include several regions outside the visual system. The two visual capacity parameters are functionally separable, but seem to rely on largely overlapping brain areas.     

Sibling differentials in power and memory conformity

How much a person conforms to another person's memory report can depend on the power and credibility of this person, even if these factors are manipulated by the experimenter. The aim of the current study was to establish whether memory conformity is also affected by power in pairs involving natural power differentials, in this case siblings. Pairs of adult siblings were shown 50 photographs of faces and then given a recognition test where one partner had to answer before the other. The findings showed that what one sibling reported affected what the other one reported. Contrary to our expectations, however, there was no significant difference in conformity between the younger and the older sibling. The implications of these findings are discussed.     

Multi-Modal CTL: Completeness,Complexity, and an Application

We define a multi-modal version of Computation Tree Logic (ctl) by extending the language with path quantifiers E ^δ and A ^δ where δ denotes one of finitely many dimensions, interpreted over Kripke structures with one total relation for each dimension. As expected, the logic is axiomatised by taking a copy of a ctl axiomatisation for each dimension. Completeness is proved by employing the completeness result for ctl to obtain a model along each dimension in turn. We also show that the logic is decidable and that its satisfiability problem is no harder than the corresponding problem for ctl. We then demonstrate how Normative Systems can be conceived as a natural interpretation of such a multi-dimensional ctl logic. Presented by Jacek Malinowski     

Two are better than one: comparison influences infants' visual recognition memory

Despite a large literature on infants’ memory for visually presented stimuli, the processes underlying visual memory are not well understood. Two studies with 4-month-olds (N = 60) examined the effects of providing opportunities for comparison of items on infants’ memory for those items. Experiment 1 revealed that 4-month-olds failed to show evidence of memory for an item presented during familiarization in a standard task (i.e., when only one item was presented during familiarization). In Experiment 2, infants showed robust memory for one of two different items presented during familiarization. Thus, infants’ memory for the distinctive features of individual items was enhanced when they could compare items.     

Processing efficiency in preschoolers’ memory span: Individual differences related to age and anxiety

In self-paced auditory memory span tasks, the microanalysis of response timing measures represents a developmentally sensitive measure, providing insights into the development of distinct processing rates during recall performance. The current study first examined the effects of age and trait anxiety on span accuracy (effectiveness) and response timing (efficiency) measures from word and digit span performance in a preschool sample (N = 76, mean age = 57 months, SD = 11). Children were reassessed 8 months later using the same two tasks plus a test of nonword memory span and a measure of articulation rate. The results at the second time point (T2) confirmed the effects of age on both processing effectiveness and efficiency. Trait anxiety was an additional negative predictor of span effectiveness (especially for digit span) and efficiency (in the case of word and nonword span). The findings are discussed in the context of factors contributing to early short-term memory development and attentional control theory.