Probabilistic inference in human semantic memory

The idea of viewing human cognition as a rational solution to computational problems posed by the environment has influenced several recent theories of human memory. The first rational models of memory demonstrated that human memory seems to be remarkably well adapted to environmental statistics but made only minimal assumptions about the form of the environmental information represented in memory. Recently, several probabilistic methods for representing the latent semantic structure of language have been developed, drawing on research in computer science, statistics and computational linguistics. These methods provide a means of extending rational models of memory retrieval to linguistic stimuli, and a way to explore the influence of the statistics of language on human memory.     

On the causal mechanisms of stereotype threat: can skills that don't rely heavily on working memory still be threatened?

Recent work suggests that stereotype threat (ST) harms performance by reducing available working memory capacity. Is this the only mechanism by which ST can occur? Three experiments examined ST's impact on expert golf putting, which is not harmed when working memory is reduced but is hurt when attention is allocated to proceduralized processes that normally run outside working memory. Experiment 1 showed that well learned golf putting is susceptible to ST. Experiments 2 and 3 demonstrated that giving expert golfers a secondary task eliminates ST-induced impairment. Distracting attention away from the stereotype-related behavior eliminates the harmful impact of negative stereotype activation. These results are consistent with explicit monitoring theories of choking under pressure, which suggest that performance degradation can occur when too much attention is allocated to processes that usually run more automatically. Thus, ST alters information processing in multiple ways, inducing performance decrements for different reasons in different tasks.     

Individual differences in second-language proficiency: does musical ability matter?

This study examined the relation between musical ability and second-language (L2) proficiency in adult learners. L2 ability was assessed in four domains: receptive phonology, productive phonology, syntax, and lexical knowledge. Also assessed were various other factors that might explain individual differences in L2 ability, including age of L2 immersion, patterns of language use and exposure, and phonological short-term memory. Hierarchical regression analyses were conducted to determine if musical ability explained any unique variance in each domain of L2 ability after controlling for other relevant factors. Musical ability predicted L2 phonological ability (both receptive and productive) even when controlling for other factors, but did not explain unique variance in L2 syntax or lexical knowledge. These results suggest that musical skills may facilitate the acquisition of L2 sound structure and add to a growing body of evidence linking language and music.     

Reactivity to a laboratory stressor among individuals with bipolar I disorder in full or partial remission

Strong links have been documented between life events and the course of bipolar disorder. Laboratory studies of stress provide an opportunity to understand the mechanisms involved in reactivity to stressors, but few such studies have been done in the bipolar field. In the current study, 28 people with bipolar I disorder in full or partial remission and 40 people with no history of a mood disorder were randomly assigned to 1 of 3 conditions involving different levels of failure feedback on a concept formation task. Confidence, affective reactions, and performance on a subsequent anagram task were assessed. Results provide tentative support for reactivity to the stressor among the bipolar group, although reactivity was limited to impaired anagram performance.     

Utilizing usernames for sex categorization in computer-mediated communication: examining perceptions and accuracy.

As more interpersonal interactions move online, people increasingly get to know and recognize one another by their self-selected identifiers called usernames. Early research predicted that the lack of available cues in text based computer-mediated communication (CMC) would make primitive categories such as biological sex irrelevant in online interactions. Little is known about the types of perceptions people make about one another based on this information, but some limited research has shown that questions about gender are the first to be asked in online interactions and sex categorization has maintained salience. The current project was designed to examine the extent to which individuals might include obvious gender information in their usernames, as well as how easily gender could be attributed from usernames. Seventy-five coders were asked whether or not they could assign 298 people to a sex category based only on their username, and then to rate how confident they were in making the attribution. Results indicated that coders were fairly inaccurate in making these attributions, but moderately confident. Additionally, the results indicated that neither women nor men were more accurate in attributing gender from usernames, and that neither women nor men tended to use more obvious gender markers in their usernames. Additionally, those who did use obvious gender markers in their username tended to have less experience with computer chat. The results are discussed in conjunction with the limitations of the present investigation, and possibilities for future research.     

Direct and indirect effects of third-party relationships on interpersonal trust

Past studies of the determinants of interpersonal trust have focused primarily on how trust forms in isolated dyads. Yet within organizations, trust typically develops between individuals who are embedded in a complex web of existing and potential relationships. In this article, the authors identify 3 alternative ways in which a trustor and trustee may be linked to each other via third parties: network closure (linked via social interactions with third parties), trust transferability (linked via trusted third parties), and structural equivalence (linked via the similarity of their relationships with all potential third parties within the organization). Each of these is argued to influence interpersonal trust via a distinct social mechanism. The authors hypothesized that network closure and structural equivalence would predict interpersonal trust indirectly via their impact on interpersonal organizational citizenship behaviors performed within the interpersonal relationship, whereas trust transferability would predict trust directly. Social network analyses of data gathered from a medium-sized work organization provide substantial support for the hypotheses and also suggest important directions for future research.     

Neuropsychologic functioning in children with autism: further evidence for disordered complex information-processing.

A wide range of abilities was assessed in 56 high-functioning children with autism and 56 age- and IQ-matched controls. Stepwise discriminant analyses produced good group discrimination for sensory-perceptual, motor, complex language, and complex memory domains but lower agreement for the reasoning domain than previously obtained for adults. Group discrimination did not occur for attention, simple language, simple memory, and visuospatial domains. Findings provide additional support for a complex information-processing model for autism, previously based on adult data, demonstrating a pattern across domains of selective impairments on measures with high demands for integration of information and sparing when demands were low. Children as compared to adults with autism exhibited more prominent sensory-perceptual symptoms and less pronounced reasoning deficits reflecting brain maturation.     

The prepared mind: neural activity prior to problem presentation predicts subsequent solution by sudden insight

Insight occurs when problem solutions arise suddenly and seem obviously correct, and is associated with an "Aha!" experience. Prior theorizing concerning preparation that facilitates insight focused on solvers' problem-specific knowledge. We hypothesized that a distinct type of mental preparation, manifested in a distinct brain state, would facilitate insight problem solving independently of problem-specific knowledge. Consistent with this hypothesis, neural activity during a preparatory interval before subjects saw verbal problems predicted which problems they would subsequently solve with, versus without, self-reported insight. Specifically, electroencephalographic topography and frequency (Experiment 1) and functional magnetic resonance imaging signal (Experiment 2) both suggest that mental preparation leading to insight involves heightened activity in medial frontal areas associated with cognitive control and in temporal areas associated with semantic processing. The results for electroencephalographic topography suggest that noninsight preparation, in contrast, involves increased occipital activity consistent with an increase in externally directed visual attention. Thus, general preparatory mechanisms modulate problem-solving strategy.     

Concreteness and item-to-list context associations in the free recall of items differing in context variability

Context variability can be defined as the number of preexperimental contexts in which a given concept appears. Following M. Steyvers and K. J. Malmberg's (2003) work, the authors have shown that concepts that are experienced in fewer preexperimental contexts generally are better remembered in episodic memory tasks than concepts that are experienced in a greater number of preexperimental contexts. The purpose of this article is to demonstrate that low context variability confers its memorial advantage because of stronger item-to-list context associations as compared with high context variability. Three experiments that use environmental context changes from study to test demonstrate that the low context variability advantage is eliminated when item-to-list context associations are not available because of environmental changes at test. In addition, the low context variability advantage is eliminated when inward processing at study prevents the formation of item-to-list context associations.