Aging increases inattentional blindness to the gorilla in our midst.

When engaged in an attention-demanding task, people are surprisingly vulnerable to inattentional blindness—the failure to notice an unexpected event. Two theories of cognitive aging, attentional capacity models and inhibitory deficit models, make opposite predictions about age differences in susceptibility to inattentional blindness. We tested these predictions using an inattentional blindness paradigm developed by Simons and Chabris (1999) and found that older adults were more likely to experience inattentional blindness than young adults. These results are compatible with attentional capacity models of cognitive aging but not with current inhibitory deficit models. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Attention set for number: Expectation and perceptual load in inattentional blindness.

Inattentional blindness is the failure to detect unexpected events when attention is otherwise engaged. Previous research indicates that inattentional blindness increases as perceptual demands intensify. The authors present 6 cuing experiments that manipulated both the perceptual demands of a primary letter-naming task and the expectations of the individual. Inattentional blindness was greatest for individuals who held a numerical expectation that was consistent with the number of primary-task items presented. Expectation also affected detection differentially at various levels of perceptual load: Detection at moderate and high perceptual load was significantly affected by expectation, whereas detection at low perceptual load was not. The authors suggest that at moderate to high levels of perceptual load, individuals whose numerical expectations are fulfilled terminate processing when the primary task is complete, at the expense of the unexpected visual event. These experiments provide compelling evidence that expectations do affect detection of an unexpected stimulus, and they are the first to demonstrate that individuals set their attention for the number of items to be detected and are vulnerable to inattentional blindness whenever their primary-task numerical expectation is fulfilled. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in working memory capacity predict retrieval-induced forgetting.

Selectively retrieving a subset of previously studied information enhances memory for the retrieved information but causes forgetting of related, nonretrieved information. Such retrieval-induced forgetting (RIF) has often been attributed to inhibitory executive-control processes that supposedly suppress the nonretrieved items' memory representation. Here, we examined the role of working memory capacity (WMC) in young adults' RIF. WMC was assessed by means of the operation span task. Results revealed a positive relationship between WMC and RIF, with high-WMC individuals showing more RIF than low-WMC individuals. In contrast, individuals showed enhanced memory for retrieved information regardless of WMC. The results are consistent with previous individual-differences work that suggests a close link between WMC and inhibitory efficiency. In particular, the finding supports the inhibitory executive-control account of RIF. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Focusing the spotlight: Individual differences in visual attention control.

A time-course analysis of visual attention focusing (attentional constraint) was conducted in groups of participants with high and low working memory spans, a dimension the authors have argued reflects the ability to control attention. In 4 experiments, participants performed the Eriksen flanker paradigm under increasing levels of speed stress. Conditional accuracy functions were derived to measure the time course of attentional constraint. The data showed that accuracy rates rose toward asymptote at different rates, with participants with high working memory spans reaching peak performance before participants with low working memory spans. The authors interpret these data in terms of a rate of attention constraint model. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Working memory capacity and categorization: Individual differences and modeling.

Working memory is crucial for many higher-level cognitive functions, ranging from mental arithmetic to reasoning and problem solving. Likewise, the ability to learn and categorize novel concepts forms an indispensable part of human cognition. However, very little is known about the relationship between working memory and categorization, and modeling in category learning has thus far been largely uninformed by knowledge about people's memory processes. This article reports a large study (N = 113) that related people's working memory capacity (WMC) to their category-learning performance using the 6 problem types of Shepard, Hovland, and Jenkins (1961). Structural equation modeling revealed a strong relationship between WMC and category learning, with a single latent variable accommodating performance on all 6 problems. A model of categorization (the Attention Learning COVEring map, ALCOVE; Kruschke, 1992) was fit to the individual data and a single latent variable was sufficient to capture the variation among associative learning parameters across all problems. The data and modeling suggest that working memory mediates category learning across a broad range of tasks. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Individual differences in working memory capacity and episodic retrieval: Examining the dynamics of delayed and continuous distractor free recall.

Two experiments explored the possibility that individual differences in working memory capacity (WMC) partially reflect differences in the size of the search set from which items are retrieved. High- and low-WMC individuals were tested in delayed (Experiment 1) and continuous distractor (Experiment 2) free recall with varying list lengths. Across both experiments low-WMC individuals recalled fewer items than high-WMC individuals, recalled more previous list intrusions than high-WMC individuals, and recalled at a slower rate than high-WMC individuals. It is argued that low-WMC individuals' episodic retrieval deficits are partially due to the fact that these individuals search through a larger set of items than high-WMC individuals. Simulations based on a random search model were consistent with these general conclusions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual skill differences and large-scale environmental learning.

Spatial skills are known to vary widely among normal individuals. This project was designed to address whether these individual differences are differentially related to large-scale environmental learning from route (ground-level) and survey (aerial) perspectives. Participants learned two virtual environments (route and survey) with limited exposure and tested on judgments about relative locations of objects. They also performed a series of spatial and nonspatial component skill tests. With limited learning, performance after route encoding was worse than performance after survey encoding. Furthermore, performance after route and survey encoding appeared to be preferentially linked to perspective and object-based transformations, respectively. Together, the results provide clues to how different skills might be engaged by different individuals for the same goal of learning a large-scale environment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in components of reaction time distributions and their relations to working memory and intelligence.

The authors bring together approaches from cognitive and individual differences psychology to model characteristics of reaction time distributions beyond measures of central tendency. Ex-Gaussian distributions and a diffusion model approach are used to describe individuals' reaction time data. The authors identified common latent factors for each of the 3 ex-Gaussian parameters and for 3 parameters central to the diffusion model using structural equation modeling for a battery of choice reaction tasks. These factors had differential relations to criterion constructs. Parameters reflecting the tail of the distribution (i.e., τ in the ex-Gaussian and drift rate in the diffusion model) were the strongest unique predictors of working memory, reasoning, and psychometric speed. Theories of controlled attention and binding are discussed as potential theoretical explanations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in working memory: Introduction to the special section.

This special section includes a set of 5 articles that examine the nature of inter- and intraindividual differences in working memory, using working memory span tasks as the main research tools. These span tasks are different from traditional short-term memory spans (e.g., digit or word span) in that they require participants to maintain some target memory items (e.g., words) while simultaneously performing some other tasks (e.g., reading sentences). In this introduction, a brief discussion of these working memory span tasks and their characteristics is provided first. This is followed by an overview of 2 major theoretic issues that are addressed by the subsequent articles—(a) the factors influencing the inter- and intraindividual differences in working memory performance and (b) the domain generality versus domain specificity of working memory—and also of some important issues that must be kept in mind when readers try to evaluate the claims regarding these 2 theoretical issues. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Load induced blindness.

Although the perceptual load theory of attention has stimulated a great deal of research, evidence for the role of perceptual load in determining perception has typically relied on indirect measures that infer perception from distractor effects on reaction times or neural activity (see N. Lavie, 2005, for a review). Here we varied the level of perceptual load in a letter-search task and assessed its effect on the conscious perception of a search-irrelevant shape stimulus appearing in the periphery, using a direct measure of awareness (present/absent reports). Detection sensitivity (d′) was consistently reduced with high, compared to low, perceptual load but was unaffected by the level of working memory load. Because alternative accounts in terms of expectation, memory, response bias, and goal-neglect due to the more strenuous high load task were ruled out, these experiments clearly demonstrate that high perceptual load determines conscious perception, impairing the ability to merely detect the presence of a stimulus--a phenomenon of load induced blindness. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

New rule use drives the relation between working memory capacity and Raven's Advanced Progressive Matrices.

The correlation between individual differences in working memory capacity and performance on the Raven's Advanced Progressive Matrices (RAPM) is well documented yet poorly understood. The present work proposes a new explanation: that the need to use a new combination of rules on RAPM problems drives the relation between performance and working memory capacity scores. Evidence for this account is supported by an item-based analysis of performance during standard administration of the RAPM and an experiment that manipulates the need to use new rule combinations across 2 subsets of RAPM items. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Working Memory Capacity and the Antisaccade Task: Individual Differences in Voluntary Saccade Control.

Performance on antisaccade trials requires the inhibition of a prepotent response (i.e., don't look at the flashing cue) and the generation and execution of a correct saccade in the opposite direction. The authors attempted to further specify the role of working memory (WM) span differences in the antisaccade task. They tested high- and low-span individuals on variants of prosaccade and antisaccade trials in which an eye movement is the sole requirement. In 3 experiments, they demonstrated the importance of WM span differences in both suppression of a reflexive saccade and generation of a volitional eye movement. The results support the contention that individual differences in WM span are not exclusively due to differences in inhibition but also reflect differences in directing the focus of attention. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in reaction to failure-induced stress.

"The McKinney Reporting Test and the MMPI were administered to samples of aviation cadets, aircraft commanders, copilots, and ROTC student officers. Two criterion groups representing the extremes in adjustment were selected within each of the military samples… . There was an overall-significant tendency among the low adjustment cases for those who shifted toward more accurate performance on the McKinney stress period to answer on the Hy scale… like Janet's psychasthenic type, and for those who became more inaccurate to answer like the hysteric. This tendency did not hold for high adjustment cases." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in dream recall.

Ss who typically fail to remember dreams at home (nonreporters) and Ss who frequently remember dreams (reporters) slept in the laboratory for 4 nights each. Gradual or abrupt awakenings were made at each EEG Stage-I REM (dream) period. Although nonreporters and reporters did not differ in REM-period frequency or EEG patterns during sleep, nonreporters did report dreaming less frequently following REM-period awakenings. Ss showed self-consistency in frequency of dream reporting and in type of failure to report. Some nonreporters typically failed to remember any content; others typically said they were awake and thinking. Comparisons among reporters and sub-groups of nonreporters for eye-movement frequency, arousal threshold, and dreamlike-report content indicate that it may be useful to distinguish different kinds of nonreporters. (17 ref.) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in beliefs about groups.

The current research examined individual differences in peoples' positive versus negative beliefs about groups. Three studies were conducted to develop and validate a 16-item Beliefs About Groups (BAG) scale. Factor analyses in Studies 1 and 2 identified and replicated a 4-factor solution, with factors reflecting preferences for group versus individual work, positive group performance beliefs, negative group performance beliefs, and beliefs that others will work hard on group tasks. Study 2 also provided evidence for convergent and divergent validity, and explored relationships between the Big Five personality dimensions and group beliefs. Study 3 provided evidence for test–retest reliability. Across these 3 studies, the BAG scale had total score alphas ranging from .83 to .88. Implications of beliefs about groups for member motivation and group performance, as well as for future research and practice, are highlighted. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The components of working memory updating: An experimental decomposition and individual differences.

Working memory updating (WMU) has been identified as a cognitive function of prime importance for everyday tasks and has also been found to be a significant predictor of higher mental abilities. Yet, little is known about the constituent processes of WMU. We suggest that operations required in a typical WMU task can be decomposed into 3 major component processes: retrieval, transformation, and substitution. We report a large-scale experiment that instantiated all possible combinations of those 3 component processes. Results show that the 3 components make independent contributions to updating performance. We additionally present structural equation models that link WMU task performance and working memory capacity (WMC) measures. These feature the methodological advancement of estimating interindividual covariation and experimental effects on mean updating measures simultaneously. The modeling results imply that WMC is a strong predictor of WMU skills in general, although some component processes—in particular, substitution skills—were independent of WMC. Hence, the reported predictive power of WMU measures may rely largely on common WM functions also measured in typical WMC tasks, although substitution skills may make an independent contribution to predicting higher mental abilities. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual differences in preferences to photographs.

Individual differences in preferences to photographs were explored based on an alternative framework. This framework predicts that the primary difference between individuals in this respect is their ability to process photographic information, which in turn influences their preferences. Chiefly, people with well-developed schemes in photography (e.g., photo professionals) should have a higher ability to process photographic information than people with less developed schemes (e.g., psychology students). Consequently, people with well-developed schemes in photography should prefer photographs that are relatively more demanding to process. Ten psychology students and 5 photo professionals assessed 32 photographs on six general concepts: Preference, Hedonic Tone, Expressiveness, Familiarity, Uncertainty, and Dynamics. As predicted, photo professionals had a higher ability to process photographic information and preferred photographs that were relatively uncertain and unfamiliar. These results are in concordance with previous research and give strong support to the utility of the present framework in experimental aesthetics. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The contributions of primary and secondary memory to working memory capacity: An individual differences analysis of immediate free recall.

The present study tested the dual-component model of working memory capacity (WMC) by examining estimates of primary memory and secondary memory from an immediate free recall task. Participants completed multiple measures of WMC and general intellectual ability as well as multiple trials of an immediate free recall task. It was demonstrated that there are 2 sources of variance (primary memory and secondary memory) in immediate free recall and that, further, these 2 sources of variance accounted for independent variation in WMC. Together, these results are consistent with a dual-component model of WMC reflecting individual differences in maintenance in primary memory and in retrieval from secondary memory. Theoretical implications for working memory and dual-component models of free recall are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Individual and situational differences in desire for certainty.

The correlation was determined between Ss' extremity of response on several attitude and judgment instruments and scores on a test of desire for certainty. "Significant correlations were obtained between response extremity and test scores, suggesting that individual differences in desire for certainty are consistent from one measure to another." In another study it was shown that the strength of the desire for certainty can be increased and decreased by situational influences. 24 references. (PsycINFO Database Record (c) 2010 APA, all rights reserved)