Individual differences in conflict-monitoring: testing means and covariance hypothesis about the Simon and the Eriksen Flanker task

Conflict and context slow-down have been proposed as indicators of a conflict-monitoring system that initiates cognitive control to resolve conflicts in information processing. We investigated individual differences in conflict-monitoring and their associations with working memory (WM) and impulsivity. A total of 150 adults completed a Simon and an Eriksen flanker task, together with measures of WM and impulsivity. On both tasks, responses were slower and less accurate on incompatible than on compatible trials (conflict effect), and the conflict effect was larger when the preceding trial was compatible than when it was incompatible (context effect). Stimulus repetition did not explain the context effect. Individual differences could be attributed to three separable factors for each task: general speeded performance, conflict effect, and context effect. Evidence for across-task generality of these factors was sparse. Associations of these factors with impulsivity were weak at best. WM was correlated with general speed, and also with some but not all factors reflecting conflict-related processes.     

Sequential or parallel decomposed processing of two-digit numbers? Evidence from eye-tracking

While reaction time data have shown that decomposed processing of two-digit numbers occurs, there is little evidence about how decomposed processing functions. Poltrock and Schwartz (1984) argued that multi-digit numbers are compared in a sequential digit-by-digit fashion starting at the leftmost digit pair. In contrast, Nuerk and Willmes (2005) favoured parallel processing of the digits constituting a number. These models (i.e., sequential decomposition, parallel decomposition) make different predictions regarding the fixation pattern in a two-digit number magnitude comparison task and can therefore be differentiated by eye fixation data. We tested these models by evaluating participants' eye fixation behaviour while selecting the larger of two numbers. The stimulus set consisted of within-decade comparisons (e.g., 53_57) and between-decade comparisons (e.g., 42_57). The between-decade comparisons were further divided into compatible and incompatible trials (cf. Nuerk, Weger, & Willmes, 2001) and trials with different decade and unit distances. The observed fixation pattern implies that the comparison of two-digit numbers is not executed by sequentially comparing decade and unit digits as proposed by Poltrock and Schwartz (1984) but rather in a decomposed but parallel fashion. Moreover, the present fixation data provide first evidence that digit processing in multi-digit numbers is not a pure bottom-up effect, but is also influenced by top-down factors. Finally, implications for multi-digit number processing beyond the range of two-digit numbers are discussed.     

Reliability in Content Analysis

In a recent article in this journal, Lombard, Snyder‐Duch, and Bracken (2002) surveyed 200 content analyses for their reporting of reliability tests, compared the virtues and drawbacks of five popular reliability measures, and proposed guidelines and standards for their use. Their discussion revealed that numerous misconceptions circulate in the content analysis literature regarding how these measures behave and can aid or deceive content analysts in their effort to ensure the reliability of their data. This article proposes three conditions for statistical measures to serve as indices of the reliability of data and examines the mathematical structure and the behavior of the five coefficients discussed by the authors, as well as two others. It compares common beliefs about these coefficients with what they actually do and concludes with alternative recommendations for testing reliability in content analysis and similar data‐making efforts.     

Mood-congruent and mood-incongruent learning

We report two experiments that investigate the effect of an induced mood on the incidental learning of emotionally toned words. Subjects were put in a happy or sad mood by means of a suggestion technique and rated the emotional valence of a list of words. Later on, they were asked to recall the words in a neutral mood. For words with a strong emotional valence, mood-congruent learning was observed: strongly unpleasant words were recalled better by sad subjects and strongly pleasant words were recalled better by happy subjects. The reverse was true for slightly toned words: here, mood-incongruent learning was observed. Both effects are predicted by a two component processing model that specifies the effect of the mood on the cognitive processes during learning. Further evidence for the model is given by rating times measured in Experiment 2.     

Optical magnification as event information

Summary The geometrical optics of approach events is delineated. It is shown that optical magnification provides information about distance and time until collision. An experiment is described in which two objects - white styropor® spheres 10 cm in diameter, seen against a white plaster wall - were moved simultaneously at equal, constant speed along straight, converging paths at eye level towards a human observer and towards a common, virtual point of collision which either coincided with the observer's station point or was placed in front of, or behind, that point. Approach events differed with regard to trajectories, distances, velocities, and times-to-collision involved. Events were observed monocularly fixating and binocularly non-fixating, without head movements. The objects always stopped before colliding, and subjects had to respond to the virtual collisions. Most responses were too early, especially for impending collisions at, or behind the observers' station point. Responses for impending collisions in front of the observers tended to be too late, especially for larger total amounts of optical magnification and higher velocities, which together imply shorter times-to-collision. Relative errors were comparatively larger for very short and very long times-to-collision throughout, where events of the first kind were overshot, the latter ones undershot. Results are interpreted with reference to biological theories and the constraints imposed by geometrical optics. Special attention is focused on the issue of unavoidable, necessary confounding of variables in time-to-collision studies.     

Measures of national stereotypes as predictors of the latencies of inductive versus deductive stereotypic judgements

According to Taifel's accentuation theory, national stereotypes can be thought of as the correlation between trait dimensions and national affiliations, This correlation is high when the trait shows high homogeneity within and high distinctiveness between the national groups. The present study tested the hypothesis that a trait's distinctiveness would facilitate inductive stereotypic judgements (inferences from trait to nationality) whereas homogeneity would facilitate deductive stereotypic judgements (inferences from nationality to trait). The latencies of inductive and deductive stereotypic judgements of 48 German subjects were assessed for 39 traits and three foreign nationalities (English, French, Italian). Multiple regression analyses using latencies for both types of judgements us criterion variables and both distinctiveness and homogeneity as predictor variables were conducted. The stereotype measures of Katz and Braly and McCauley and Stitt served as additional predictor variables. As expected from accentuation theory, distinctiveness predicted inductive but not deductive latencies, whereas homogeneity predicted deductive but not inductive latencies. For the latencies of deductive stereotypic judgements, the stereotype measure of Katz and Braly as well as that of McCauley and Stitt also proved to be significant predictors. The results are discussed and recommendations are given with respect to the assessment of national stereotypes.