Testing overall and moderator effects in random effects meta‐regression

Random effects meta‐regression is a technique to synthesize results of multiple studies. It allows for a test of an overall effect, as well as for tests of effects of study characteristics, that is, (discrete or continuous) moderator effects. We describe various procedures to test moderator effects: the z, t, likelihood ratio (LR), Bartlett‐corrected LR (BcLR), and resampling tests. We compare the Type I error of these tests, and conclude that the common z test, and to a lesser extent the LR test, do not perform well since they may yield Type I error rates appreciably larger than the chosen alpha. The error rate of the resampling test is accurate, closely followed by the BcLR test. The error rate of the t test is less accurate but arguably tolerable. With respect to statistical power, the BcLR and t tests slightly outperform the resampling test. Therefore, our recommendation is to use either the resampling or the BcLR test. If these statistics are unavailable, then the t test should be used since it is certainly superior to the z test.     

Is all sparing created equal? Comparing lag-1 sparing and extended sparing in temporal object perception

When two targets (T1, T2) are presented amongst a rapid stream of distractors, T2 accuracy is impaired if the targets are separated by at least one distractor (attentional blink). However, this impairment largely disappears if the targets follow one another directly (lag-1 sparing), and, in fact, as many as four or five consecutive targets may be identified quite accurately under these conditions (extended sparing). Although all current models propose a common mechanism for both lag-1 and extended sparing, this hypothesis has yet to be tested. To this end, we examined the effect of various types of attentional switches, known to impact lag-1 sparing, on extended sparing in order to determine whether they would have a similar effect. Results suggested substantial parallels between the two types of sparing. We discuss these results in terms of a unified account of sparing in temporal object perception.     

Stigmatizing attitudes of the community towards people living with HIV/AIDS

This research involved an exploratory study in which a questionnaire was used to investigate the personal stigma and perceived community stigma regarding HIV/AIDS in a South African community. Student fieldworkers interviewed a convenient sample of 901 respondents from different races, gender and age groups, and found that respondents tended towards stigmatizing persons with HIV/AIDS. Yet, this degree of stigmatization was significantly less severe than the degree of stigmatization that respondents attributed to the community at large. Altogether 17% of the respondents had high stigmatizing attitudes, while 42% perceived the stigmatization by others in the community to be high. Race group, personal knowledge of someone with HIV, area of residence, gender and age group impacted on the respondents' personal tendency to stigmatize those with HIV/AIDS. The article discusses the difference between the level of personal stigma attached by the respondents and that perceived by them to be attached by the community. Attention is also paid to the possible implications of stigmatizing behaviour patterns and interventions on a community level. Copyright © 2006 John Wiley & Sons, Ltd.     

Unraveling the Wonder of the Ordinary: A Narrative Analysis of Meaning Construction in Memories of Familiar Routines

Familiar routines may be a source of meaning, but just as well become habitual and lose meaning. To understand this paradox, a narrative approach was used to explore how meaning is constructed in memories of familiar routines. Two types were distinguished: routines of transition and routines of harmony. Results show how meaning construction may relate to the contrast between instrumental acts in the memories and their higher purpose. In routines of transition, meaning may emerge through a temporal transformation, while routines of harmony may become meaningful through the awareness of contrasting evaluations within the routine or a contrasting wider context.     

Spatial but not temporal cueing influences the mislocalisation of a target flashed during smooth pursuit

Human subjects misjudge the position of a target that is flashed during a pursuit eye movement. Their judgments are biased in the direction in which the eyes are moving. We investigated whether this bias can be reduced by making the appearance of the flash more predictable. In the normal condition, subjects pursued a moving target that flashed somewhere along its trajectory. After the presentation, they indicated where they had seen the flash. The mislocalisations in this condition were compared to mislocalisations in conditions in which the subjects were given information about when or where the flash would come. This information consisted of giving two warning flashes spaced at equal intervals before the target flash, of giving two warning beeps spaced at equal intervals before the target flash, or of showing the same stimulus twice. Showing the same stimulus twice significantly reduced the mislocalisation. The other conditions did not. We interpret this as indicating that it is not predictability as such that influences the performance, but the fact that the target appears at a spatially cued position. This was supported by a second experiment, in which we examined whether subjects make smaller misjudgments when they have to determine the distance between a target flashed during pursuit and a reference seen previously, than when they have to determine the distance between the flashed target and a reference seen afterwards. This was indeed the case, presumably because the reference provided a spatial cue for the flash when it was presented first. We conclude that a spatial cue reduces the mislocalisation of targets that are flashed during pursuit eye movements. The cue does not have to be exactly at the same position as the flash.     

Hypochondriacs' estimation of negative outcomes: domain-specificity and responsiveness to reassuring and alarming information

Based on hypochondriacal patients' tendency to overestimate the seriousness of bodily sensations and health risks [Barsky, A. J., Wyshak, G. & Klerman, G. L. (1990). The Somatosensory Amplification Scale and its relationship to hypochondriasis. Journal of Psychiatric Research, 24, 323-334; Warwick, H. M. C., & Salkovskis, P. M. (1990). Hypochondriasis. Behaviour Research and Therapy, 28, 105-117], we investigated whether hypochondriacal individuals (n = 20) are inclined to report higher estimates of negative outcomes than healthy controls (n = 20) when interpreting ambiguous health-related and nonhealth-related events. In addition, we explored the influence of additional reassuring and alarming information on hypochondriacs' estimates of negative outcomes. Following the cognitive-behavioural model of hypochondriasis [Warwick, H. M. C. & Salkovskis, P. M. (1989). Hypochondriasis. In J. Scott, J. M. G. Williams & A. T. Beck (Eds.), Cognitive therapy in clinical practice: an illustrative casebook. (pp. 78-102). London: Routledge] we hypothesized that hypochondriacal individuals would be more responsive to alarming information and less responsive to reassuring information than healthy controls. Yet, hypochondriacs were neither found to be immune for reassuring information, nor to be hypersensitive to alarming information. Meanwhile, irrespective of the additional alarming or reassuring information, hypochondriacs clearly showed a domain-specific bias towards higher estimates of negative outcomes in ambiguous health-related situations.     

Direct estimates of processing delays in the attentional blink

 When two targets (T1 and T2) are presented in rapid succession, identification of T2 is often impaired (attentional blink: AB). The two-stage model accounts for the AB deficit by assuming that: (a) T2 is delayed in Stage 1 while Stage 2 is busy processing T1, and (b) T2 is vulnerable to masking while delayed. We report converging evidence for the model by evaluating these assumptions independently of the AB deficit itself. The results show that: (a) response times for T2 identification decreased as the lag between T1 and T2 was increased; (b) response times for T2 decreased across lags only if T1 was masked; and (c) accuracy of T2 identification increased as the stimulus-onset asynchrony between T2 and the trailing mask was increased. Received: 4 February 1999 / Accepted: 26 July 1999     

Gregory Bateson on deutero-learning and double bind: a brief conceptual history

The concepts of deutero-learning and double bind have acquired an increasingly important status in various fields of social and behavioral science, particularly in psychiatry, psychotherapy, organization, and policy science. With this proliferation, however, their original meaning and significance has become increasingly muted. In this article it is argued that both concepts are important ingredients of a behavioral theory of (organizational) learning. To support this argument, the development of both concepts is traced to the work of Gregory Bateson. In Bateson's thinking, the two concepts have a firm base in dyadic behavior and interaction.     

Attitudes in the social context: the impact of social network composition on individual-level attitude strength

Four studies, using both experimental and correlational designs, explored the implications of being embedded within attitudinally congruent versus attitudinally heterogeneous social networks for individual-level attitude strength. Individuals embedded within congruent social networks (i.e., made up of others with similar views) were more resistant to attitude change than were individuals embedded within heterogeneous social networks (i.e., made up of others with a range of views). Mediational evidence suggests that attitudinally congruous social networks may increase attitude strength by decreasing attitudinal ambivalence and perhaps by increasing the certainty with which people hold their attitudes. These results suggest that features of the social context in which an attitude is held have important implications for individual-level attitude strength.     

Rapid serial visual distraction: task-irrelevant items can produce an attentional blink

When two sequential targets (T1 and T2) are presented within about 600 msec, perception of the second target is impaired. This attentional blink (AB) has been studied by means of two paradigms: rapid serial visual presentation (RSVP), in which targets are embedded in a stream of central distractors, and the two-target paradigm, in which targets are presented eccentrically without distractors. We examined the role of distractors in the AB, using a modified two-target paradigm with a central stream of task-irrelevant distractors. In six experiments, the RSVP stream of distractors substantially impaired identification of both T1 and T2, but only when the distractors shared common characteristics with the targets. Without such commonalities, the distractors had no effect on performance. This points to the subjects' attentional control setting as an important factor in the AB deficit and suggests a conceptual link between the AB and a form of nonspatial contingent capture attributable to distractor processing.