Differential effects of list strength on recollection and familiarity

Numerous studies have found a null list strength effect (LSE) for recognition sensitivity: Strengthening memory traces associated with some studied items does not impair recognition of nonstrengthened studied items. In Experiment 1, the author found a LSE using receiver operating characteristic-based measures of recognition sensitivity. To account for the discrepancy between this and prior research, the author (a) argues that a LSE occurs for recollection but not for discrimination based on familiarity, and (b) presents self-report data consistent with this hypothesis. Experiment 2 tested the dual-process hypothesis more directly, using switched-plurality (SP) lures to isolate the contribution of recollection. There was a significant LSE for comparisons involving SP lures; the LSE for discrimination of studied items and nominally unrelated lures (which can be supported by familiarity) was not significant.     

Cascaded versus noncascaded models of lexical and semantic processing: the turple effect

The density of the orthographic neighborhood surrounding an item has been shown to have an inhibitory effect for nonwords in a lexical decision experiment. Four experiments are reported investigating whether a similar pattern holds for a semantic categorization task (animal vs. non-animal). In the first experiment, no effects of neighborhood density were found for nonexemplars, whether they were words or nonwords. The absence of any inhibitory effect for nonwords implies that close orthographic neighbors are ignored. However, the second experiment showed that if the nonword has a neighbor that is an animal name (eg., turple), an interference effect is observed, implying that neighbors do exert an effect if they have the right semantic properties. The same items showed no additional interference in lexical decision. These results suggest the involvement of semantic properties very early in the processing cycle. A cascaded processing system monitoring activation in semantic features can explain these results, but cannot explain the frequency effect observed for nonexemplar words or the fact that variation in density is irrelevant when one of the neighbors is an exemplar. It is argued that existing models of semantic categorization must be extended to accommodate these results.     

The feature-positive effect in allocations of responsibility for collaborative tasks

People commonly believe they have contributed more to collaborative tasks than others give them credit for. We distinguish between two types of contributions – additions (such as adding words to a co-authored paper) and deletions (such as removing extraneous words) – and show that individuals are especially prone to receive less credit from others than they believe they deserve when their contributions consist of taking something away rather than adding something. Participants who shortened some writing believed they improved it just as much as did participants who lengthened some, but were seen by others as having contributed less. Although one can hardly fail to notice one's own deletions, these contributions – like any contributions that, by their very nature, leave little trace of themselves – are easy for others to overlook.     

Stress in Clinical Psychology Trainees: Current Research Status and Future Directions

The purpose of this article is to present the current status of the literature related to stress in clinical psychology trainees (CPTs), and to offer research directions for investigating stress in this population and ways to enhance self‐care in these individuals. The following conclusions emerge from the review: (1) CPTs are vulnerable to elevated stress; (2) undue stress can negatively impact CPTs' personal and professional functioning and, in turn, result in less than optimal standards of care for clients; (3) there is a dearth of studies on stress in this population and no published intervention studies; (4) incorporating self‐care strategies into clinical psychology training is recommended; and (5) “third‐wave” cognitive behaviour therapy stress management interventions have been efficacious in comparable populations. In view of the potential costs of elevated stress to trainees themselves and their clients, research on stress and stress management in this population is of a high priority. Broad research agendas are proposed for these two domains. Modifications to clinical training programmes to reduce trainee stress are required and should be evidence‐based and systematically revaluated.     

The removal of pluto from the class of planets and homosexuality from the class of psychiatric disorders: a comparison

We compare astronomers' removal of Pluto from the listing of planets and psychiatrists' removal of homosexuality from the listing of mental disorders. Although the political maneuverings that emerged in both controversies are less than scientifically ideal, we argue that competition for "scientific authority" among competing groups is a normal part of scientific progress. In both cases, a complicated relationship between abstract constructs and evidence made the classification problem thorny.     

Genetic and environmental effects on stuttering: a twin study from Finland

The present study explored the prevalence of self-reported stuttering in a Finnish twin population and examined the extent to which the variance in liability to stuttering was attributable to genetic and environmental effects. We analyzed data of 1728 Finnish twins, born between 1961 and 1989. The participants were asked to complete a questionnaire on speech, language, and voice. In two of the questions they were asked to report the occurrence of childhood and present stuttering of their own and that of their sibling. According to the results, 2.3% (52) of the participants were reported to have stuttered as children and 28.8% of them (15) were reported to continue to stutter in adulthood. There was no significant gender difference in the prevalence of stuttering in either childhood or adulthood. For childhood stuttering, the tetrachoric correlation was higher for monozygotic pairs (r=.74) than for dizygotic pairs (r=.27). By means of structural equation modeling it was found that 82% of the variance in liability to childhood stuttering was attributable to additive genetic effects, with the remaining 18% due to non-shared environmental effects. In conclusion, the results of the present study confirm findings from prior studies and support a strong genetic and only a moderate non-shared environmental effect on stuttering. Potential small differences in the prevalence of stuttering in different populations are suggested by our data. EDUCATIONAL OBJECTIVES: The reader will be able to recognize the contribution of genetic and environmental effects on stuttering.     

Undermining the Zeigarnik effect: Another hidden cost of reward

Forty college students participated in a study ostensibly designed to obtain measures of the hemispheric activity while they worked on a spatial reasoning task. In fact, our true interest was in determining whether subjects would return to the spatial reasoning task once the hemispheric recordings were completed. Subjects would normally be expected to return to the task by virtue of the Zeigarnik effect because no subject completed the task during the “hemispheric recording” phase. The manipulation involved telling one group of subjects that they would be paid $1.50 for participating in the study (expected reward group). The remainder of the subjects were not led to expect the reward (unexpected reward group). The result was that 86% of the unexpected reward subjects but only 58% of the expected reward subjects (p < .05) manifested the Zeigarnik effect. This differential tendency to return to the task was further reflected in time differences. The average unexpected reward subject spent 3 min 48 sec of a five-minute free-choice period at the task, whereas the average expected reward subject spent only 2 min 20 sec (p < .05). Reward expectancy, therefore, led to an undermining of the Zeigarnik effect. This observation supports Condry's prediction that rewarding performance at a task can lead to premature task disengagement.     

An application of a biased version of the Bradley-Terry-Luce model to professional basketball results

Some extensions of the Bradley-Terry-Luce model for paired comparisons are presented and used to assess the existence of a home court advantage for professional basketball teams. It is shown how maximum likelihood estimates for these models can be obtained from a simple iterative scaling algorithm. Won-loss records for the regular season are used to make predictions for playoff series. The models are extended to include possible differences among divisions. These models can be applied in many other situations to incorporate group effects and order effects into analysis of paired comparisons.     

Mirror-reading in right- and left-handers

In mirror-reading, words are read from right to left and letters are read in a reverse right-to-left orientation. In one experiment we compared the ability of normal right- and left-handed subjects to mirror-read and found that the left-handers made fewer errors and could read mirror print more rapidly. In a second experiment we attempted to learn whether there is a hemifield superiority for reading mirror words and whether there are any differences between left- and right-handers in a hemifield. We found that although both right- and left-handers more rapidly detected mirror words projected to the left visual half-field, there were no differences between groups. However, in the right visual half-field, the performance of left-handers was superior to that of the right-handers. The results of the hemifield study suggest that left-handers may be superior at reading mirror words because they can more easily reverse their scanning pattern.