Suicidal Behaviors in Surviving Monozygotic and Dizygotic Co‐Twins: Is the Nature of the Co‐Twin's Cause of Death a Factor?

Genetically informative samples can address hereditary and experiential influences on suicide‐related behaviors. The frequency of suicide‐related behaviors was compared in twins from two survivor groups: (1) those whose co‐twins' deaths were suicides (monozygotic [MZ]: n = 47; dizygotic [DZ]: n = 31), and (2) those whose co‐twins' deaths were nonsuicides (MZ: n = 347; DZ: n = 170). The frequency of suicide attempts among suicide survivors was significantly higher in MZ than DZ twins, while the frequency of suicide attempts among nonsuicide twin survivors did not differ between MZ and DZ twins. Twin concordance for suicide attempts more likely reflects a genetic predisposition than a behavioral reaction to the loss.     

Single-Stage Prediction Models Do Not Explain the Magnitude of Syntactic Disambiguation Difficulty

The disambiguation of a syntactically ambiguous sentence in favor of a less preferred parse can lead to slower reading at the disambiguation point. This phenomenon, referred to as a garden-path effect, has motivated models in which readers initially maintain only a subset of the possible parses of the sentence, and subsequently require time-consuming reanalysis to reconstruct a discarded parse. A more recent proposal argues that the garden-path effect can be reduced to surprisal arising in a fully parallel parser: words consistent with the initially dispreferred but ultimately correct parse are simply less predictable than those consistent with the incorrect parse. Since predictability has pervasive effects in reading far beyond garden-path sentences, this account, which dispenses with reanalysis mechanisms, is more parsimonious. Crucially, it predicts a linear effect of surprisal: the garden-path effect is expected to be proportional to the difference in word surprisal between the ultimately correct and ultimately incorrect interpretations. To test this prediction, we used recurrent neural network language models to estimate word-by-word surprisal for three temporarily ambiguous constructions. We then estimated the slowdown attributed to each bit of surprisal from human self-paced reading times, and used that quantity to predict syntactic disambiguation difficulty. Surprisal successfully predicted the existence of garden-path effects, but drastically underpredicted their magnitude, and failed to predict their relative severity across constructions. We conclude that a full explanation of syntactic disambiguation difficulty may require recovery mechanisms beyond predictability.     

The structure of language abilities at 4 years: a twin study

Normal language development was studied in 310 pairs of 4-year-old twins born in the United Kingdom in 1994. Twins were assessed individually in their homes on a diverse battery of language and nonverbal measures. Rotated factor analyses indicated the presence of a general Language factor (L) as well as a general Nonverbal (NV) factor. Moderate genetic influence was found for both L and NV abilities. Bivariate genetic analysis estimated a genetic correlation of .63 between L and NV abilities, implying that over half of the genetic influence on L overlaps with genetic influence on NV. These results suggest that at age 4, genetic influences on individual differences in language overlap substantially with genetic influences on individual differences in other cognitive abilities, although perhaps less so than later in development.     

Index to Volume 23

Other Index

Index to Volume 23     

An examination of organizational and team commitment in a self-directed team environment

A model hypothesizing differential relationships among predictor variables and individual commitment to the organization and work team was tested. Data from 485 members of sewing teams supported the existence of differential relationships between predictors and organizational and team commitment. In particular, intersender conflict and satisfaction with coworkers were more strongly related to team commitment than to organizational commitment. Resource-related conflict and satisfaction with supervision were more strongly related to organizational commitment than to team commitment. Perceived task interdependence was strongly related to both commitment foci. Contrary to prediction, the relationships between perceived task interdependence and the 2 commitment foci were not significantly different. Relationships with antecedent variables help explain how differential levels of commitment to the 2 foci may be formed. Indirect effects of exogenous variables are reported.     

"Factor analyses of the family assessment device," by Ridenour, Daley, & Reich

Ridenour, Daley, and Reich conducted a series of factor analyses using the correlational matrix of the subscale scores of the Family Assessment Device (FAD), published in Family Process, December, 1999. They conclude that "the FAD subscales be reorganized from their current seven-subscale format" (p. 507). We propose that this suggestion for reorganization is premature and based on the inappropriate application of an "internal consistency" model of scale construction to the FAD. We further suggest that the most important criteria regarding an assessment instrument are those of reliability, validity, and clinical utility. In the absence of this kind of data regarding alternative organizations of the FAD, we believe that the original subscales remain the best choice.     

The role of attitudes and beliefs in differential health care utilisation among Chinese in Singapore

Abstract One hundred and twenty-eight Chinese patients at two Western medical practices and two Chinese medical practices in Singapore completed a questionnaire regarding perceptions of illnesses. Health beliefs and attitudes towards different medical practitioners. Results indicate significant differences between those who consult only allopathic physicians (Western doctors) and those who consult both practitioners of traditional Chinese medicine (sinsehs) and Western doctors. Individuals consulting both Western doctors and sinsehs perceived a smaller proportion of "general" illness attributes (those found in both Western and Chinese medicine) to be relevant to specific diseases and showed greater endorsement of Chinese health beliefs than did individuals seeking help only from Western doctors. Also individuals consulting both types of practitioners expressed less satisfaction with the doctor's treatment than did those consulting only Western doctors and also rated sinsehs as more concerned with patient well-being and as listening more to their patients.