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.     

Deception research involving children: ethical practices and paradoxes

This commentary draws on the thoughtful contemplation and innovative procedures described in the special section articles as well as current professional codes and federal regulations to highlight ethical practices and paradoxes of deception research involving children. The discussion is organized around 4 key decision points for the conduct of responsible deception research involving children: (a) evaluating the scientific validity and social value of deception research within the context of alternative methodologies, (b) avoiding and minimizing experimental risk, (c) the use of child assent procedures as questionable ethical safeguards, and (d) debriefing as both remedy and risk.     

A Comparison of Three Methods of Teaching Skin Self-Examinations

Skin self-examinations are essential for the early identification and treatment of skin cancers. However, little is known about the most effective methods for teaching skin cancer detection and skin self-examination. This study compared three skin cancer education methods that are commonly used in the primary care setting: viewing a videotape, reading brochures, and one-on-one instruction from a nurse practitioner. One hundred forty-three young adults were randomly assigned to one of the four conditions (educational intervention or wait list) and completed measures of skin cancer knowledge, ability to visually discriminate cancerous versus noncancerous skin growths, and behavioral ability to perform a skin self-examination immediately (Time 1) and 3 weeks (Time 2) after the educational intervention. Results showed that participants across all educational interventions had significantly higher skin cancer knowledge compared to those in the wait-list control group, and these knowledge scores were maintained for 3 weeks. Participants in the brochure condition scored significantly higher than participants in all other conditions on an observational measure of skin self-examination. Demographic variables, such as gender and ethnicity, were not found to be related to performance on any of the dependent measures. These findings provide preliminary evidence that knowledge of skin cancer may be enhanced through a variety of educational techniques and that written materials (e.g., brochures) may represent the minimal intervention level necessary for teaching adults how to perform thorough skin self-examinations.