Effects of false increasing,decreasing, and true electromyographic biofeedback on the frequency of stuttering

Adult stutterers received auditory feedback of laryngeal area muscle activity while reading aloud under three conditions: (1) False Increasing Feedback, (2) False Decreasing Feedback, and (3) True Feedback. The subjects were unaware that the feedback in two conditions was being altered and were instructed not to manipulate the feedback signal. Decreases in the frequency of stuttering were observed for both the false increase and true feedback conditions. Factors contributing to the effectiveness of biofeedback techniques with stutterers are discussed.     

Impact of Firearm Availability and Gun Regulation on State Suicide Rates

Past studies on suicide have investigated the association of firearm ownership and suicide risk in the United States. The aim of the present study was to build on previous work by examining the impact of firearm storage practices and the strictness of firearm regulation on suicide rates at the state level. Data were compiled from primarily three sources. Suicide and firearm ownership information was obtained from the Centers for Disease Control and Prevention. Strictness of handgun regulation was derived from figures available at the Law Center to Prevent Violence, and controls were taken from the US Bureau of the Census. Mixed models were fitted to the data. Household firearm ownership was strongly associated with both suicide by all mechanisms, and firearm suicide. Storage practices had especially elevated consequences on suicide rates. Percent with loaded guns and gun readiness increased suicide rates, and strictness of gun regulation reduced suicide rates. Ready access to firearms can make a difference between life and death. Loaded and unlocked firearms within reach become risk factors for fatal outcomes from suicidal behavior. Future research might want to examine ways of obtaining more recent data on individual firearm ownership. This study proposes several policy recommendations for suicide prevention.     

Moving with the in-crowd: Cooperation and interpersonal entrainment in in- vs. out- groups

Current Psychology - Interpersonal entrainment or moving together in time, has been shown to cultivate pro-social behaviours amongst those who take part. Converging evidence suggests that its...     

Prior experience and patterning in a prisoner's dilemma game

Female college students first played a pseudo-prisoner's dilemma (PPD) game with the experimenter, who followed a fixed strategy. In the first experiment the experimenter's strategies for different groups of subjects were: (a) play tit-for-tat; (b) play randomly; (c) always cooperate; (d) always defect (‘cooperation’ and ‘defection’, defined as in an actual prisoner's dilemma game). Only the tit-for-tat group increased cooperation over trials; other groups decreased cooperation. After playing the PPD with the experimenter, subjects played an actual prisoner's dilemma (PD) game with each other. In the PD game, subjects began cooperating moderately but cooperation deteriorated regardless of what the experimenter's strategy had been in the earlier (PPD) game. In a second experiment, subjects again played a PPD game with the experimenter and then played a PD game with each other. Half played one trial at a time as in the first experiment while half played in patterns of four trials at a time. In the PD game, patterning of trials retarded the development of mutual defection regardless of previous experience. The cooperation-preserving effect of patterning of trials in this social task is compared with similar effects on individual tasks involving self-control and risk-aversion. © 1998 John Wiley & Sons, Ltd.     

Subjective probability and delay.

Human subjects indicated their preference between a hypothetical $1,000 reward available with various probabilities or delays and a certain reward of variable amount available immediately. The function relating the amount of the certain-immediate reward subjectively equivalent to the delayed $1,000 reward had the same general shape (hyperbolic) as the function found by Mazur (1987) to describe pigeons' delay discounting. The function relating the certain-immediate amount of money subjectively equivalent to the probabilistic $1,000 reward was also hyperbolic, provided that the stated probability was transformed to odds against winning. In a second experiment, when human subjects chose between a delayed $1,000 reward and a probabilistic $1,000 reward, delay was proportional to the same odds-against transformation of the probability to which it was subjectively equivalent.     

Sex differences in impulsivity: a meta-analysis

Men are overrepresented in socially problematic behaviors, such as aggression and criminal behavior, which have been linked to impulsivity. Our review of impulsivity is organized around the tripartite theoretical distinction between reward hypersensitivity, punishment hyposensitivity, and inadequate effortful control. Drawing on evolutionary, criminological, developmental, and personality theories, we predicted that sex differences would be most pronounced in risky activities with men demonstrating greater sensation seeking, greater reward sensitivity, and lower punishment sensitivity. We predicted a small female advantage in effortful control. We analyzed 741 effect sizes from 277 studies, including psychometric and behavioral measures. Women were consistently more punishment sensitive (d = -0.33), but men did not show greater reward sensitivity (d = 0.01). Men showed significantly higher sensation seeking on questionnaire measures (d = 0.41) and on a behavioral risk-taking task (d = 0.36). Questionnaire measures of deficits in effortful control showed a very modest effect size in the male direction (d = 0.08). Sex differences were not found on delay discounting or executive function tasks. The results indicate a stronger sex difference in motivational rather than effortful or executive forms of behavior control. Specifically, they support evolutionary and biological theories of risk taking predicated on sex differences in punishment sensitivity. A clearer understanding of sex differences in impulsivity depends upon recognizing important distinctions between sensation seeking and impulsivity, between executive and effortful forms of control, and between impulsivity as a deficit and as a trait.     

Knowledge of natural kinds in semantic dementia and Alzheimer's disease

We examined the semantic impairment for natural kinds in patients with probable Alzheimer's disease (AD) and semantic dementia (SD) using an inductive reasoning paradigm. To learn about the relationships between natural kind exemplars and how these are distinguished from manufactured artifacts, subjects judged the strength of arguments such as "Humans have a chemical called sebum. Therefore, frogs have a chemical called sebum." These judgments depend on subjects' perception of the similarity between the familiar objects named in the premise and the conclusion. Controls rated arguments generalizing from a natural kind to an artifact as significantly weaker than arguments generalizing from one natural kind to another natural kind. SD patients demonstrated a graded profile of generalization without evidence of a categorical distinction between natural kinds and artifacts. AD patients' judgments also suggested more difficulty than controls at distinguishing between natural kinds and artifacts. Both SD patients and AD patients resembled controls in their judgments of arguments where both objects are from the natural kinds category. Semantic knowledge thus appears to be sufficiently preserved in both AD and SD to support within-category similarity judgments. We suggest that SD patients may be impaired in part at identifying the features critical to diagnosing membership in a semantic category, while AD patients' performance is consistent with their semantic categorization deficit.     

Information structure expectations in sentence comprehension

In English, new information typically appears late in the sentence, as does primary accent. Because of this tendency, perceivers might expect the final constituent or constituents of a sentence to contain informational focus. This expectation should in turn affect how they comprehend focus-sensitive constructions such as ellipsis sentences. Results from four experiments on sluicing sentences (e.g., The mobster implicated the thug, but we can't find out who else) suggest that perceivers do prefer to place focus late in the sentence, though that preference can be mitigated by prosodic information (pitch accents, Experiment 2) or syntactic information (clefted sentences, Experiment 3) indicating that focus is located elsewhere. Furthermore, it is not necessarily the direct object, but the informationally focused constituent that is the preferred antecedent (Experiment 4). Expectations regarding the information structure of a sentence, which are only partly cancellable by means of overt focus markers, may explain persistent biases in ellipsis resolution.     

A Study of the Benefit of Social and Religious Support on Church Members During Times of Crisis

A majority of Americans participate in religious services and identify themselves as members of a faith community. Understanding the role that religion plays in people's lives is essential to developing a comprehensive model of social support during times of crisis. The purpose of the current study was to identify the resources of social support that are helpful for church members during times of crisis. Although research on the impact of social support has identified several types of support—and the function of such support—to people undergoing difficult times, researchers have not looked at the impact of religious beliefs and participation in religious communities on social support to any significant extent. The current study collected questionnaire data from 23 members of one congregation who experienced a personal crisis. Analysis of the data shows that religious beliefs and the support provided by the religious community were seen as extremely helpful in times of crisis. Implications for incorporating people's religious beliefs and participation in religious communities into future investigations of social support are discussed.