Hypnosis, reporting bias, and suggested negative hallucinations.

We examined the role of reporting bias in hypnotic negative hallucinations by using a paradigm in which reporting bias was assessed independently of perceptual change. In Experiment 1, highly hypnotizable subjects reported significant loudness reductions when tested for hypnotic deafness. Later, however, these subjects biased their reported loudness reductions in the absence of perceptual change, and their reporting bias scores were almost as large as their hypnotic deafness reports. Subjects also biased their ratings of strategy use. In Experiment 2, ratings of blindness given in response to a hypnotic negative visual hallucination suggestion were significantly correlated with reporting bias scores obtained in this paradigm. Although hypnotic blindness and hypnotic deafness correlated significantly, the partial correlation between these variables was nonsignificant when reporting bias scores were statistically controlled. Theoretical implications are discussed.     

Hypnotically created pseudomemories: further investigation into the "memory distortion or response bias" question.

In order to study whether pseudomemories represent actual memory distortions or are a result of response bias, 60 highly hypnotizable subjects and subjects from the general population were divided into 4 experimental groups and were tested for pseudomemory manifestation after receiving a false suggestion. Of the 4 groups of subjects, 3 were offered a monetary reward as a motivation to distinguish false suggestion from actual occurrence. Pseudomemory manifestation was found to be significantly higher among subjects not offered a reward than among subjects who were offered such an reward. The implications of these findings are discussed.     

Relationship of racial stressors to blood pressure responses and anger expression in black college students

The physiological effects of racism, as a stressor, were examined as they related to blood pressure (BP) and anger experiences in Black college students. Current research has failed to consider the stressful effects of racism as a factor contributing to the higher incidence of essential hypertension among Blacks. Twenty-seven Black college students viewed three excerpts showing racist situations involving Blacks; anger-provoking, nonracist situations; and neutral situations. After each scene, BP was taken, and a mood checklist was administered. The Framingham Anger Scale and the Anger Expression Scale were administered. Analyses revealed that BP significantly increased during the presentation of racist stimuli but not of anger-provoking or neutral stimuli. Self-reports of state anger, as measured by the mood checklist, were significant for both the anger-provoking and racist stimuli. BP scores were significantly correlated to the two trait anger measures. Exposure to racist stimuli was associated with BP increases among Blacks. Such cumulative exposure to racism may have important implications for the etiology of essential hypertension.     

Prediction accuracy of text recall: Ease, effort and familiarity

Prediction accuracy of text recall was studied in two experiments. Text characteristics (i.e., consistency and distinctiveness) were manipulated in Experiment 1, and familiarity with the reading-task in Experiment 2. The results were also analyzed and discussed in terms of easy processing (Experiment 1), and in terms of increased and more active processing (Experiment 2). Text characteristics did not affect prediction accuracy. However, being familiar with the reading-task led to good and long-lasting prediction accuracy. Thus, subjects reading a school-book text, instructed to learn the contents of it demonstrated reliable memory awareness, both for immediate recall and for delay of one week. It was also suggested that increased processing demands and active reading enhances prediction accuracy.     

Driving assessment with computer-video scenarios: More is sometimes better

Several factors are critical in designing effective simulator systems for driving research and driver assessment. First, there is cost, in terms of which, less is better. Costly systems are sometimes fine for specific research purposes, but they are impractical for most other purposes. Second, there is realism; in this case, more may be better, but we don’t know how much realism is really necessary for good prediction of actual driving behaviors. Recent evidence suggests that real-world clutter may enhance prediction, but it also makes interpreting research more difficult. More realism may increase cost, but this is not necessarily the case. Third, there is user-friendliness, in terms of which, again, more is better. Systems that are easier to operate require less-highly trained personnel; hence, increasing user-friendliness also decreases cost, especially for assessment. We demonstrated a highly user-friendly, low-cost, moderately realistic, and partly interactive computer-video driving research and assessment system. In recent research, we obtained multipleR values ofA7 for older drivers with only three to four scenarios predicting a real-world crash index.     

Explanation and the theory of questions

In The Scientific Image B. C. van Fraassen argues that a theory of explanation ought to take the form of a theory of why-questions, and a theory of this form is what he provides. Van Fraassen's account of explanation is good, as far as it goes. In particular, van Fraassen's theory of why-questions adds considerable illumination to the problem of alternative explanations in psychodynamics. But van Fraassen's theory is incomplete because it ignores those classes of explanations that are answers not to why-questions but to how-questions. In this article I provide a unified theory of explanatory questions that comprehends both how-questions and why-questions, and I show that a question-theoretic approach to explanation can be defended independently of van Fraassen's programme of Constructive Empiricism.     

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.