Central interference in driving: is there any stopping the psychological refractory period?

ABSTRACT— Participants attempted to perform two tasks concurrently during simulated driving. In the choice task, they responded either manually or vocally to the number of times a visual or auditory stimulus occurred; in the braking task, they depressed a brake pedal in response to the lead car's brake lights. The time delay between the onset of the tasks' stimuli, or stimulus onset asynchrony (SOA), was varied. The tasks were differentially affected by the manipulations. Brake reaction times increased as SOA was reduced, showing the psychological refractory period effect, whereas the choice task showed large effects of the stimulus and response modalities but only a small effect of SOA. These results demonstrate that a well-practiced "simple" task such as vehicle braking is subject to dual-task slowing and extend the generality of the central-bottleneck model.     

Use of the Personality Assessment Inventory in Assessment of Posttraumatic Stress Disorder in Women

This study investigated the utility of the Personality Assessment Inventory (PAI) for the assessment of posttraumatic stress disorder (PTSD). Participants were 55 community-residing adult women who were administered a comprehensive battery that included the PAI and the Clinician-Administered PTSD Scale (CAPS). Participants were classified as either PTSD or non-PTSD based on the CAPS, and PAI profiles were compared between the two groups. Significant group differences were found for seven PAI clinical scales (Anxiety, Depression, Anxiety-Related Disorders, Somatic Complaints, Paranoia, Borderline Features, and Schizophrenia), one validity scale (Negative Impression), and two treatment scales (Nonsupport and Treatment Rejection). When all PAI scales and component subscales are considered, the largest group differences were found for the physiological subscale of the Depression scale (DEP-P) and the Traumatic Stress subscale of the Anxiety-Related Disorders scale (ARD-T). ARD-T and DEP-P also demonstrated excellent diagnostic utility. Finally, correlations between PAI scales and four CAPS symptom clusters provided additional validity evidence, in particular supporting a distinction between effortful avoidance and numbing. Taken together, these results support the use of the PAI in the assessment of PTSD.This study was the basis of a Masters thesis for Meghan McDevitt-Murphy. Portions of this study were presented at the annual meeting of the Association for Advancement of Behavior Therapy, November 2000.     

How informed is online informed consent?

We examined participants' reading and recall of informed consent documents presented via paper or computer. Within each presentation medium, we presented the document as a continuous or paginated document to simulate common computer and paper presentation formats. Participants took slightly longer to read paginated and computer informed consent documents and recalled slightly more information from the paginated documents. We concluded that obtaining informed consent online is not substantially different than obtaining it via paper presentation. We also provide suggestions for improving informed consent--in both face-to-face and online experiments.     

Selection-for-action in visual search

Grasping an object rather than pointing to it enhances processing of its orientation but not its color. Apparently, visual discrimination is selectively enhanced for a behaviorally relevant feature. In two experiments we investigated the limitations and targets of this bias. Specifically, in Experiment 1 we were interested to find out whether the effect is capacity demanding, therefore we manipulated the set-size of the display. The results indicated a clear cognitive processing capacity requirement, i.e. the magnitude of the effect decreased for a larger set size. Consequently, in Experiment 2, we investigated if the enhancement effect occurs only at the level of behaviorally relevant feature or at a level common to different features. Therefore we manipulated the discriminability of the behaviorally neutral feature (color). Again, results showed that this manipulation influenced the action enhancement of the behaviorally relevant feature. Particularly, the effect of the color manipulation on the action enhancement suggests that the action effect is more likely to bias the competition between different visual features rather than to enhance the processing of the relevant feature. We offer a theoretical account that integrates the action-intention effect within the biased competition model of visual selective attention.     

When does feedback facilitate learning of words?

Some researchers have suggested that although feedback may enhance performance during associative learning, it does so at the expense of later retention. To examine this issue, subjects (N = 258) learned Luganda-English word pairs. After 2 initial exposures to the materials, subjects were tested on each item several times, with the presence and type of feedback varying between subjects. A final test followed after 1 week. Supplying the correct answer after an incorrect response not only improved performance during the initial learning session--it also increased final retention by 494%. On the other hand, feedback after correct responses made little difference either immediately or at a delay, regardless of whether the subject was confident in the response. Practical and theoretical implications are discussed.     

Barriers and Bridges to Intimacy and Mutuality: A Critical Review of Sexual Advice Found in Self-Help Bestsellers

Sexuality in a committed relationship is based ideally on both intimacy and mutuality. Gender socialization may limit women's and men's capacities in these two important areas of sexual relationships. This article describes the results of a content analysis of nine best-selling popular press books on the New York Times Bestseller List between 1988 and 1998 according to their advice related to sexual intimacy and mutuality. Books were analyzed to determine the degree to which they built barriers or bridges to the development of intimacy and mutuality. Results indicate that while most authors offered advice that built bridges to intimacy, several built barriers to the development of mutuality. Implications for therapists are discussed.     

Are cognitive symptoms of schizophrenia mediated by abnormalities in emotional arousal?

We tested 28 individuals with schizophrenia (SZ) and 16 healthy individuals on a test of logical reasoning and "cognitive gating," defined as the ability to discriminate between relevant and irrelevant information in confirming or disconfirming a given belief. The Logical Reasoning and Cognitive Gating Task tests both processes under neutral and affect-laden conditions. This is done by presenting formally identical constructs using benign and emotionally arousing language. When separated by symptom profiles, we found statistically significant differences for performance and arousal response between patients with delusions, patients with formal thought disorder, and patients with neither delusions nor formal thought disorder, as well as between patients and healthy controls. When analyzed by error type, we found that nearly all errors by delusional patients were caused by overly restrictive information choice, a pattern that may be related to a delusional patient's tendency to "jump to conclusions" on Bayesian probabilistic tasks. This is in contrast to patients with formal thought disorder, whose low performance resulted also from overly extensive information choice. The tendencies towards restriction were exacerbated by arousal, which is consistent with studies on cognition and arousal in healthy individuals. After briefly examining research on emotional arousal and SZ, and the interaction between emotional arousal and restriction of perceptual cues in healthy individuals, we conclude by suggesting a model which accounts for the distinctive cognitive characteristics of delusional patients by their possessing distinct vulnerabilities to emotional arousal. Specifically, these results suggest the possibility that delusional patients process information in a manner that is essentially intact. However, delusional patients may possess an acute vulnerability to emotional arousal that might cause delusional individuals to behave cognitively as if they were healthy individuals under significantly more severe forms of stress.