Reaction time as a function of the intensity and probability of occurrence of vibrotactile signals

Three Ss made judgments of the presence or absence of a burst of 60-cps vibration onthe index fingertip.The probability of S’s reporting the presence of a signal was found to be influenced by signal probability and signal intensity. Mean reaction time for reporting the presence of a signal decreased as a function of signal intensity and signal probability whereas mean reaction time for reporting the absence of a signal increased as a function of signal intensity and signal probability. On trials where no signal was presented mean R T for reporting a signal decreased with increases in the signal probability whereas mean RT for reporting the absence of a signal increased with increases in signal probability. The results were interpreted as support for the hypothesis that S’s decision time was longer the closer on the sensory continuum a particular observation was to his criterion.     

VSearch: Macintosh software for experiments in visual search

In this paper, we describe software that turns a Macintosh computer into an off-the-shelf tool for experiments on visual search. Our design goals included portability (between members of the Macintosh computer family and between various research settings), user-friendliness (equivalent to Macintosh programming standards), flexibility (to allow replication and extension of important experiments on visual search), and adaptability (very short design-to-data and data-to-analysis turnaround times). We describe how the software meets these goals in three major phases of an experiment: stimulus construction, experimental control, and statistical analysis. We then list several landmark studies of visual search that can be easily designed and extended with the software. Finally, we outline plans for expanding the experimental variations that will be supported in future versions of the software.     

Assessing Adolescent and Adult Attachment: A Review of Current Self-Report Measures

Increased interest in attachment theory among counseling researchers and practitioners has led to the development of several measures of attachment-related constructs. Following a brief overview of the theoretical foundations of attachment theory as conceptualized by Ainsworth (1989) and Bowlby (1988), the authors of this article review four self-report measures of adolescent and adult attachment. Many considerations for the selection and use of these instruments in future counseling research and assessment are discussed.     

The effects of exposure to different sources of sexual information on sexual behavior: Comparing a “sex-expert system” to other educational material

Sexpert, an expert computer program designed to counsel couples on their sexual relationships, was evaluated. Eighty-one heterosexual couples were assigned to one of three experimental manipulations (Sexpert, video, and self-help book) or a control condition. Daily sexual behavior monitoring forms and structured retrospective reports served as measures of baseline and post-manipulation behavior. Daily monitoring of sexual behavior failed to show significant changes occurring after the manipulations. However, retrospective data concerning the postmanipulation period show that compared with the control, the Sexpert, video, and book manipulations had a significant positive impact on couples’ sexual behavior, communication, and learning about sexuality. Sexpert, video, and book were similarly evaluated, except that Sexpert was evaluated as more engaging. In addition, subjects retrospectively reported positive changes in communication, relationship satisfaction, and sexual behavior during the baseline period. This suggests that daily behavioral monitoring is intrusive and may confound the variables measured by it.     

Relation of parental support and control to adolescents' externalizing symptomatology and substance use: A longitudinal examination of curvilinear effects

Past research has generated inconsistent findings regarding the relation of parental control and support to adolescent problem behaviors. Using two waves of data collected 1 year apart, the current study examined the influence of parental control and support on adolescents' externalizing symptoms, alcohol use, and illicit substance use. A sample of adolescents and their parents (@#@ N =454) was studied, within which approximately half of the adolescents were at high risk because of parental alcoholism. Multipleregression analyses of crosssectional data showed a negative quadratic relation between parental control and adolescent externalizing symptomatology, and between parental control and adolescent illicit substance use. Parental control had a negative linear relation to adolescent alcohol use. Parental support showed a negative quadratic relation to adolescent illicit substance use, and negative linear relations to adolescent alcohol use and externalizing symptoms. Although longitudinally adjusted contemporaneous results were consistent with crosssectional findings, parental support and control were prospectively related only to adolescent alcohol use. The quadratic relations suggest that adolescents who receive either extreme of parental support or control are at risk for problem behaviors.     

On becoming a leader: Effects of gender and cultural differences on power distance reduction

The present research focused on power processes in a simulated organizational structure consisting of three hierarchical levels occupied by different numbers of mules and females. Subjects were presented with a chart showing the organizational hierarchy of which they were a member placed at the lowest level, and asked to nominate any person for the leader position vacated by the current incumbent. The results of Experiment I (n = 88 Dutch male and female university students) showed that male subjects strongly overnominated themselves, whereas a majority of the female subjects nominated either self or another female. Of the others that were nominated by both males and females, almost all were occupants of positions immediately below the leader position, indicating the normative influence of a bureaucratic rule of leader succession. Experiment 2 was a replicational study carried out in a different culture (n = lOl Polish male and female university students). Polish subjects adhered to the bureaucratic rule more strongly than their Dutch counterparts, and both females and males nominated mostly males. Results are discussed with reference to gender self-stereotypes and cultural differences.     

IMPROVED CURVEBALL HITTING THROUGH THE ENHANCEMENT OF VISUAL CUES

This study investigated the effectiveness of using visual cues to highlight the seams of baseballs to improve the hitting of curveballs. Five undergraduate varsity baseball team candidates served as subjects. Behavior change was assessed through an alternating treatments design involving unmarked balls and two treatment conditions that included baseballs with 1/4-in. and 1/8-in. orange stripes marking the seams of the baseballs. Results indicated that subjects hit a greater percentage of marked than unmarked balls. These results suggest that the addition of visual cues may be a significant and beneficial technique to enhance hitting performance. Further research is suggested regarding the training procedures, effect of feedback, rate of fading cues, generalization to live pitching, and generalization to other types of pitches.