A reflection: Howard Scott Liddell, 1895-1962

Howard S. Liddell, Professor of Psychobiology in the Department of Psychology at Cornell University, was one of the earliest American students and developers of I.P. Pavlov's theory of the conditioned reflex and an early researcher on stress. The significance of Liddell's work on stress was fully recognized when he was sent, as a member of a commission, to the battlefront at the height of the Korean War to study stress and self-control in the soldiers. This profound experience convinced Liddell that behavioral research must ultimately be made relevant to the understanding and elevation of human behavior. He spent the remaining ten years of his life in efforts to implement this conviction through research, writing, and lectures before scientific and lay groups.     

Students' attitudes toward university health services

This study measured students' attitudes toward a university's student health services (SHS) and identified factors that were related to their attitudes. A questionnaire surveying students' attitudes was administered to a sample of 150 students at the Oxford Campus of the University of Mississippi. Analysis of the data revealed that students' attitudes had a statistically significant correlation with the following variables: perceived medical care cost, amount of health information/education received during medical encounters, time spent in the waiting room of the SHS, sex of the student, and income of the student. There was no significant relationship between attitude and age.     

Self-control behavior in hyperactive and nonhyperactive children

This study was aimed at evaluating the self-control behaviors of hyperactive (HA) and nonhyperactive (NHA) first-grade pupils under conditions of repeated failure on a previously learned concept formation task. Subjects were divided into HA and NHA groups on the basis of their scores on the Conners (1969) Teacher Rating Scale. During the training stage of the experiment the children learned a concept formation task under a schedule of contingent positive reinforcement. In the test stage they performed the same task but under a negative noncontingent reinforcement schedule. The results revealed no differences in initial rate of learning the task between the groups. After the introduction of the negative noncontingent reinforcement schedule, however, the HA group showed a marked decrease in the use of effective problem-solving strategies. The HA children's performance on the concept formation task was accompanied by the emission of negative self-evaluations and solution-irrelevant statements. The NHA group used significantly more statements showing useful goal directed cognitive mediations than the HA children. The results suggested that HA children may have deficits in self-control skills.Grateful acknowledgment is made to the two anonymous reviewers whose insightful comments were very helpful in producing the final form of this paper.     

The 3RT Test: Three reaction time tasks for IBM PC computers

The 3RT Test consists of a simple, a choice, and a conditional reaction time (RT) task. The three tasks involve comparable visual stimuli and require identical manual responses, but they differ in the complexity of cognitive processing required. The nonverbal stimuli convey commonly known meanings. Responses can be made either on the keyboard or on response keys connected to the computer’s serial port. The computer’s internal timer/counter is used for millisecond timing. The test administration program allows flexible setting of the test conditions. The data analysis program provides summary data not only for each RT task as a whole, but also for separate trial types within each task. Summary statistics include measures of variation and central value that are not affected by extreme scores. In addition to laboratory studies with normal adults, the 3RT Test is suitable for life-span developmental studies, cross-cultural comparisons, and other uses in various clinical settings.     

Gestural beats: The rhythm hypothesis

Gestural beats are typically small up and down or back and forth flicks of one or both hands. It has been assumed by researchers hypothesizing about the interaction of beats and speech that beats coincide with verbal stress. Microanalysis shows that gestural beats are organized in rhythmic patterns and do not necessarily cooccur with stressed syllables as previously assumed. Tone group nuclei appear to function as gestational points for rhythmic groups, which supports the theory that thinking utilizes words as cognitive tools and provides evidence that in some cases entire tone units are formed in advance. Evidence of an interpersonal gestural rhythm is also presented.This research was supported by grants from the National Science Foundation and from the American Association of University Women Educational Foundation.     

Human sensitivity to temporal proximity: The role of spatial and temporal speed gradients

Estimates of temporal proximity (sometimes called time-to-collision) from random-dot flow patterns are shown to be based upon retinal speed, rather than upon changes in dot density. Neither the spatial nor the temporal gradient of motion is essential to the task, but estimates can be made from either alone. Performance is unaffected by the addition of rotational motion, suggesting that observers axe capable of extracting the radial component of motion, which contains all the relevant information, from complex stimuli.