Relations between visceral and behavioral function in men at bedrest

Multiple physiological measurements as well as a self-assessment of arousal was made in eight men on the first, third, and fifth days of bedrest. On the third day, additional measurements of performance on memory and dexterity tasks were made. Univariate analysis did not reveal any physiological variable to either predict subsequent performance well or to co-vary acutely with it; however, self-rating scores did prove to be useful predictors of subsequent performance. Principal components analysis suggested an“alertness” factor comprised of physiological measures as well as selfratings which helped in predicting better performance. Although the individual patterns of correlations between variables on each of the three test days was variable, even more variability between subjects was found on the performance testing day. We believe this effect of behavioral activation may be due to the injection of common, slow temporal trends into many of the different data sets.     

Processing sets of letters for order: Evidence from reaction time experiments

In two experiments, subjects were required to impose different levels of organization on randomly ordered letters. In a between-subject design, the subject was to identify the letter in the set coming first in the alphabet or to reorganize the set into an alphabetic sequence. In a within-subject design, presentation of the letters was followed by an instruction to carry out the identification or reorganization task or to recite the letters in left-to-right order. Reaction time varied systematically with level of required organization, size of the presented set, and position and spacing of the letter set in the alphabet. The results are discussed in terms of two simple models.     

Daily and major life events: A test of an integrative model of psychosocial stress

The hypothesis that negative daily events mediate the relationship between major negative events and psychological symptomatology was tested using a three-wave, three-variable panel design. Measures of major and daily life events and psychological symptomatology were administered to 58 older adolescents at three time points during the transition from high school to college. The results indicated that the pathways from major life events to daily events and from daily events to psychological symptomatology were significant at each of the time points, but that the direct pathways from major events to psychological symptomatology were not significant at any time point. Thus, the hypothesis was fully supported. The findings are discussed in light of their implications for an integrative theory of the process by which major and daily events have an effect on psychological symptomatology.     

A computer-oriented system for high-speed recording of operant behavior

A method is described by which large quantities of data, generated at high and variable rates from a large number of test boxes, are recorded on a single eight-channel punched paper tape. The data, which include a record of the occurrence time of each event in 1/10-sec units, are in a compact form, suitable for conversion to standard Hollerith punched card codes and for decoding and summarizing by a large digital computer. Experience with the system has demonstrated a high degree of accuracy and reliability, and low operating cost.