A two-process theory of the spacing (lag) effect in free recall is presented and tested. (Editor/RK)

Experiments to probe the nature of one mode of thinking, imagined spatial operations, have been devised. Results confirm that the mind can model physical processes, subjecting them to the geometric constraints that hold in the external world. The experimental work and implications are discussed in detail. (MNS)

A theoretical analysis and a review of the uses of role playing and deception methods indicates that role playing methods are based on a more comprehensive and inclusive conceptualization of human behavior than are deception methods, and that role playing assumptions are better able to account for the empirical findings in research on the behavior…

Reports on experiments designed to explore the way the processing unit depends on the information in the component letters and the information contained in their arrangements in a familiar letter string. Hypotheses were tested by degrading the quality of individual letters and by spacing the letters irregularly. (CLK)

Two experiments using the same Ss in one sitting tested the hypothesis that the temporal redundancy inherent in rhythmically structured sound sequences is used during listening by the perceptual mechanism. (Editor)

Article gives the results of a multiple-probe recognition memory investigation examining the importance of relationships between items in a memorized series (positive set). (Editor)

Discusses the original and new methods of personnel recruitment and selection utilized by the Peace Corps, stressing the need for a body of rigorous experimental studies supporting scientific procedures in this area; and reports a study of Peace Corpsmen in the South Pacific. (JM)

Author reviews a book on America's founder of research in child study, G. Stanley Hall, and suggests omissions which could have made it more interesting. (RK)

Address presented at the annual meeting of the Eastern Psychological Association, New York City, April 1971. Research started under a grant from the National Aeronautics and Space Administration and completed and reported under a grant from the National Science Foundation, Office of Science Information Service. (VM)

Paper read at Conference on New Approaches to Behavioral Research on Smoking sponsored by the American Cancer Society in Tucson, Arizona, on March 30 and 31, 1972. (DS)

To discover how students felt about being experimental subjects, 152 introductory psychology student research subjects answered questionnaires about their evaluation of the experience. Results showed that, while students were aware of low-level coercion, they found the experience worthwhile and did not object to receiving extra credit as a reward.…

A study used two-dimensional recall to identify the units of recall in the process of remembering, in order to investigate the correspondence of experimentally identified memory units to theoretically defined propositional units, and the correspondence of recall organization to story schema. (Author/AM)

Reports on experiments examining the semantic organization of concrete nouns and verbs and its development in childhood. Differences in semantic organization are said to be a clue to age-related changes in performance with verbs. (AM)

Psychophysical procedures provide the simplest method for studying time discrimination of animals. This experiment examines the psychological threshold of rats in estimating the time of occurrence of an event and how they adjust their behavior accordingly. Further research may determine the theoretical implications for both animals and people.…