Discrimination and generalization by rats of temporal stimuli lasting for minutes

In three experiments, rats learned to respond differentially to reinforced and nonreinforced trials when the length of the intertrial interval (ITI) predicted the trial outcome (reinforcement or nonreinforcement). Rats in control groups, for whom the length of the ITI did not predict the outcome, did not show differential performance on nonreinforced and reinforced trials. Generalization gradients obtained following discrimination training were comparable to those obtained following discrimination training with other types of discriminative stimuli. That is, groups which had shown differential performance in discrimination training yielded generalization gradients with fastest speeds at the previously reinforced ITIs, slowest speeds at the previously nonreinforced ITIs, and intermediate speeds at ITIs of intermediate length. Control groups yielded flat gradients across all ITIs tested. These effects were shown for relative time discrimination (short time = reinforcement, long time = nonreinforcement, or the reverse) and also for an absolute time discrimination (long and short time = reinforcement, middle time = nonreinforcement or the reverse). This method was effective for time duration measured in minutes rather than seconds, as is more commonly the case.     

A low-stress restraint procedure for EEG acquisition in awake rats

A restraint procedure was developed to reduce movement-related artifacts during the acquisition of EEG data from unanesthetized, unparalyzed rats. It combines the low-stress properties of a cloth restraint bag with the improved immobility of a rigid restraint device. The spontaneous behavior of the rat facilitates both the induction of and the subsequent release from restraint.     

The PSYCHLAB programming system: A tool for developing experimental control programs

The PSYCHLAB system is designed to facilitate the task of writing experimental control programs. The system consists of two major components: (1) a collection of procedures and functions to facilitate presenting stimuli, collecting responses, and measuring response times and (2) a high-level language (LAB-TALK) designed to organize and sequence events in experiments. The PSYCHLAB system is formally an interpreter that will interpret programs written in LAB-TALK. The interpreter is customized to perform the detailed functions of each trial in an experiment. The occurrence of these trials is controlled by the LAB-TALK program. Thus, once a particular experimental paradigm has been represented in a customized version of the interpreter, many different experiments in that paradigm can be programmed by variations in the LAB-TALK program.     

The equivalence of three statistical packages for performing hierarchical cluster analysis

Three different software programs which contain hierarchical agglomerative cluster analysis procedures were shown to generate different solutions on the same data set using apparently the same options. The basis for the differences in the solutions was the formulae used to calculate Euclidean distance. Users of statistical software were warned of terminological confusion concerning cluster analysis.This research was supported by a National Science Foundation grant (DCR#74-20007) entitled A Consumer Report on Cluster Analysis Software. I wish to thank the authors of the three programs for their helpful comments on the paper.     

The relationship of sexual attitudes,attitudes about women,and racial attitudes in white males

A questionnaire measuring sexual attitudes, attitudes about women, and racial attitudes was administered to 350 White male college students. Sexual attitudes characterized by sexual guilt, emphasis on personal and social control of sexual expression, and depersonalization of sex were significantly positively correlated (p<.001) with attitudes that typified women in terms of traditional masculine—feminine stereotypes and good (nonsexual)—bad (sexual) dichotomies. These stereotyped and dichotomous attitudes about women and constricted and depersonalized sexual attitudes were both significantly positively correlated (p<.001) with negative racial attitudes. The implications of these results and other research suggested by this investigation are discussed.This report is based on a dissertation submitted in partial fulfillment of the requirements for the Ph.D. degree at Michigan State University, 1973. The author would like to express appreciation to Dozier W. Thornton for continued guidance and assistance as dissertation advisor. In addition, the author gratefully acknowledges the assistance of Donald L. Grummon, Andrew M. Barclay, and Jeanne E. Gullahorn, all of whom served on the dissertation committee.