Sex Differences in Vigilance Performance and Perceived Workload

Female and male subjects monitored the repetitive presentation of a pair of lines for occasional changes in height (spatial task) or duration (temporal task). Perceptual sensitivity for critical signals favored men in the spatial task, whereas no sex differences in signal detectability existed in the temporal task. Measurements of perceived workload using the NASA-TLX scale mirrored these performance effects. Women tended to rate the overall workload associated with the spatial task to be greater in comparison with men. In addition, women found the spatial task to be significantly more frustrating, mentally demanding, and effortful than men did and rated their own performance lower than their male counterparts did. In contrast, no sex-linked differences in perceived workload were noted in regard to the temporal task. The results support the suggestion by Dittmar, Warm, and Dember (1987) that sex differences in sustained attention are task specific.     

Book Notes

Abstract

Identification of Book Reviewers for this Number. William H. Cole is Professor and Chairman of the Department of Biology in Clark Chris.

Anfänge der Reifezeit. By William Stern. Leipzig, Quelle & Meyer. 1925, pp. 125.

Mental Hygiene as Taught by Jesus. By Alexander B. MacLeod. New York, The Macmillan Company. 1925, pp. 138.

The Nature of Intelligence and the Principles of Cognition. By Charles E. Spearman. London, Macmillan and Co., Ltd. 1923, pp. viii+358.

Genetic Studies of Genius. By Lewis M. Terman et Al. California, Stanford University Press. 1925, pp. xv+648.

Principles of Psychotherapy. By Dr. Pierre Janet. New York, The Macmillan Company. 1924, pp. viii+322.

Chimpanzee Intelligence and its Vocal Expressions. by Robert M. Yerkes and Blanche W. Learned. Baltimore, Williams & Wilkins Company. 1925, pp. 157.

Neurological Foundations of Animal Behavior. By C. Judson Herrick. New York, Henry Holt and Company. 1924, pp. xii+334.

Physiological Foundations of Behavior. By Charles M. Child. New York, Henry Holt and Company. 1924, pp. v+330.

The Field of Psychology. By Madison Bentley. New York, D. Appleton and Company, 1925. pp. xvi+545.

Experience and Nature. By John Dewey. Chicago, Open Court Publishing Company. 1925, pp. xi+443.

Abnormal Psychology and Education. By Frank Watts. New York, D. Appleton and Company. 1924, pp. xiv+220.

Psychology for Child Training. By Arland D. Weeks. New York, D. Appleton and Company. 1925, pp. xi+312.

Animals Looking Into the Future. By William A. Kepner. New York, The Macmillan Company. 1925, 197 pp.     

Worry and Sleep Length Revisited: Worry,Sleep Length,and Sleep Disturbance Ascribed to Worry

The author administered university students (N = 222; 152 women, 70 men) the Worry Domains Questionnaire (F. Tallis, G. C. L. Davey, & A. Bond, 1994) and a newly constructed scale (the Sleep Disturbance Ascribed to Worry Scale) to measure sleep disturbance attributed to worry. To revisit previous studies (i.e., E. Hartmann, F. Baekeland, & G. R. Zwilling, 1972; S. J. H. McCann & L. L. Stewin, 1988) that suggested that sleep length was positively related to worry, the author also asked the students a question about habitual sleep length. The results indicated that worry and sleep disturbance attributed to worry were negatively related to sleep length. A regression analysis revealed that worry was significantly negatively related to habitual sleep length irrespective of sleep disturbance ascribed to worry.     

Preliminary Observations on Play Behavior in Puppies

Previous research suggested that the experimenter variable in conservation assessment procedures has not been adequately studied. This experiment investigated the effect of sex of experimenter on length conservation responses in second-grade subjects under group testing procedures. Results of contingency table analysis of observed frequencies suggested that there are significantly more operational conservers under female test administration than under male test administration. Further analysis revealed no significant difference in the number of operational conservers for male and female Ss with either male or female examiners. The sex of experimenter variable does appear to be an important factor in conservation assessment at the lower elementary level.     

Prior distributions for random choice structures

We study various axioms of discrete probabilistic choice, measuring how restrictive they are, both alone and in the presence of other axioms, given a specific class of prior distributions over a complete collection of finite choice probabilities. We do this by using Monte Carlo simulation to compute, for a range of prior distributions, probabilities that various simple and compound axioms hold. For example, the probability of the triangle inequality is usually many orders of magnitude higher than the probability of random utility. While neither the triangle inequality nor weak stochastic transitivity imply the other, the conditional probability that one holds given the other holds is greater than the marginal probability, for all priors in the class we consider. The reciprocal of the prior probability that an axiom holds is an upper bound on the Bayes factor in favor of a restricted model, in which the axiom holds, against an unrestricted model. The relatively high prior probability of the triangle inequality limits the degree of support that data from a single decision maker can provide in its favor. The much lower probability of random utility implies that the Bayes factor in favor of it can be much higher, for suitable data.     

Coordination of Grip Configurations as a Function of Force Output

In this investigation, the authors examined the coordination and control of force production by the digits of the hand as a function of criterion force level and grip configuration. Each adult participant (N = 6: 3 men and 3 women) was required to place the thumb and a finger (or fingers) upon load cells that were fixed to a grasping apparatus that was clamped to a table. In the task, participants had to match a criterion continuous constant total force level displayed on a computer screen. There were 10 trials at each grip configuration and criterion force level combination on each of 3 consecutive days. The results showed that (a) different grip configurations minimized error at each force level; (b) there was a specific digit pairing within a given grip configuration that produced the highest correlation of force output; (c) the correlation between the force output of digits generally increased at higher force levels; (d) error was reduced at each force level and grip configuration over the practice period; and (e) the organization of the force output of each digit varied as a function of digit, force level, grip configuration, and practice. The findings are consistent with the hypothesis that coordination of the digits in prehension is reflective of an adaptive, task-specific solution that is modified with practice.     

Spinal Cord Circuits

Over the past decade, research at three different levels of sensorimotor control has revealed a degree of complexity that challenges traditional hypotheses regarding servocontrol of individual muscles: (a) The connectivity of spinal circuits is much more divergent and convergent than expected. (b) The normal and reflex-induced recruitment of individual muscles and compartments of muscles is more finely controlled than was noted previously. (c) The mechanical interactions among linked skeletal segments and their often multiarticular muscles are neither simple nor intuitively obvious. We have developed a mathematical model of the cat hind limb that permits us to examine the influence of individual muscles on posture and gait. We have used linear quadratic control theory to predict the optimal distribution of feedback from a hypothetical set of proprioceptors, given different assumptions about the behavioral goals of the animal. The changes in these predictions that result from changes in the structure and control objectives of the model may provide insights into the functions actually performed by the various circuits in the spinal cord.