Form and exploration of mechanical stability limits in erect stance

The stability limits of erect stance are described as a geometrical structure in a movement space. Mechanical properties and response latency, a neural property, are determining factors for the stability limits. Standing stability limits of adults and young children are compared, and a simple scheme is suggested by means of which infants can discover the stability limits as they learn to stand. The mechanics of different standing movements are discussed because their spatial temporal properties relate directly to their different stability limits. The combination of the stability limits for different movements gives a total set of stability limits, a different structure for adults than for children.     

On task and theory specificity

One of the significant limitations of the motor control and skill acquisition domain is that the theories, models, and hypotheses are, in most cases, task specific. Many lines of theorizing fail to hold up under even small changes in task constraints, although clearly the field does have some robust phenomena. It is proposed that a broader consideration of the role of task constraints, which is grounded in the methodology of nonlinear dynamics, may help to formulate a more general action theory of coordination and control.     

Cheating following success and failure in heavy and moderate social drinkers

Two groups of American undergraduates (moderate and heavy social drinkers) completed a matrix task and received either positive or negative feedback on their performance. Following this they were given a maze task, which was designed so that cheating could be detected. Heavy drinkers cheated more than moderate drinkers under success conditions (positive feedback). Heavy drinkers who received positive feedback also cheated more than heavy drinkers who received negative feedback. The results are interpreted in terms of self-handicapping theory.     

EVALUATION OF TACTILE PROMPTS WITH A STUDENT WHO IS DEAF,BLIND, AND MENTALLY RETARDED

We provided tactile cues to a student who was deaf, blind, and mentally retarded to guide her performance on a variety of packaging tasks. The student had previously received extensive training on multiple packaging and sequencing tasks through her vocational education program. Although she was able to complete these tasks, each change in materials necessitated that similar levels of retraining be conducted in order for her to perform revised tasks. Tactile cues were introduced and evaluated through a multiple baseline with sequential withdrawal design for two envelope-stuffing tasks and one bagging task. Results indicated that the tactile prompts were effective in guiding her performance on the training task and in promoting generalization to novel tasks and cues. Continued use of the cues was necessary to maintain the student's performance. Our findings suggest that tactile prompts function similarly to picture prompts and may be an effective alternative external prompting system for persons for whom picture prompts would not be appropriate.     

Sex roles, gender, and fear

Male and female college students classified as masculine, feminine, androgynous, or undifferentiated on the Bem (1974) Sex Role Inventory (N = 199) were given the Wolpe (1969) Fear Inventory. Significant differences in average fear scores were seen between men and women and between the four sex-role categories, with sex role and gender contributing equally to the variability. The argument is raised here that excessive fearfulness or fearlessness might be as much a product of sex-role conditioning as a product of gender.