Decisions about life and death: Assessing the Law Reform Commission and the Presidential Commission Reports

This paper compares and critically comments upon certain aspects of the Canadian Law Reform Commission Report,Euthanasia, Aiding Suicide and Cessation of Treatment, and the United States Presidential Commission Report,Deciding to Forego Life-Sustaining Treatment. It focuses on their positions on euthanasia and on the general principles, values, and procedures that ought to govern practices of foregoing life-sustaining treatment. The paper first comments on the recent debate over the moral relevance of the killing/letting die distinction, since this issue appears crucial in assessing the rationality of the current, absolute prohibitions of direct killing in medical contexts, embodied both in law and in codes of ethics. This issue bears upon a question in the closing section—whether the withdrawal of foods and fluids is ever morally permissible.     

Beyond the relational principle of reinforcement

Behavior under baseline conditions in which the contingency is absent can shed some light on the individual's performance under a schedule, but is insufficient as a basis for prediction of performance. This insufficiency of the baseline data runs counter to a recent formalization of the relational principle of reinforcement (Donahoe, 1977). A more satisfactory predictive model must incorporate not only the baseline level of the instrumental response and that of the contingent response, but also the schedule requirements, the character of each response in relation to the other, and the behavior required in simply switching from each to the other.     

Behavioral coaching in the development of skills in football, gymnastics, and tennis

A review of the literature indicates that methods of skill acquisition based on the operant paradigm have been scientifically validated with many motor behaviors. However, these procedures have been limited to the use of positive reinforcement for correct performance when applied to the acquisition of complex sports skills in natural settings. To find complementary procedures to enhance skill acquisition, a coaching method involving several behavioral techniques was developed that focused on remediation of errors. This coaching method combined the following components: (1) systematic use of verbal instructions and feedback, (2) positive and negative reinforcement, (3) positive practice, and (4) time out. Three sports, football, gymnastics, and tennis, were selected to determine the effectiveness and generality of this behavioral coaching method. A total of 23 male and female subjects, ranging in age from 11 to 35, was included in this study. Baseline data were first collected for each sport under standard coaching conditions. Next, the behavioral coaching method was evaluated depending on the sport in either a multiple baseline or a reversal design. The behavioral dimensions selected were blocking in football; backward walkovers, front hand springs, and reverse kips in gymnastics; and the forehand, backhand, and serve in tennis. Behavioral coaching was immediately effective in increasing the correct execution of complex skills in all three sports. Gains of up to 10 times the baseline performance were achieved in each sport. In football, behavioral coaching resulted in an increase in correct blocking performance from a baseline average of 5% to 51.3%. Gymnasts' performances increased from baseline averages of 2.7% to 52.6% across the three skills. In tennis, standard coaching produced an average of 6% correct performance which increased dramatically under behavioral coaching to 57% across the three strokes. The success of the behavioral coaching package used here suggests that a technology of behavior may offer additional and complementary strategies to the acquisition of motor skills in the natural environment.     

Suprathreshold binocular interactions for grating patterns

Binocular interactions of suprathreshold grating patterns have been investigated using a reaction time measure of contrast detection. Simple reaction times were determined for monocular and binocular viewing conditions over a contrast range from .63 to near threshold. The results from all subjects showed binocular summation for contrast levels near threshold, but there was considerable variation across subjects for contrast levels above threshold. Some subjects showed summation over the entire contrast range, but other subjects showed either binocular inhibition or binocular facilitation for some range of contrast levels. The pattern of binocular interaction for a given subject was consistent for several spatial frequencies. The differences in types of interaction between subjects, the variation in magnitude of binocular interaction with contrast level for each subject, and the data from experiments involving stimulation of noncorresponding retinal areas show that the binocular interactions found for suprathreshold stimuli cannot be accounted for on the basis of probability, and must, therefore, result from physiological interactions between the two eyes. These interactions have been investigated further under conditions of (1) induced fixation disparity, (2) horizontal gratings, and (3) orthogonally oriented gratings.     

Classes,collections, and distinctive features: Alternative strategies for solving inclusion problems

This study analyzed the strategies that children ages 5 through 8 years used on two modified versions of Inhelder and Piaget's (The early growth of logic in the child. New York: Norton, 1964) class inclusion task. In two experiments, children were tested on Wilkinson's (Cognitive Psychology, 1976, 8, 64–85) “percept” inclusion task in which distinctive features marked both supraordinate and subclasses. It was hypothesized that children who fail standard Piagetian inclusion tasks succeed on the “percept” task by counting and comparing mutually exclusive features rather than using features as markers for classes and subclasses. The hypothesis was supported by children's performances on “percept” tasks in which solutions based on feature counting conflicted with solutions based on consideration of class inclusion relations. In two other experiments, children answered part-whole and part-part comparison questions in which both terms were described as classes and/or subclasses, or in which one of the two terms was described as a collection (e.g., a bunch of grapes). These experiments contrasted Markman and Seibert's (Cognitive Psychology, 1976, 8, 561–577) “organization” hypothesis that the greater psychological integrity of collections facilitates reasoning on part-whole comparison problems with the hypothesis that the faciltative effect results from the “large number” connotation of collective nouns. Results on collection problems in which parts were described as collections supported the “large number” hypothesis. Results were discussed in terms of their implications for Piaget's theory.     

Apparatus for collecting voice chronography data

The conversion of speech into on-off pulse patteras representing talk spurts and pauses is a major tool used by psychologists in analyzing interactive communications behavior. We describe a conversion method and a means for interfacing its output with a computer, which allows the collection of large amounts of speech data from one or more sources. The major improvement over prior art is the ability to reject cross talk between neighbor speakers while permitting the detection of simultaneous speech. In the evaluation of the performance of the apparatus, no errors were detected for single-party speaking. Infrequent small errors occurred in the detection and duration of talk spurts and pauses during two- and three-party speaking, but these would probably be acceptable in most applications.