THE TRAINING AND GENERALIZATION OF A CONVERSATIONAL SPEECH FORM IN NONVERBAL RETARDATES1

Differential reinforcement and imitation were used with two retarded children to train three sequential verbal responses associated with the display of a picture and questions related to that picture. Each response consisted of a three-word chain in sentence form; combined with verbal responses from the experimenter, this trained sequence formed a short conversational unit. Three experimenters measured the use of each sentence in settings different than the one in which training took place, and with pictures different than those used during training. Two types of generalization sessions were used: (1) General sessions, during which 10 pictures never used during training were displayed to the subject with reinforcement delivered on a noncontingent basis, and (2) Intermixed sessions, during which 10 pictures never used during training were displayed to the subject, but a picture having received training was also displayed, and correct responses to this picture were reinforced on a variable schedule. Both subjects learned the sentences being trained. However, little generalization was evident from this training when all experimenters conducted General probe sessions. Generalization occurred with one experimenter only after that experimenter conducted Intermixed probe sessions. Generalization to a third experimenter was then observed (i.e., after the first two experimenters had conducted Intermixed probe sessions) without the use of Intermixed probe sessions by this third experimenter.     

Foreground and background in dynamic spatial orientation

The dependency of visually induced self-motion sensation upon the density of moving contrasts as well as upon additional stationary contrasts in the foreground or background was investigated. Using two different optokinetic stimuli, a disk rotating in the frontoparallel plane, and the projection of horizontally moving stripes onto a cylindrical screen, it was found that: (1) visually induced self-motion depends upon the density of moving contrasts randomly distributed within the visual field and, with a single contrast area of 1/4 %, is saturated when about 30% of the visual field is moving; (2) additional stationary contrasts inhibit visually induced serf-motion, proportional to their density; and (3) the location in depth of the stationary contrasts has a significant effect upon this inhibition. Their effect is considerable when located in the background of the moving stimuli but weak when appearing in the foreground. It is concluded that dynamic visual spatial orientation relies mainly on information from the seen periphery, both retinal and depth.     

Range estimates of distant visual stimuli

Os made magnitude estimations of the range of visual targets located at physical distances from a few hundred yards or less to more than 5 miles. The targets were at different elevations in different experiments so that O’s gaze varied from 0 to 90 deg. The targets were presented against the empty sky or against water. The Os were stationary in most experiments, but were in motion in one. Results show that the psychophysical functions are power functions whose exponents range from ca. 1.25 to 0.8, depending on the angle of the target above the horizontal. Background texture or O motion had no effect.     

Individual commitment to risky and conservative choices as a determinant of shifts in group decisions1

The consistently positive relationship between initial riskiness and perceived influence obtained in past work led us to speculate that (1) the deliberative effort involved in making a choice increases with its riskiness, as a result (2) individuals who select a risky course of action will be more committed to their choice than conservative individuals, and (3) the former will be more influential in group decisions. The following support was obtained for these conjectures When individuals had to select a reaction time interval to beat, those who were risky, that is, who selected a short interval, were more confident in having chosen wisely, were less likely to feel they might change their choice given the opportunity, and took longer to make their choice than those who were conservative, that is, who selected a long interval The first two of these measures were assumed to reflect commitment to the choice, and the third was taken as a rough indication of the amount of effort involved in choosing A group decision was also made regarding the reaction time interval It tended to be riskier than that preferred by the average individual prior to the decision if the riskiest member was more committed and/or expended more effort in choosing than his partners, on the other hand, it tended to be more conservative than the average prior preference if the most conservative member was more committed and or expended more effort     

Brightness of paired photic pulses with pulse duration and separation varied

The brightness of pairs of photic pulses, differing in pulse duration and pulse separation. was measured. The data were in general agreement with the neurophysiological model of Bishop and Clare. Pulse duration appeared to have little systematic influence on the shape of the curves. Time between onset of the first and second pulse appeared to be a prime factor determining the receptivity of the cortex to the second pulse. The two pulses were seen as single below about .03 sec separation. The second pulse was always judged brighter than the first.     

Additional techniques for producing multiple-schedule control in children,

The subjects in these experiments were 132 children, varying in age from 4 to 7 years. These experiments were designed to assess the efficacy of various multiple scheduling procedures in producing reliable stimulus control. The schedules studied were multiple fixed-ratio-extinction (mult FR EXT); multiple differential-reinforcement-of-other-behavior-fixed-ratio (mult DRO FR); multiple differential-reinforcement-for-low-rate-fixed-ratio (mult DRL FR); and multiple fixed-interval-fixed-ratio (mult FI FR). In addition other techniques were investigated, such as presenting FR's in blocks; increasing the size of the FR's; attaching a DRL to the FI members; temporarily shifting to new schedules; and adding an external clock to the FI's. These experiments yielded the following results.1.) Strong stimulus control was produced by mult FR EXT, mult DRO FR, and mult DRL FR schedules. Control for mult FR EXT was mediated principally by the individual stimuli, though on occasion it was dependent in part on the change of stimuli. The mult DRO FR was found to be highly useful for those children who had very high initial rates or who were generally uncooperative and unmanageable.2.) Contrary to a previous finding, some subjects were brought under stimulus control by means of mult FI FR schedules without the aid of additional procedures. Most, however, were not. Additional techniques found to augment the development of mult FI FR control included: (1) presenting FR's in blocks; (2) increasing the size of the FR's; (3) attaching a DRL to the FI component for a time and later removing it; and (4) shifting to a mult DRL FR, developing control, and then returning to the original mult FI FR.3.) Addition of an external clock to the FI components of the mult FI FR had several effects. Strongest control, including well-developed acceleratory patterns during the FI's, was developed in those subjects who had first been shifted from a regular mult FI FR to a mult FR EXT, brought under control, and then returned to the mult FI FR with the clock added. The added clock also produced strong control if it was present when the subject was first begun on a mult FI FR schedule. In some cases, the addition of the clock produced control in subjects who had not been controlled previously by the regular mult FI FR, but these were always subjects who had high rates. The addition of the clock first lowered the rate, then produced control.     

Engineering Codes of Ethics and the Duty to Set a Moral Precedent

Each of the major engineering societies has its own code of ethics. Seven “common core” clauses and several code-specific clauses can be identified. The paper articulates objections to and rationales for two clauses that raise controversy: do engineers have a duty (a) to provide pro bono services and/or speak out on major issues, and (b) to associate only with reputable individuals and organizations? This latter “association clause” can be justified by the “proclamative principle,” an alternative to Kant’s universalizability requirement. At the heart of engineering codes of ethics, and implicit in what it is to be a moral agent, the “proclamative principle” asserts that one’s life should proclaim one’s moral stances (one’s values, principles, perceptions, etc.). More specifically, it directs engineers to strive to insure that their actions, thoughts, and relationships be fit to offer to their communities as part of the body of moral precedents for how to be an engineer. Understanding codes of ethics as reflections of this principle casts light both on how to apply the codes and on the distinction between private and professional morality.