Dividing attention within and between hemispheres: testing a multiple resources approach to limited-capacity information processing

Two experiments tested the limiting case of a multiple resources approach to resource allocation in information processing. In this framework, the left and right hemispheres are assumed to have separate, limited-capacity pools of undifferentiated resources that are not mutually accessible, so that tasks can overlap in their demand for these resources either completely, partially, or not at all. We tested all three degrees of overlap in demand for left hemisphere supplies, using dual-task methodology in which subjects were induced to pay different amounts of attention to each task. Experiment 1 compared complete and partial overlap by combining a verbal memory load with a task in which subjects named nonsense syllables briefly presented to either the left or right visual field (LVF and RVF, respectively). Experiment 2 compared complete versus no overlap by using the same verbal memory load combined with a laterally presented same-different judgment task that did not require a spoken response. Decrements from single-task performance were always more severe when the visual field task stimulus was presented to the RVF. Further, subjects in Experiment 1 were able to trade performance between tasks on both LVF and RVF trials because there was always at least some overlap in left hemisphere demand. In Experiment 2, performance trade-offs were observed on RVF (complete overlap) trials, but not on LVF trials, where no overlap in demand existed. These results contradict a single-capacity model, but they support the idea that the hemispheres' resource supplies are independent and have implications for both cerebral specialization and divided attention issues.     

The problem of relapse in stuttering: Some thoughts on what might cause it and how to deal with it

Bloodstein recently wrote that “the most vital part of science is not accurate measurement or the insistence on empiricism. It is an attitude of inquiry into the how and why of things” [Bloodstein, O. Foreword. In: Maintenance of Fluency (E. Boberg ed.). New York: Elsevier, 1981, p. vii]. In the paper below, I present some unsubstantiated and no doubt controversial thoughts on the how and why of relapse in stuttering. The overall thrust of these thoughts is that stutterers have different propensities to stutter because of the inherent variability in their speech production systems. For this reason, for therapy to have long-range success, stutterers must learn to accept and deal with the inherent variability in their speech production mechanisms.     

Constraints on strategy construction in a speeded discrimination task

In three experiments, subjects reported the identity of a word (above or below) that appeared above or below a fixation point. On some trials, a cue presented 100, 200, 400, 600, 800, or 1,000 msec before the word indicated the relation between position and identity (i.e., whether the dimensions were compatible, e.g., above/above and below/below, or conflicted, e.g., above/below and below/above). On the other trials, the cue was withheld (Experiment 2) or it bore no information about the relation between dimensions (Experiment 1 and 3). In each experiment, the cue reduced reaction time below the level of no-cue or neutral-cue controls, indicating strategic use of the relation between dimensions. Experiments 1 and 2 manipulated the number of potential cues that could occur in a block. A stronger cuing effect was found when one cue could occur (Experiment 2) than when two cues could occur (Experiment 1). Experiment 3 manipulated practice; it revealed that with practice the cuing effect reached asymptote at shorter delays. The asymptote itself did not change. Experiment 4 showed that cue-delay effects were independent of warning interval (warning interval and cue delay confounded in Experiment 1, 2, and 3). The experiments demonstrate construction and utilization of strategies; they show that construction is sensitive to constraints imposed by the subject's goals and abilities and by the structure of the task environment.     

Influence of a televised model's vocalization pattern on infants

To assess the influence of a televised model's vocalizations on the vocal patterns of infant viewers, 32 infants at 6 months of age were presented either a televised adult model repeating a novel phoneme pattern (/ba/ba/ba/ba) or a control televised presentation of adult conversation selected from typical daytime programming. Sequential analyses of infant vocalizations revealed that infants exposed to the televised model altered their vocalization pattern, as indicated by a significant increase over base line levels in their production of a patterned series of discrete vocalizations. Infants exposed to the televised conversation showned no increase in this pattern of vocalization, and none of the infants in the study produced the novel phoneme (/ba/). The results indicate that televised presentation of discrete, repeated vocalizations can have an influence on the vocalization pattern of infants. The potential role of television in infant development is discussed.     

Sex differences in causal attributions for success and failure in real and hypothetical sport settings

In Experiment 1, a 48-item attribution questionnaire was administered to 22 members of the men's and women's varsity basketball teams, respectively, after an intrasquad scrimmage. In Experiment 2, the same questionnaire was administered to a random sample of 54 undergraduates who were told to imagine a hypothetical scrimmage. Losing male athletes rated internal characteristics as less important in determining the outcome than did losing females. Winning females rated the opponent's characteristics as less important in determining the outcome than did winning males. Hypothetical female winners rated the opponent's characteristics as more important than did hypothetical male winners. The lack of correspondence in the outcomes of the two experiments and possible methodological shortcomings in the attribution literature are discussed.The two authors participated equally in the preparation of this article. Portions were presented at the First Annual Meeting of the North American Society for the Sociology of Sport, Denver, October 1980. We sincerely thank Coach Margaret Sisson and Coach Thomas Prechtl of the varsity women's and men's basketball teams, respectively, of the State University of New York — College at Fredonia, for their assistance in carrying out this project. We also thank the editors of this issue for their helpful criticisms of earlier versions of this article.     

Facilitation and helplessness: The interaction of perceived difficulty and importance of a task

Experimentally induced failure sometimes produces helplessness and sometimes facilitation on subsequent tasks. A model which accounts for this in terms of variations in perceived task difficulty and importance and variations in the cost of effort is proposed. Predictions from the model were confirmed in two experiments using the finger shuttlebox. When subjects expected the test task to be easy, importance of test outcome did not affect performance. However, when they expected the test task to be difficult, low outcome importance led to debilitation, and high importance to facilitation. If, in this condition, subjects experienced initial failure on the task perceived as difficult and important, helplessness rather than facilitation was observed. The model proposed may account for some of the conflicting results obtained in laboratory studies of human helplessness.     

The rapid-smoking technique: Subject characteristics and treatment outcome

There is a lack of consistency in findings regarding subject (S) characteristics and the effects of smoking-control programmes. Research workers appear to assume that abstinence and reduction in smoking rate are merely different points in the same continuum, and therefore seek to correlate S variables with percentage reductions in smoking rate. It is argued that abstinence and reduced smoking are more appropriately viewed as potentially discrete outcomes. Conceptualizing outcome in this manner, a discriminant function analysis was employed to determine whether it is possible to differentiate between Ss who do, or do not, abstain following participation in a treatment programme involving rapid-smoking. It was found that it is possible to discriminate between the two groups of Ss. Advantages deriving from this approach to the investigation of S characteristics and treatment outcome are discussed.