Processing capacity defined by relational complexity: implications for comparative, developmental, and cognitive psychology

Working memory limits are best defined in terms of the complexity of the relations that can be processed in parallel. Complexity is defined as the number of related dimensions or sources of variation. A binary relation has one argument and one source of variation; its argument can be instantiated in only one way at a time. A binary relation has two arguments, two sources of variation, and two instantiations, and so on. Dimensionality is related to the number of chunks, because both attributes on dimensions and chunks are independent units of information of arbitrary size. Studies of working memory limits suggest that there is a soft limit corresponding to the parallel processing of one quaternary relation. More complex concepts are processed by "segmentation" or "conceptual chunking." In segmentation, tasks are broken into components that do not exceed processing capacity and can be processed serially. In conceptual chunking, representations are "collapsed" to reduce their dimensionality and hence their processing load, but at the cost of making some relational information inaccessible. Neural net models of relational representations show that relations with more arguments have a higher computational cost that coincides with experimental findings on higher processing loads in humans. Relational complexity is related to processing load in reasoning and sentence comprehension and can distinguish between the capacities of higher species. The complexity of relations processed by children increases with age. Implications for neural net models and theories of cognition and cognitive development are discussed.     

Reaction time to letter name or letter case

Subjects were shown two letters from the set BDGbdg. In one condition, subjects were required to decide whether or not the letters had the same name. In the other condition, subjects decided whether or not the two letters were presented in the same case. Reaction times were always faster when the two letters on a given trial were physically identical. However, there was no difference in the speed of a name match or a case match when the two letters were not physically identical. Since subjects could have based a case match on the presence or absence of a single feature — a protruding vertical line — it was concluded that subjects are not able to selectively attend to a single visual feature in order to identify a letter. Rather, a subject analyzes several features in parallel in order to arrive at a simultaneous decision about a letter's name or case.     

Scientific Realism: Old and New Problems

Scientific realism is a doctrine that was both in and out of fashion several times during the twentieth century. I begin by noting three presuppositions of a succinct characterization of scientific realism offered initially by the foremost critic in the latter part of the century, Bas van Fraassen. The first presupposition is that there is a fundamental distinction to be made between what is “empirical” and what is “theoretical”. The second presupposition is that a genuine scientific realism is committed to their being “a literally true story of what the world is like”. The third presupposition is that there are methods for justifying a belief in the empirical adequacy of a theory which do not also suffice to justify beliefs in its literal truth. Each of these presuppositions raises a number of problems, some of which are quite old and others rather newer. In each case, I briefly review some of the old problems and then elaborate the newer problems.     

Characteristics of Children and Adolescents Admitted to a Residential Treatment Center

Studies of youths in residential treatment that utilize systematic assessments and validated measures are rare. We examined psychopathology, family characteristics, occurrence of physical or sexual abuse, types of aggressive behavior, hyperactive/impulsive behavior, medical and neurological problems, and self-reported drug and alcohol use in 397 youth who were assessed using reliable measures and consecutively treated in a residential treatment center. Results indicate high rates of internalizing and externalizing psychopathology, aggressive behavior, and consistent gender differences, with girls having higher levels of internalizing and externalizing psychopathology and aggressive behavior. The sample was characterized by high rates of medical problems including asthma, seizures, and obesity, as well as evidence of extensive family dysfunction, including high rates of parental alcohol use, violence, and physical or sexual abuse. Residential treatment needs to progress beyond the one size fits all approach and develop more specific and empirically proven treatments for the specific needs of this population.     

The forgotten ones? The validity of consideration and initiating structure in leadership research

This study provided a meta-analysis of the relationship of the Ohio State leadership behaviors--Consideration and Initiating Structure--with leadership. Overall, 163 independent correlations for Consideration and 159 correlations for Initiating Structure were analyzed. Results revealed that both Consideration (.48) and Initiating Structure (.29) have moderately strong, nonzero relations with leadership outcomes. Consideration was more strongly related to follower satisfaction (leader satisfaction, job satisfaction), motivation, and leader effectiveness, and Initiating Structure was slightly more strongly related to leader job performance and group-organization performance. Validities did vary by leadership measure, but in most cases validities generalized regardless of the measure used. Overall, the results provide important support for the validity of Initiating Structure and Consideration in leadership research.     

Hospital restructuring and nursing staff well-being: The role of perceived hospital and union support

Abstract

This research examined the effects of perceived hospital and union support on work satisfaction and psychological well-being of nursing staff during a period of hospital restructuring and downsizing. Data were collected from 1363 hospital-based nurses using anonymous questionnaires. Respondents reported receiving moderate levels of both hospital and union support during this period. However nursing staff reporting higher levels of perceived hospital support indicated greater job satisfaction, more job security, lower levels of psychological burnout and fewer psychosomatic symptoms, controlling for personal and work situation factors and extent of restructuring and downsizing initiatives. Implications for organizational management during downsizing and reorganization are drawn.