Individual differences in speed of retrieval from semantic memory

In the first of two experiments, the stimulus items consisted of category names followed by a single letter (e.g., fruit-P). The subjects (half introverted, half extraverted) were required to respond as quickly as possible with a member of the specified category starting with the letter. Extraverts responded significantly faster than introverts, and more so when the most likely response was of low frequency than when it was of high frequency. In the second experiment, subjects were assigned to one of four groups representing the four combinations of high and low Extraversion and high and low General Activation. The speed-of-recall task from the first experiment was used on some trials; on the remaining trials, a speed-of-recognition task was used. Extraverts had greater response speed than introverts for recall, but not for recognition. That finding, plus interactions between Extraversion and General Activation, suggested an interpretation of the results in terms of the Yerkes-Dodson Law.     

The development of children's problem solving in a gears task: A problem space perspective

I examined two contexts of development in children's problem solving: (1) the macro-context of different age cohorts (8–9 vs 11–12 years of age); and (2) the micro-context of an approximately one-hour experimental session. Twenty subjects (even divided across sexes and these two age groups) were individually presented a collection of variously sized gears, a board onto which these gears could be easily attached and rotated, and a knob. Each subject was asked to find all solutions, in which two marked gears were turning the same way, and to represent these solutions graphically. Subjects applied four different problem spaces to the task: the Euclidean, the Kinematic, the Dynamic, and the Topological. The Arithmetic Modifier could be applied to any of these problem spaces, resulting in a numerical characterization of the gear constructions and/or production strategies. The 11–12's tended to shift problem spaces adaptively; the 8–9's seldom did so. Analysis of the pathways of transition between the problem spaces revealed a complex picture of partial or complete incorporation, and substitution.     

A meta-analysis and conceptual critique of research on role ambiguity and role conflict in work settings

Although role ambiguity and role conflict have been studied extensively in the organizational sciences, there remain numerous empirical discrepancies among the reported research results. Consequently, disagreement exists as to what can be concluded about the role ambiguity and role conflict research. Coupled with this empirical impasse has been a persistent and relatively singular approach to conceptually studying role ambiguity and role conflict. In response to this empirical and conceptual situation, a meta-analysis and a conceptual reevaluation of the role ambiguity and role conflict research were performed. Using the Hunter, Schmidt, and Jackson (1982, Meta-analysis: Cumulating research findings across studies, Beverly Hills, CA: Sage) meta-analysis procedures, this study analyzed 29 correlates of role ambiguity and role conflict. These correlates include ten organizational context variables, five individual characteristics, ten affective reactions, and four behavioral reactions. Meta-analysis procedures were used to measure the strength and consistency of the relationship found between each of the 29 correlates and role ambiguity and role conflict. Meta-analysis was also used to determine where moderator variables should play a critical part in future role ambiguity and role conflict research. Based on the results of the meta-analysis, several empirical summaries and conclusions are presented. Along with these, several conceptual observations and reconceptualizing suggestions are offered. It is concluded that while a great deal is known about role ambiguity and role conflict in the organizational sciences much remains to be learned.     

Stimulus selection with duration as a relevant cue

To date, research has not explicitly examined how duration competes with other stimulus dimensions for control over responding. The present study investigated some familiar selective mechanisms of stimulus control over key pecking in pigeons, with duration and line tilt as discriminative stimuli in successive discrimination procedures. Specifically, pigeon's key pecking was reinforced with food or extinguished following compound stimuli comprising one of two line orientation stimuli presented for one of two different durations. Traditional experimental designs explored stimulus additivity, overshadowing, blocking, and learned irrelevance. Although stimulus additivity was observed, control by duration was masked by line tilt in extinction testing that followed facilitated acquisition with redundant, relevant cues. In addition, although prior training with duration relevant partially blocked subsequent acquisition of control by line tilt when both stimulus dimensions were relevant, there was a tendency for control by duration to decrease with continued compound training. It was suggested that the greater time required to distinguish duration on a trial—compared to more commonly studied stimulus dimensions, which can be distinguished almost immediately—puts duration at a competitive disadvantage in situations where other relevant dimensions are also available.     

Emotional Responses to APO E Genotype Disclosure for Alzheimer Disease

The purpose of our study is to assess the emotional responses to disclosing APO E genotype to asymptomatic older adults at increased risk for Alzheimer disease (AD). This is a longitudinal cohort study of volunteer subjects who were aged 50 years or over, asymptomatic for (AD), had a family history of AD, passed a psychological assessment, and participated in pre- and post-test genetic counseling and three follow-up visits over 10 months. We analyzed responses by three emotional constructs: depressed, worried, and relieved. Three hundred and twenty-eight subjects were screened, 76 received their APO E genotype. When emotional responses occurred it was immediate, between baseline and the 1 month follow-up. Emotional reactions did not change significantly past 1 month. Our results suggest that for emotionally stable persons, disclosing results of their APO E genotype, high risk subjects did not report more depression or worry and low risk subjects felt relieved by knowing the results. Future studies should evaluate the risks of disclosure to family members involved in the diagnostic work-up of a relative and include subjects from a broader range of emotional stability and socioeconomic background.     

A Review Of Geraldine Jonçich's The Sane Positivist: A Biography Of Edward L. Thorndike

This book review, unfinished at the author's death, examines in historical context Thorndike's law of effect, his Animal Intelligence monograph of 1898, and related works on learning and behavior.     

Thorndike's Puzzle Boxes And The Origins Of The Experimental Analysis Of Behavior

The year of Thorndike's dissertation on animal intelligence, 1898, may mark the beginning of the field that eventually became known as the experimental analysis of behavior. The dissertation began a major shift in thinking about animal and human learning, provided important methodological innovations, and carried the seeds of later research and theory, particularly by B. F. Skinner. Although Thorndike was an associationist in 1898, the dissertation began the systematic search for fundamental behavioral processes, and laid the foundation for an empirical science of behavior.     

Edward L. Thorndike: the selectionist connectionist

From the very outset of his work, Thorndike allied himself with the Darwinian proposition that complex phenomena can arise as the cumulative effects of a selection process, here the process envisioned by the law of effect. Thorndike's selectionist approach, when combined with his connectionism, laid the foundation for a synthesis of behavior analysis and neuroscience.