Knowledge that Transforms

Given the task of diagnosing the source of a patient's allergic reaction, college students judged the causal efficacy of common (X) and distinctive (A and B) elements of compound stimuli: AX and BX. As the differential correlation of AX and BX with the occurrence and nonoccurrence of the allergic reaction rose from .00 to 1.00, ratings of the distinctive A and B elements diverged; most importantly, ratings of the common X element fell. These causal judgments of humans closely parallel the conditioned responses of animals in associative learning studies, and clearly disclose that stimuli compete with one another for control over behavior.

It is now well known that the retention of newly-acquired information can be modulated by drugs or hormones administered shortly following training. It is generally thought that such treatments influence retention by modifying processes underlying the storage of information. The fact that susceptibility to posttraining memory modulation is seen in many species, including bees, fish, birds, and mammals, argues that some common time-dependent memory storage processes have been conserved in evolution. Recent research findings have provided strong support for the view that such susceptibility to posttraining influences provides opportunity for modulation of memory storage by endogenous neurohormonal systems. In rats and mice, posttraining administration of hormones such as epinephrine that are normally released by training experiences enhances subsequent retention. Comparable effects are found with posttraining administration of opiate receptor antagonists such as naloxone. Findings of recent experiments indicate that these treatments affect memory by influencing the release of norepinephrine within the amygdaloid complex. The endogenous regulation of memory storage appears to involve interaction of neurohormones and transmitters in activating brain systems involved in memory storage.

Recent experiments indicate that peripheral glucose administration enhances memory in rodents and humans. This study examined the effects of glucose on memory and nonmemory measures of neuropsychological functioning in elderly humans. Healthy older adults were given a series of neuropsychological tests after drinking glucose- or saccharin-flavored lemonade. A repeated measures design using counter-balanced beverages and tests was used. Glucose enhanced performance on declarative memory tests but not on short-term or nonmemory neuropsychological measures. Glucose tolerance predicted performance on declarative memory tasks but not on other measures.

James looked for general principles in terms of which reasoning could be understood, and, in doing so, he sought to understand what it was about human beings that made them human.

Unconventional techniques considered by the United States Army for enhancing human performance were reviewed during a two-year study by a committee of the National Research Council. Little or no scientific evidence was found to support the effectiveness of several, including neurolinguistic programming in interpersonal influence and such paranormal techniques as remote viewing and psychokinesis. Mixed results were seen to characterize other techniques, for example, group-cohesion procedures. Further study was suggested for a few, including mental practice of motor skills. Guidelines requested of the committee for future army evaluation of enhancement techniques stressed the need for, and the conduct of, both laboratory and field research. The committee recommended further consideration of mainstream research in the behavioral sciences as a basis for effective performance enhancements.

Research on juror comprehension is reviewed with special attention to recent studies comparing types of definitions of three levels of the standard of proof (preponderance of the evidence, clear and convincing evidence, and beyond a reasonable doubt). Quantified definitions, (in which the standard of proof was expressed in probability terms, and combined quantified and legal definitions had their intended effect; verdicts favoring the plaintiffs decreased in number as the standard of proof became stricter. Nonquantified definitions did not achieve their intended effect on verdicts. The greater effectiveness of quantified definitions in communicating certainty levels precisely and concisely is attributed to the implicit context provided by their positions on an interval scale with known endpoints (i.e., 0-100%).

Previous research on transfer in problem-solving has primarily been concerned with the transfer of a specific solution procedure from a source problem to an analogous target problem. This paper considers whether transfer may also occur at a more general level of description, namely that responsible for specifying a common representation (e.g., a matrix) for two problems. The results of an experiment showed convincingly that representational transfer can occur in the absence of a common solution procedure for the problems. This result opens up a new area of research on transfer in problem solving.

Although there has been a tremendous outpouring of research on the consequences of children's television viewing, little is known about the causes of individual differences in television viewing, which is one of the major activities of childhood. We present results from the first parent-offspring and sibling adoption analyses of individual differences in time spent watching television in early childhood, and we consider IQ and temperament as possible mechanisms of genetic influence. The sample consisted of over 220 adopted children studied at 3, 4, and 5 years of age, the complete sample of probands from the Colorado Adoption Project. Also assessed are the adoptees’ biological and adoptive parents, matched nonadoptive families, and younger adoptive and nonadoptive siblings. Both the parent-offspring and sibling adoption designs yielded evidence for significant genetic influence on individual differences in children's television viewing. Neither IQ nor temperament appear to be responsible for this genetic influence.

Cultural adjustment involves both acculturation and assimilation. In the present study cultural adjustment is conceptualized similarly to Mendoza and Martinez's Model of Acculturation (1981). It is suggested that cultural adjustment is a process of multiple interacting factors distinguished by different behavioral, cognitive, affective and demographic attributes and by different levels, varying from cultural assimilation to cultural transmutation. A total of 159 students, 92 international and 67 U.S. students, responded to mailed questionnaires. The main findings suggest that cultural adjustment is simultaneously affected by employment level, language spoken at home, having both American and native friends, internal decision making, and work value. The study supports a native-extinction, host-association model of cultural adjustment.