Pre-exposure enhances recovery of conditioned responding after extinction

Four experiments used a within-subjects design with rats to study the effects of preexposure on the restoration of fear responses (freezing) to an extinguished conditioned stimulus (CS). In each experiment, rats were preexposed to one CS (A), but not to another (B), and then were exposed to pairings of each of these CSs with an aversive unconditioned stimulus (US). In each experiment, there was less freezing to A than to B across extinction, showing a latent inhibitory effect of preexposure. There was no differential recovery to A and B following either a US reexposure (Experiment 1) or a delay interval (Experiment 2). However, when a delay interval included US reexposure, there was greater recovery to the preexposed CS, A, than to the nonpreexposed CS, B (Experiments 1, 3, and 4). These results suggest that the effects of US reexposure and delay combine to affect recovery from the depressive effects of CS-alone exposure. The results are consistent with the view that US reexposure produces better mediated conditioning of CSs that are strongly associated with the context. The results may additionally reflect an effect of preexposure on the learning produced by extinction.     

RFID: The Next Serious Threat to Privacy

Radio Frequency Identification, or RFID, is a technology which has been receiving considerable attention as of late. It is a fairly simple technology involving radio wave communication between a microchip and an electronic reader, in which an identification number stored on the chip is transmitted and processed; it can frequently be found in inventory tracking and access control systems. In this paper, we examine the current uses of RFID, as well as identifying potential future uses of the technology, including item-level tagging, human implants and RFID-chipped passports, while discussing the impacts that each of these uses could potentially have on personal privacy. Possible guidelines for RFID’s use, including Fair Information Principles and the RFID Bill of Rights are then presented, as well as technological solutions to personal privacy problems, such as tag killing and blocker tags, as well as simple aluminum foil shields for passports. It is then claimed, though, that guidelines and technological solutions will be ineffective for privacy protection, and that legislation will be necessary to guard against the threats posed by the RFID. Finally, we present what we believe to be the most important legislative points that must be addressed. Vance Lockton has recently completed the M.Sc. program at the University of British Columbia, majoring in Computer Science. Richard S. Rosenberg is a professor emeritus in the Department of Computer Science at the University of British Columbia; the third edition of his book, “The Social Impact of Computers”, was published by Elsevier Academic Press in 2004.     

Some critical episodes in the progress of medical innovation: An Anglo-American perspective

The central concern of this paper is to show that medical innovations have depended heavily on breaking down barriers that have long prevailed in the academic world, in the form of disciplinary boundaries that have coalesced into separate departments; to be specific, some of the biggest breakthroughs for the Life Sciences have come from the realm of the Physical Sciences. The present study is confined mainly to molecular biology and to diagnostic technologies (as well as to the therapeutic technologies that have frequently flowed from them); both owed a great deal to institutional innovations that emerged in the Anglo-American medical research world. Opportunities for transfers of instrumentation and techniques across disciplinary boundaries have been considerably strengthened as medical schools have been located, geographically and organizationally, closer to the universities. The American Medical Centers and the Stanford Program provide many examples. These achieved more than counterparts in the UK like the Cavendish Laboratories at Cambridge, which had pioneered in such fields.     

Web of deceit: A literature review of Munchausen syndrome by proxy

Munchausen syndrome by proxy (MSBP) is a form of child abuse wherein the mother falsifies illness in her child through simulation and/or production of illness, and presents the child for medical care, disclaiming knowledge as to etiology of the problem. From the literature, 117 cases of MSBP were reviewed. The most common presentations of MSBP were bleeding, seizures, central nervous system depression, apnea, diarrhea, vomiting, fever, and rash. Short-term morbidity rate was 100%; long-term morbidity rate was 8%. Mortality rate was 9%. Failure to thrive was associated with MSBP in 14% of cases. All perpetrators of MSBP were the mothers. The origins of this type of aberrant maternal behavior remain abstruse, as do the long-term psychological effects on the child victims. Guidelines for medical, social service, and legal management are provided.     

Scoring of WISC-R comprehension,similarities, and vocabulary responses by experienced and inexperienced judges

Ten judges scored items from the Comprehension, Similarities, and Vocabulary subtests of the WISC-R. Five were inexperienced undergraduates and five were experienced PhDs. Overall, there were no appreciable differences in the percentages of agreement between the two groups.     

Leisure Time Physical Activity and Job Performance

In this study, the dual-task paradigm was used to determine peak attentional demand during the free-throw process. Thirty participants completed 40 free-throw trials. The free throw was the primary task, but participants also verbally responded to a tone administered at one of four probe positions (PP). Repeated measures analysis of variance showed no significant difference in free-throw performance across PPs, indicating participants were able to keep the free throw as the primary task. Repeated measures analysis of response time (RT) showed significant differences, with RT at PP1 (preshot routine) and PP2 (first upward motion of the ball) significantly higher than baseline RT. These results suggest that PP1 requires the greatest attentional demand, followed by PP2.