Anisomycin impairs long-term working memory in a delayed alternation task

A long-term temporal component of working memory of rats trained on the radial maze has been shown to be susceptible to disruption by the protein synthesis inhibitor, anisomycin. It is not clear whether protein synthesis played a role in working memory because accurate performance on the radial maze required the storage of a large amount of information, or because the information was to be held in store for relatively long periods of time. This experiment tested these hypotheses by assessing the effect of anisomycin on choice accuracy in a comparatively simple spatial delayed alternation task. Results indicate that under the present training conditions, protein involvement in working memory is related more to the length of the retention interval than to the amount of information retained.     

First, do no harm

Case vignette: sharing unanticipated genetic information. The Questor family has experienced an unusual number of malignancies in the past two generations and has been advised by an oncologist that the p53 oncogene known as Li-Fraumeni Syndrome may be present in the family genome. The option of predictive genetic testing has been raised and several branches of the family have chosen to undergo screening to determine whether they are at risk for cancer because of the gene. Roger and Liz Questor have arranged for screening of themselves and their three children, ages 12, 10, and 7. The couple has, by all appearances, been happily married for 14 years. None of the family members are found to carry the oncogene; however, the geneticist conducting the analyses has made an interesting incidental discovery. The 10-year-old child is not the biological progeny of Roger Questor. Although the 12-and 7-year-olds are clearly the biological children of the couple, it is evident that the 10-year-old born to Liz Questor was fathered by a person other than Roger. What are the ethical obligations of the geneticist with respect to any sharing or disclosure of the information that has been discovered incidentally? What course of action, if any, do you recommend?     

Spontaneous startle activity in newborn infants

Spontaneous startles have been reported to occur most frequently in quiet sleep, less frequently in active sleep and drowse, and relatively nonexistent in the waking states. These findings may be a result of a focus on infants whose prenatal histories reflect a restricted range of the conditions to which normal newborns are exposed. The present study examined the spontaneous startle behavior of 30 newborn infants characterized by high numbers of obstetric complications and by indicators of prenatal malnutrition, but within the range of normal, healthy newborns. In this sample, startles were not limited to the sleep and drowse states. Because individual differences in a number of neonatal behaviors have been related to autonomic nervous system (ANS) functioning, the different pattern of spontaneous startles observed in this sample may be related to the functional integrity of this system.     

The symbolic distance effect for alphabetic order judgements: A subjective report and reaction time analysis

The time needed to decide whether a pair of letters is in the correct alphabetic order varies inversely with alphabetic separation. This is an example of a phenomenon generally found with the comparison of ordered symbols or concepts, called the symbolic distance effect (Moyer and Bayer, 1976). It is argued that when letters are compared, an important determinant of this effect is the degree to which subjects subvocally run-through parts of the alphabet to determine the correctness of the order of a stimulus pair. A trial-by-trial introspection procedure coupled with reaction time measurements is used in the present experiment, in which letter order judgements were made over a range of separations. RTs increased with increasing number of letters in the reported run-through. At small letter separations, run-through occurred more frequently, and this was found to be the basis of the symbolic distance effect. For trials on which no run-through was reported the symbolic distance effect was absent. The data are summarized as a model in which comparisons are made from directly available order information from memory, or with an additional run-through process. The details of the run-through process suggest that groupings learned in childhood are probably involved in the selection of the starting letter for run-through.     

Consequence analysis: Its effects on verbal statements about an environmental project

Typically, citizens lack relevant information concerning possible consequences of proposed environmental projects. Despite federal requirements for citizen participation in decisions about proposed roadway projects, no systematic procedures exist for educating citizens as to the possible consequences of such projects. The effects of a consequence analysis procedure on community residents' verbal statements about the favorability of a proposed roadway project were assessed. The consequence analysis procedure involved asking residents to rate the desirability and magnitude of each of 48 possible consequences of the proposed roadway project. Following the intervention, overall ratings of favorability of the project changed for nine of ten residents. Community residents' ratings of the quality of participants' justifications of their position on the roadway issue provided evidence of generalization to this collateral behavior.     

Vicious-circle behavior in the Y maze

Laboratory rats were given escape training in both arms of a Y maze followed by extinction in one of four conditions: regular (no shock), punished (both arms containing a shock mid-segment), choice, or forced (one arm containing a shock mid-segment, one arm shock free). Subjects in the punished and forced conditions required more extinction trials than those in the regular extinction condition. The choice condition was intermediate and not significantly different from the others. Choice subjects avoided the shock by choosing the safe alley early and consistently during extinction, but some continued to run for many trials without further punishment. It was suggested that the number of punished trials early in extinction is related to persistence of running, and the results were discussed in relation to the Mowrer-Brown and the discrimination hypotheses.