Discrimination Reversal Conditioning of an Eyeblink Response is Impaired by NMDA Receptor Blockade

In the present study we examined the effects of the specific NMDA receptor antagonist CPP on discrimination reversal learning in rabbits. We report two primary findings. First, the institution of NMDA receptor blockade had no effect on a learned discrimination. Second, after stimulus reversal, CPP treatment impaired acquisition of the discrimination reversal. This impairment manifested itself early in training as a retardation in acquisition of a CR to the new CS+ and late in training as an inability to suppress responsiveness to the new CS-. Given the comparability of the present results with previously published results for phenytoin-treated rabbits, we suggest that the effects of phenytoin on learning in this paradigm is at least in part mediated by its effects on NMDA receptors. We further suggest that these findings emphasize the need to better define the role of NMDA receptor activation and hippocampally-mediated circuits in a variety of associative learning paradigms.     

The Relationship Between Attitudinal Ambivalence and Desire to Quit Smoking Among College Smokers1

Growing evidence shows that attitudes can exist on a bivariate rather than a bipolar plane. This conceptualization provides a more dynamic approach to studying how attitudinal ambivalence (i. e., evaluating an attitude object as both positive and negative) affects smoking‐related behaviors. Based on a sample of 157 college smokers, we obtained preliminary validational support for a smoking‐specific felt attitudinal ambivalence scale. Felt attitudinal ambivalence correlated positively with potential for ambivalence, negative attitudes, and negative as well as positive outcome expectancies related to smoking. Smokers who felt more ambivalent reported a greater desire to quit and were more likely to be contemplators, as defined by the transtheoretical model of behavioral change. In multivariate analyses, felt ambivalence toward smoking predicted desire to quit after controlling for positive and negative attitudes and negative smoking consequences. These results provide promising support for the smoking‐specific felt‐ambivalence scale, and suggest that attitudinal ambivalence should be investigated further as a motivational mechanism to affect smoking cessation.     

Response to Michael Sells

In an era when lies and misrepresentations about historical events easily become firmly rooted, Michael Sells's discussion illustrates the importance of careful historical research as a moral enterprise. In addition to the skills of the historian, however, there is also room in this enterprise for those of the ethicist. In particular, I warn against confusing the truth or falsity of claims about one narrow historical period with larger questions about the moral meaning and significance of those claims. Illustrating this, I argue one cannot assess the legitimacy of competing nationhood claims solely on the basis of the deeds of specific actors. Nor should the actions of a single individual like the Grand Mufti of Jerusalem be converted into a totalizing claim about the rights of the Palestinian people.     

THE PRESIDENT'S COUNCIL ON BIOETHICS—REQUIESCAT IN PACE

In mid‐June 2009, the Obama administration dissolved the President's Council on Bioethics (PCBE), a group established by President George W. Bush in August 2001 and whose nearly eight‐year life was marked from beginning to end by controversy. While some will regret the PCBE's passing, others will regard the Council as a failed experiment in doing public bioethics.     

The nonequivalence of behavioral and mathematical equivalence.

Sidman and his colleagues derived behavioral tests for stimulus equivalence from the axiom in logic and mathematics that defines a relation of equivalence. The analogy has generated abundant research in which match-to-sample methods have been used almost exclusively to study interesting and complex stimulus control phenomena. It has also stimulated considerable discussion regarding interpretation of the analogy and speculation as to its validity and generality. This article reexamines the Sidman stimulus equivalence analogy in the context of a broader consideration of the mathematical axiom than was included in the original presentation of the analogy and some of the data that have accumulated in the interim. We propose that (a) mathematical and behavioral examples of equivalence relations differ substantially, (b) terminology is being used in ways that can lead to erroneous conclusions about the nature of the stimulus control that develops in stimulus equivalence experiments, and (c) complete analyses of equivalence and other types of stimulus-stimulus relations require more than a simple invocation of the analogy. Implications of our analysis for resolving current issues and prompting new research are discussed.     

Predictors of adolescent female decision making regarding contraceptive usage.

The relationship of cognitive capacity, cognitive egocentrism, and experience factors to decision making in a contraceptive usage problem was examined. Fifty sexually active, unmarried females, ages 14-19, served as subjects. Using correlational, regression, and canonical correlational analyses, cognitive capacity and cognitive egocentrism variables, not experience with contraceptives, were found to be significantly related to, and predictive of, five of seven decision-making variables. Forty-one percent of the variance was accounted for in predicting the canonical decision-making variable. The implications of these results for future research are discussed.     

Clarification of the dual task dilemma: Lateralized effects for perfunctory and purposeful tasks in left- and right-handed males

The hypothesis that behavioral asymmetries with the dual task paradigm represent manual dominance was investigated with right- and left-handed males performing verbal and spatial tasks ordered by complexity. Lateralization was assessed for nonideational (perfunctory) and ideational (purposeful) components of tasks with multivariate and ANCOVA procedures. The outcomes of prerequisite tests showed the assumptions for conducting ANCOVA procedures were not satisfied with different handedness groups in the same design. However, results of the multivariate analyses suggest lateralized effects are more likely to represent the cognitive task when interference is high and may represent manual dominance when interference is low.