Beyond belief bias: Reasoning from conceptual structures by mental models manipulation

Mental models constitute an alternative to the rule-based systems in the explanation of human reasoning (Johnson-Laird, 1983). In this paper, we claim that the concept of believability generally used to categorize content and context effects is of little use within a semantic theory. Thus, we propose the use of categories that are directly extracted from subjective relations among concepts within the reasoning problem. We demonstrate that manipulations based on this kind of categorization produce predictable patterns of responses in reasoning problems. We present two experiments to test our predictions, using conditional and syllogistic reasoning problems, and in both cases, we demonstrate the influence of conceptual knowledge not only in natural contexts, but also in experimentally created artificial contexts.     

Detachment and defeasibility in deontic logic

The purpose of the paper is to present a logical framework that allow to formalize a kind of prima facie duties, defeasible conditional duties, indefeasible conditional duties and actual (indefeasible) duties, as well as to show their logical interconnections.     

Compassion: An east‐west comparison

Compassion is an emotion that occupies a central position in Mahāyāna Buddhist philosophy while it is often a neglected subject in contemporary western philosophy. This essay is a comparison between an Eastern view of compassion based upon Mahāyāna Buddhist perspectives and a western view of the same emotion. Certain principles found in Mahāyāna Buddhist philosophy such as the Bodhisattva Ideal, and suffering (dukkha) to name two, are explored for the information they contain about compassion. An essay by Lawrence Blum is taken as representative of a Western view (but not exclusively) and it is analyzed for its shortcomings in light of the Buddhist view. The conclusion briefly describes the value of understanding an eastern view on compassion as a means of filling the void one finds in western medical ethics discourse which focuses so heavily, and redundantly, upon issues such as patient autonomy and paternalism.     

Enhancement of the Post-training Cholinergic Tone Antagonizes the Impairment of Retention Induced by a Nitric Oxide Synthase Inhibitor in Mice

The present experiments examined the role of the central cholinergic system in the memory impairment induced by post-training administration of a nitric oxide synthase (NOS) inhibitor in mice. Male Swiss mice received a one-trial inhibitory avoidance training (0.8 mA, 50 Hz, 1-s footshock) followed immediately by an ip injection of the NOS inhibitor -N^G-nitroarginine methyl ester ( -NAME; 100 mg/kg). Retention (cut-off time, 300 s) was tested 48 h after training. The administration of -NAME results in memory impairment for the inhibitory avoidance task. The effects of -NAME (100 mg/kg, ip) on retention were reversed in a dose-related manner by the centrally acting anticholinesterase physostigmine (35, 70, or 150 μg/kg, sc) administered 30 min after the NOS inhibitor. Further, -NAME (100 mg/kg, ip)-induced memory impairment was completely antagonized by the centrally acting muscarinic cholinergic agonist oxotremorine (OTM; 25, 50, or 100 μg/kg, sc) when given 30 min after -NAME. The peripherally acting anticholinesterase neostigmine (150 μg/kg, sc) did not modify the memory-impairing effects of -NAME. These findings suggest that the memory impairment following post-training administration of a NOS inhibitor is mediated, at least in part, by a reduction of the activity of central muscarinic cholinergic mechanisms and are consistent with our previous view that nitric oxide may be involved in post-training neural processes underlying the storage of newly acquired information.     

Effects of Posttraining Administration of Glucose on Retention of a Habituation Response in Mice: Participation of a Central Cholinergic Mechanism

Male Swiss mice were allowed to explore a novel environment, provided by an open-field activity chamber, for 10 min. The procedure was repeated twice with a 24-h interval. The difference in the exploratory activity between the first (training) and the second (testing) exposures to the chamber was taken as an index of retention of this habituation task. Posttraining intraperitoneal administration of glucose (10–300 mg/kg) enhanced retention in a dose-related manner, although only the dose of 30 mg/kg of glucose produced significant effects. Thus, the dose–response curve adopted an inverted U-shaped form. Glucose (30 mg/kg) given to untrained mice did not modify their exploratory performance when recorded 24 h later. The effects of glucose on retention were time-dependent, suggesting an action on memory storage. The memory-improving actions of glucose were prevented by the simultaneous administration of both the central acting muscarinic cholinergic antagonist atropine (0.5 mg/kg) and by the central acting nicotinic cholinergic antagonist mecamylamine (5 mg/kg). In contrast, neither methylatropine (0.5 mg/kg), a peripherally acting muscarinic receptor blocker, nor hexamethonium (5 mg/kg), a peripherally acting nicotinic receptor blocker, prevented the effects of glucose on retention. Low subeffective doses of glucose (10 mg/kg) and the central anticholinesterase physostigmine (35 μg/kg), but not neostigmine (35 μg/kg), given together, act synergistically and facilitated retention. We suggest that glucose modulates memory storage of one form of learning elicited by stimuli repeatedly presented without reinforcement, probably through an enhancement of brain acetylcholine synthesis and/or its release.     

死亡凸显对自我姓名注意瞬脱对抗效应的影响

已有研究表明死亡凸显会抑制自我面孔和自我参照记忆加工的自我优势,可是死亡凸显对自我姓名的影响尚不明确,本研究采用事件相关电位技术,探索死亡凸显对自我姓名注意瞬脱对抗效应及其大脑神经活动的影响。58名被试在经历不同的启动任务后,完成自我姓名、朋友姓名和名人姓名的注意瞬脱任务。行为结果发现自我姓名识别正确率显著高于朋友姓名和名人姓名,表现出稳定的自我姓名加工的注意瞬脱对抗效应;电生理数据发现死亡启动后自我姓名诱发的P300波幅显著低于消极启动组和中性启动组,而朋友姓名和名人姓名并不受启动的影响。本研究结果与以往研究结果共同表明死亡想法凸显会使个体将抑制自我加工（自我姓名、自我面孔和自我参照记忆）作为应对远端死亡焦虑的一种手段。     

Aptitude Tests: Can We Predict Their Future?

Garcia, J. The Logic and Limits of Mental Aptitude Testing. American Psychologist, 1981, 36, 1172–1180. Hargadon, F. Tests and College Admissions. American Psychologist, 1981, 36, 1112–1119.     

A faith for all seasons

A FAITH FOR ALL SEASONS:ISLAM AND WESTERN MODERNITY. By Shabbir Akhtar. London: Bellew Publishing, 1990. 251pp. Hb. £25.00. ISBN 0–947792–41–4.