Perirhinal cortex muscarinic receptor blockade impairs taste recognition memory formation

The relevance of perirhinal cortical cholinergic and glutamatergic neurotransmission for taste recognition memory and learned taste aversion was assessed by microinfusions of muscarinic (scopolamine), NMDA (AP-5), and AMPA (NBQX) receptor antagonists. Infusions of scopolamine, but not AP5 or NBQX, prevented the consolidation of taste recognition memory using attenuation of neophobia as an index. In addition, learned taste aversion in both short- and long-term memory tests was exclusively impaired by scopolamine. These data provide neurochemical support for the theory that cholinergic activity of the perirhinal cortex participates in the formation of the taste memory trace and that it is independent of the NMDA and AMPA receptor activity. These results support the idea that cholinergic neurotransmission in the perirhinal cortex is also essential for acquisition and consolidation of taste recognition memory.     

Protein synthesis underlies post-retrieval memory consolidation to a restricted degree only when updated information is obtained

Consolidation theory proposes that through the synthesis of new proteins recently acquired memories are strengthened over time into a stable long-term memory trace. However, evidence has accumulated suggesting that retrieved memory is susceptible to disruption, seeming to consolidate again (reconsolidate) to be retained in long-term storage. Here we show that intracortical blockade of protein synthesis in the gustatory cortex after retrieval of taste-recognition memory disrupts previously consolidated memory to a restricted degree only if the experience is updated. Our results suggest that retrieved memory can be modified as part of a mechanism for incorporating updated information into previously consolidated memory.     

The Refined Extension Principle for Semantics of Dynamic Logic Programming

Over recent years, various semantics have been proposed for dealing with updates in the setting of logic programs. The availability of different semantics naturally raises the question of which are most adequate to model updates. A systematic approach to face this question is to identify general principles against which such semantics could be evaluated. In this paper we motivate and introduce a new such principle the refined extension principle. Such principle is complied with by the stable model semantics for (single) logic programs. It turns out that none of the existing semantics for logic program updates, even though generalisations of the stable model semantics, comply with this principle. For this reason, we define a refinement of the dynamic stable model semantics for Dynamic Logic Programs that complies with the principle.     

The relationship between the need for closure and support for military action against Iraq: moderating effects of national attachment

A variety of studies suggest that a high need for closure--that is, a desire for knowledge that is clear, stable, and unambiguous as opposed to confusing or uncertain--may be associated with greater hostility toward relevant outgroups. Using international attitudes as the context, the authors examine the hypothesis that the relationship between the need for closure and support for military action against Iraq may be moderated by identification with the national ingroup. Specifically, it is expected that this relationship will be moderated by nationalism (i.e., an aggressive form of identification based on a desire for national dominance) but not patriotism (i.e., a more neutral love of one's country). The data provided a clear pattern of support for this hypothesis and additional analyses indicated that a high need for closure reduced variability about the use of force among the highly nationalistic but not the highly patriotic.     

Role of cholinergic system on the construction of memories: taste memory encoding

There is a large body of evidence suggesting that cholinergic activity is involved in memory processes. It seems that cholinergic activity is essential to learn several tasks and recent works suggest that acetylcholine plays an important role during the early stages of memory formation. In this review, we will discuss the results related to taste memory formation, focusing particularly on the conditioned taste aversion paradigm. We will first give evidence that nucleus basalis magnocellularis is involved in taste memory formation, due to its cholinergic projections. We then show that the cholinergic activity of the insular (gustatory) cortex is related to the taste novelty, and that the cholinergic signals initiated by novelty are crucial for taste memory formation. Then we present recent data indicating that cortical activation of muscarinic receptors is necessary for taste trace encoding, and also for its consolidation under certain circumstances. Finally, interactions between the cholinergic and other neuromodulatory systems inducing intracellular mechanisms related to plastic changes will be proposed as important processes underlying gustatory memory trace storage.     

Effects of early exposure to ventral gland odor on physical and behavioral development and adult social behavior in Mongolian gerbils.

Comparisons were made between male and female gerbils reared by ventral gland-excised and intact patents. Repeated measurements before and after puberty failed to reveal an effect of gland odor exposure on body weight, ventral gland size, open-field defecation, and time of vaginal opening. Exposed animals were more attracted than nonexposed animals to a strange male's gland odor during preference tests involving "marked" and "unmarked" paper strips. Opposite-sex pairs of exposed animals engaged in more social behavior than did nonexposed pairs, but there was no difference in fighting frequency or, during extended cohabiitation, in fecundity. While early exposure to gland odor apparently does not affect physical maturation, it may enhance later responsiveness to stimuli (gland odors) that are useful in locating conspecifics and that facilitate social interactions between previously unacquainted gerbils.     

Visual acuity improvement following fading and feedback training—III. Effects on acuity for stimuli in the natural environment

The effectiveness of Fading and Feedback training for improving visual performance of myopic volunteers was evaluated using a randomized control design. Forty-eight myopic volunteers were randomly assigned to one of four treatments: Fading and Feedback Training, Fading and Feedback Training plus Incentives, No Training, or No Training plus Incentives. Subjects were pre- and post-tested on three measures of visual function: Performance—subjects played a video “pong” game for a brief period of time; Facial Expression Identification—subjects were asked to identify four different facial expressions; and Visual Search—subjects were asked to locate four household items placed on tables in a room. Subjects in the training condition significantly improved in their ability to recognize facial expressions and identify household objects. This occurred with or without incentives for training subjects. However, for both the facial expression and visual search tasks, incentives alone resulted in improved visual acuity in the absence of training. These data are discussed in terms of generalizability of Fading and Feedback training to stimuli in the natural environment.     

What Can We Know of Computational Information? Measuring,Quantity, and Quality at Work in Programmable Artifacts

This paper explores the problem of knowledge in computational informational organisms, i.e. organisms that include a computing machinery at the artifact side. Although information can be understood in many ways, from the second half of the past century information is getting more and more digitised, von Neumann machines becoming dominant. Computational information is a challenge for the act of measuring, as neither purely quantitative nor totally qualitative approaches satisfy the need to explain the interplay among the agents producing and managing computational information. In this paper, Floridi’s method of levels of abstraction is applied to the analysis of computational information, with a chief interest in the concepts of information measure, quantification and quality.     

Dignity and Animals. Does it Make Sense to Apply the Concept of Dignity to all Sentient Beings?

Although the idea of dignity has always been applied to human beings and although its role is far from being uncontroversial, some recent works in animal ethics have tried to apply the idea of dignity to animals. The aim of this paper is to discuss critically whether these attempts are convincing and sensible. In order to assess these proposals, I put forward two formal conditions that any conception of dignity must meet (non-redundancy and normative determinacy) and outline three main approaches which might justify the application of dignity to animals: the species-based approach, moral individualism and the relational approach. Discussing in particular works by Martha Nussbaum and Michael Meyer I argue that no approach can convincingly justify the extension of dignity to animals because all fail to meet the formal conditions and do not provide an appropriate basis for animal dignity. I conclude by arguing that the recognition of the moral importance of animals and their defense should appeal to other normative concepts which are more appropriate than dignity.