Modeling recall memory for emotional objects in Alzheimer's disease

ABSTRACT

Objective: To examine whether emotional memory (EM) of objects with self-reference in Alzheimer's disease (AD) can be modeled with binomial logistic regression in a free recall and an object recognition test to predict EM enhancement.?Method: Twenty patients with AD and twenty healthy controls were studied. Six objects (three presented as gifts) were shown to each participant. Ten minutes later, a free recall and a recognition test were applied. The recognition test had target–objects mixed with six similar distracter objects. Participants were asked to name any object in the recall test and identify each object in the recognition test as known or unknown.?Results: The total of gift objects recalled in AD patients (41.6%) was larger than neutral objects (13.3%) and a significant EM recall effect for gifts was found (Wilcoxon: p < .003). EM was not found for recognition in AD patients due to a ceiling effect. Healthy older adults scored overall higher in recall and recognition but showed no EM enhancement due to a ceiling effect. A logistic regression showed that likelihood of emotional recall memory can be modeled as a function of MMSE score (p < .014) and object status (p < .0001) as gift or non-gift.?Conclusion: Recall memory was enhanced in AD patients for emotional objects indicating that EM in mild to moderate AD although impaired can be provoked with strong emotional load. The logistic regression model suggests that EM declines with the progression of AD rather than disrupts and may be a useful tool for evaluating magnitude of emotional load.     

Connecting Experience and Economy—Aspects of Disguised Positioning

The focus of this article is the use of experience made within the literature of the “new” economical discipline of experience economy. By combining a methodological individualism with a causal and dehumanising picture of the process of experience, this discipline conceives economic interactions as acts of autonomy. These acts, it is claimed, are part of economical instrumental reason restructuring itself by using experiences as tools in convincing consumers that they are free to pursue their respective paths of lives. Described through the use of positioning theory, however, this turns out to be a result of an effort of equipping consumers with a new economic norm of forced positioning disguised as deliberate self-positioning.     

Quine's Nihilism

Quine is an important philosopher. The point of departure of his philosophical enterprise is sound: his down to earth naturalism, his scientism and behaviourism. However, he tends to get carried away by it, when he goes to extremes – and ends up in nihilism. It is certainly true that we can never quite rule out the possibility that we have misunderstood another person. And what he or she means is a consequence mainly of two things. It is a consequence of his actual intention with the utterance and also, to some extent, of the way the world actually is. This is not to say, however, that there is no fact of the matter. While there is underdetermination by actual evidence of interpretation there is no such thing as indeterminacy of translation (or interpretation). While there may well exist conflicting empirically adequate theories, there is no room for ontological relativity. Some of these theories may be the right one and the others wrong, even if this is something we cannot even in principle decide on empirical grounds.     

Agonistic behavior and growth in newly emerged brown trout (Salmo trutta L) of sea‐ranched and wild origin

Selection experiments and game theory models have revealed that the changes in agonistic behavior following selection for rapid growth rate of fish depend on the access of food. If food is spatially restricted and in excess of demand, the intensity of agonistic behaviors will decrease. This prediction was tested in an experiment on wild and sea‐ranched brown trout (Salmo trutta L.) fry originating from a common stock. Agonistic behavior, activity, and specific growth rate were studied in tanks (56 × 56 cm) at high (159.4 fry/m²) and low (9.6 fry/m²) stocking densities given either a large or small food ration (3.0% and 1.5%, respectively, food per total body weight and day). Observations were done during 4 days in each trial. Generally, fry of sea‐ranched origin had a higher growth rate. No differences in activity were found. Intensity of agonistic behavior was higher among wild groups. There was a tendency for interaction between density and strain, e.g., wild fish were relatively more aggressive at higher densities. Food ration had no effect on level of agonistic behavior. These results indicate that the selection for rapid growth in hatcheries may indirectly select for reduced aggressiveness. Genetic integrity and diversity of wild populations may be threatened when interbreeding occurs between wild and hatchery fish. Aggr. Behav. 28:145–153, 2002. © 2002 Wiley‐Liss, Inc.     

Operant Reward Learning in Aplysia

Anticipating the future has a decided evolutionary advantage, and researchers have found many evolutionarily conserved mechanisms by which humans and animals learn to predict future events. Researchers often study such learned behavior using conditioning experiments. The marine snail Aplysia has been at the forefront of research into the cellular and molecular mechanisms of classical conditioning. Recently, Aplysia has also gained a reputation as a valuable model system for operant reward learning. Its feeding behavior can be operantly conditioned in the intact animal as well as in reduced preparations of the nervous system. The reward signal relies on dopamine transmission and acts in conjunction with activity in an identified neuron (B51) to bring about operant memory.