BACKGROUND Enhanced acquisition and delayed extinction of fear conditioning are viewed as major determinants of anxiety disorders, which are often characterized by a dysfunctional hypothalamic-pituitary-adrenal (HPA) axis. METHOD In this study we employed cued fear conditioning in two independent samples of healthy subjects (sample 1: n=60, sample 2: n=52). Two graphical shapes served as cond...

Social fears emerging in adolescence can have negative effects on emotional well-being. Yet the mechanisms by which these risks occur are unknown. One possibility is that associative learning results in fears to previously neutral social stimuli. Such conditioned responses may alter subsequent processing of social stimuli. We used a novel conditioning task to examine how associative processes i...

The role of sound in Drosophila melanogaster courtship, along with its perception via the antennae, is well established, as is the ability of this fly to learn in classical conditioning protocols. Here, we demonstrate that a neutral acoustic stimulus paired with a sucrose reward can be used to condition the proboscis-extension reflex, part of normal feeding behavior. This appetitive conditionin...

One-hundred and twenty-eight college students participated in an experiment designed to examine facilitatory and inhibitory effects of instructions on the GSR index of the orienting reflex. One aspect of the study examined effects of instructions on verbal differential semantic conditioning of the aSR and conventional differential semantic conditioning requiring discovery of the CS-US contingen...

Colours are quickly learnt by free-moving bees in operant conditioning settings. In the present study, we report a method using the classical conditioning of the proboscis extension response (PER) in restrained honeybees (Apis mellifera), which allows bees to learn colours after just a few training trials. We further analysed how visual learning and discrimination is influenced by the quality o...

The basal ganglia are a collection of subcortical nuclei thought to underlie a wide variety of vertebrate behavior. Although a great deal is known about the functional and physiological properties of the basal ganglia, relatively few models have been formally developed that have been tested against both behavioral and physiological data. Our previous work (Ashby & Crossley, 2011, J. of Cognitiv...

Although exogenous cannabinoid ligands such as delta9-tetrahydrocannabinol (THC) have been implicated in reward-related learning and aversion, the hedonic effects of the endogenous cannabinoid agonist anandamide (arachidonylethanolamide) have never been assessed. Thus, the effects of anandamide were tested in a place conditioning task. Male Wistar rats received THC (0.0-8.0 mg/kg) or anandamide...

PURPOSE/OBJECTIVES To provide clinical insights into dosing and administration of IV busulfan, a conditioning agent for hematopoietic stem cell transplantation (HSCT). DATA SOURCES Review of published literature related to busulfan pretransplant conditioning using MEDLINE. Meeting abstracts, investigational protocols, and pharmaceutical manufacturers' package inserts also were reviewed. DAT...

In this paper we propose a new approach to probabilistic inference on belief networks, global conditioning, which is a simple gener­ alization of Pearl's (1986b) method of loop­ cutset conditioning. We show that global conditioning, as well as loop--cutset condition­ ing, can be thought of as a special case of the method of Lauritzen and Spiegelhalter (1988) as refined by Jensen et al (1990a; 1...

The construction of a well-conditioned integral equation for iterative solution of scattering problems with a variable Leontovitch boundary condition is proposed. A suitable parametrix is obtained by using a new unknown and an approximation of the transparency condition. We prove the well-posedness of the equation for any wavenumber. Finally, some numerical comparisons with well-tried method pr...