Roles for Drosophila mushroom body neurons in olfactory learning and memory

Olfactory learning assays in Drosophila have revealed that distinct brain structures known as mushroom bodies (MBs) are critical for the associative learning and memory of olfactory stimuli. However, the precise roles of the different neurons comprising the MBs are still under debate. The confusion surrounding the roles of the different neurons may be due, in part, to the use of different odors as conditioned stimuli in previous studies. We investigated the requirements for the different MB neurons, specifically the alpha/beta versus the gamma neurons, and whether olfactory learning is supported by different subsets of MB neurons irrespective of the odors used as conditioned stimuli. We expressed the rutabaga (rut)-encoded adenylyl cyclase in either the gamma or alpha/beta neurons and examined the effects on restoring olfactory associative learning and memory of rut mutant flies. We also expressed a temperature-sensitive shibire (shi) transgene in these neuron sets and examined the effects of disrupting synaptic vesicle recycling on Drosophila olfactory learning. Our results indicate that although we did not detect odor-pair-specific learning using GAL4 drivers that primarily express in gamma neurons, expression of the transgenes in a subset of alpha/beta neurons resulted in both odor-pair-specific rescue of the rut defect as well as odor-pair-specific disruption of learning using shi(ts1).     

Behavioral and neurophysiological correlates of episodic coding,proactive interference,and list length effects in a running span verbal working memory task

Updating refers to (1) discarding items from, (2) repositioning items in, and (3) adding items to a running working memory span. Our behavioral and fMRI experiments varied three factors: trial length, proactive interference (PI), and group integrity. Group integrity reflected whether the grouping of items at the encoding stage was violated at discarding. Behavioral results were consistent with the idea that updating processes have a relatively short refractory period and may not fatigue, and they revealed that episodic information about group context is encoded automatically in working memory stimulus representations. The fMRI results did not show evidence that updating requirements in a task recruit executive control processes other than those supporting performance on nonupdating trials. They did reveal an item-accumulation effect, in which signal increased monotonically with the number of items presented during the trial, despite the insensitivity of behavioral measures to this factor. Behavioral and fMRI correlates of PI extended previous results and rejected an alternative explanation of PI effects in working memory.     

Long-term Effects of Subliminal Priming on Academic Performance

This research examines the temporal range of subliminal priming effects on complex behavior. In Experiments 1 and 2, participants were subliminally primed with words either related or unrelated to intelligence before completing a practice exam, administered 1 to 4 days before an actual course midterm. Results revealed that the intelligence primes increased performance on the midterm compared to neutral primes. Experiment 1 demonstrated that being told that the priming task was designed to help exam performance moderated the effect of the intelligence primes. In Experiment 2, practice test performance mediated the effect of the primes on midterm performance. These experiments demonstrated that subliminal priming may have long-term effects on real-world behavior, and demonstrates one means by which long-term priming effects may occur.     

Anxiety and impression formation: Direct information rather than priming explains affect-congruity

Both affect-priming and affect-as-information theories predict that when people are anxious they will form affect-congruent impressions of others, but via different mechanisms. Affect-priming asserts that memory mediates the influence of anxiety on judgement, whereas affect-as-information asserts that people attribute anxiety to the target of judgement. As these theories predicted, anxious participants in Study 1 found an impression-formation target to be more threatening than did control participants. However, this effect was not mediated by memory, and was attenuated in Study 2 when anxious participants attributed their affect to a source other than the target. These findings suggest that anxious people form affect-congruent impressions of others because they attribute their anxiety to the impression-formation target rather than because anxiety primes affect-congruent memory.     

History of a Childhood Neurosis and Its Relation to the Adult Superego

The purpose of this paper is to find meaning for the “presence of conscience” observable in the psychoanalytic setting and corresponding evidence for the origins of such ways of thinking, feeling, and remembering. I apply this perspective to the case study of a man who presented as constricted, inhibited, anxious, and self-critical. He was outwardly successful but internally tormented with what can best be described as an obsessional neurosis. His initial symptomatic neurosis was supplanted by a transference neurosis reflecting a childhood obsessional neurosis. In my theory of mind during this analysis, I often saw the original ideas of Freud at work—unconscious sense of guilt, ego ideal, and conscience. The analysand represented over and over the dynamics of the Oedipus stage of development. I made additional observations about character formation and guilt. The analysand terminated his work with me symptom-free. From this case study, I learned that the presence of conscience (guilt and self-denigration), or of superego structure and function in classical terms, is best approached as to origin by following the development of self in reference to the other.     

Is academic buoyancy anything more than adaptive coping?

Abstract

Academic buoyancy refers to a positive, constructive, and adaptive response to the types of challenges and setbacks experienced in a typical and everyday academic setting. In this project we examined whether academic buoyancy explained any additional variance in test anxiety over and above that explained by coping. Two hundred and ninety-eight students in their final two years of compulsory schooling completed self-report measures of academic buoyancy, coping, and test anxiety. Results suggested that buoyancy was inversely related to test anxiety and unrelated to coping. With the exception of test-irrelevant thoughts, test anxiety was positively related to avoidance coping and social support. Test-irrelevant thoughts were inversely related to task focus, unrelated to social support, and positively related to avoidance. A hierarchical regression analysis showed that academic buoyancy explained a significant additional proportion of variance in test anxiety when the variance for coping had already been accounted for. These findings suggest that academic buoyancy can be considered as a distinct construct from that of adaptive coping.