The revelation effect for autobiographical memory: A mixture-model analysis

Participants provided information about their childhood by rating their confidence about whether they had experienced various events (e.g., “broke a window playing ball”). On some trials, participants unscrambled a key word from the event phrase (e.g., wdinwo—window) or an unrelated word (e.g., gnutge—nugget) before seeing the event and giving their confidence ratings. The act of unscrambling led participants to increase their confidence that the event occurred in their childhood, but only when the confidence rating immediately followed the act of unscrambling. This increase in confidence mirrors the “revelation effect” observed in word recognition experiments. In the present article, we analyzed our data using a new signal detection mixture distribution model that does not require the researcher to know the veracity of memory judgments a priori. Our analysis reveals that unscrambling a key word or an unrelated word affects response bias and discriminability in autobiographical memory tests in ways that are very similar to those that have been previously found for word recognition tasks.     

Emotion Regulation and the Anxiety Disorders: An Integrative Review

The construct of emotion regulation has been increasingly investigated in the last decade, and this work has important implications for advancing anxiety disorder theory. This paper reviews research demonstrating that: 1) emotion (i.e., fear and anxiety) and emotion regulation are distinct, non-redundant, constructs that can be differentiated at the conceptual, behavioral, and neural levels of analysis; 2) emotion regulation can augment or diminish fear, depending on the emotion regulation strategy employed; and 3) measures of emotion regulation explain incremental variance in anxiety disorder symptoms above and beyond the variance explained by measures of emotional reactivity. The authors propose a model by which emotion regulation may function in the etiology of anxiety disorders. The paper concludes with suggestions for future research.     

AMPA/kainate, NMDA, and dopamine D1 receptor function in the nucleus accumbens core: a context-limited role in the encoding and consolidation of instrumental memory

Neural integration of glutamate- and dopamine-coded signals within the nucleus accumbens (NAc) is a fundamental process governing cellular plasticity underlying reward-related learning. Intra-NAc core blockade of NMDA or D1 receptors in rats impairs instrumental learning (lever-pressing for sugar pellets), but it is not known during which phase of learning (acquisition or consolidation) these receptors are recruited, nor is it known what role AMPA/kainate receptors have in these processes. Here we show that pre-trial intra-NAc core administration of the NMDA, AMPA/KA, and D1 receptor antagonists AP-5 (1 microg/0.5 microL), LY293558 (0.01 or 0.1 microg/0.5 microL), and SCH23390 (1 microg/0.5 microL), respectively, impaired acquisition of a lever-pressing response, whereas post-trial administration left memory consolidation unaffected. An analysis of the microstructure of behavior while rats were under the influence of these drugs revealed that glutamatergic and dopaminergic signals contribute differentially to critical aspects of the initial, randomly emitted behaviors that enable reinforcement learning. Thus, glutamate and dopamine receptors are activated in a time-limited fashion-only being required while the animals are actively engaged in the learning context.     

A refined model of sleep and the time course of memory formation

Research in the neurosciences continues to provide evidence that sleep plays a role in the processes of learning and memory. There is less of a consensus, however, regarding the precise stages of memory development during which sleep is considered a requirement, simply favorable, or not important. This article begins with an overview of recent studies regarding sleep and learning, predominantly in the procedural memory domain, and is measured against our current understanding of the mechanisms that govern memory formation. Based on these considerations, I offer a new neurocognitive framework of procedural learning, consisting first of acquisition, followed by two specific stages of consolidation, one involving a process of stabilization, the other involving enhancement, whereby delayed learning occurs. Psychophysiological evidence indicates that initial acquisition does not rely fundamentally on sleep. This also appears to be true for the stabilization phase of consolidation, with durable representations, resistant to interference, clearly developing in a successful manner during time awake (or just time, per se). In contrast, the consolidation stage, resulting in additional/enhanced learning in the absence of further rehearsal, does appear to rely on the process of sleep, with evidence for specific sleep-stage dependencies across the procedural domain. Evaluations at a molecular, cellular, and systems level currently offer several sleep specific candidates that could play a role in sleep-dependent learning. These include the upregulation of select plasticity-associated genes, increased protein synthesis, changes in neurotransmitter concentration, and specific electrical events in neuronal networks that modulate synaptic potentiation.     

The effects of morphine on the production and discrimination of interresponse times

Recent experiments suggest that the effects of drugs of abuse on the discrimination of the passage of time may differ for experimenter-imposed and subject-produced events. The current experiment examined this suggestion by determining the effects of morphine on the discrimination of interresponse times (IRTs). Pigeons pecked a center key on a random-interval 20-s schedule of matching-to-sample trials. Once the interval had timed out, a choice trial randomly followed either a short (2- to 3-s) or long (6- to 9-s) IRT on the center key. Pecking the side key lit one color produced food after a short IRT, and pecking the side key lit the other color produced food after a long IRT. Two experimental phases differed in the functional role of the different key colors. Under control conditions, the IRT distributions had two modes, one at the lower bound of the short category and a smaller one at the lower bound of the long category. Pigeons accurately categorized the duration of the IRTs: One key color was pecked following short IRTs and the other key color was pecked following long IRTs. Morphine flattened the IRT distribution and reduced the accuracy of categorizing IRTs. Categorization of long IRTs was particularly disrupted. Morphine did not produce overestimation of time as assessed by the production or categorization of IRTs. These results are similar to those obtained previously for the effects of morphine on the discrimination of the duration of experimenter-imposed events.     

Responsibility and evil imagination

In this Niebuhrian perspective on hostile and violent discourse the author utilizes H. R. Niebuhr's fourfold notion of responsibility and his concept of evil imagination to examine relations marred by protracted hostility toward hated other or others. The author argues that violent and hostile discourse manifests a particular form of responsibility whereby persons expressing hostility toward hated others construct, by way of negative representations, maligned histories and identities for the other and at the same time construct an idealized or glorified history and identity for themselves. These positive and negative representations and histories, then, are utilized to answer questions regarding interpretation, accountability, and solidarity. Niebuhr's concept of evil imagination is employed to hypothesize about the intransigence of this form of responsibility and to suggest reasons why elevated and maligned representations, identities, and histories are, more often than not, inextricably and tragically linked.