Blockade of NR2B-Containing NMDA Receptors Prevents BDNF Enhancement of Glutamatergic Transmission in Hippocampal Neurons

Application of brain-derived neurotrophic factor (BDNF) to hippocampal neurons has profound effects on glutamatergic synaptic transmission. Both pre- and postsynaptic actions have been identified that depend on the age and type of preparation. To understand the nature of this diversity, we have begun to examine the mechanisms of BDNF action in cultured dissociated embryonic hippocampal neurons. Whole-cell patch-clamp recording during iontophoretic application of glutamate revealed that BDNF doubled the amplitude of induced inward current. Coexposure to BDNF and the NMDA receptor antagonist AP-5 markedly reduced, but did not entirely prevent, the increase in current. Coexposure to BDNF and ifenprodil, an NR2B subunit antagonist, reproduced the response observed with AP-5, suggesting BDNF primarily enhanced activity of NR2B-containing NMDA receptors with a lesser effect on non-NMDA receptors. Protein kinase involvement was confirmed with the broad spectrum inhibitor staurosporine, which prevented the response to BDNF. PKCI19-31 and H-89, selective antagonists of PKC and PKA, had no effect on the response to BDNF, whereas autocamtide-2-related inhibitory peptide, an antagonist of CaM kinase II, reduced response magnitude by 60%. These results demonstrate the predominant role of a specific NMDA receptor subtype in BDNF modulation of hippocampal synaptic transmission.     

Conversational remembering: Story recall with a peer versus for an experimenter

This research investigated the role social context plays in determining the content and organization of remembered information. As a manipulation of social context, subjects talked about a short story either with another subject (dyads) or for an experimenter (experimenter-tested). In addition, the instructions were manipulated: Subjects were asked about their memory of the story or their personal reactions to it. Regardless of instructions, the dyad subjects spoke more about their evaluations of the story, included more comments linking the story to a larger knowledge frame (metacomments), and more often used remembered details to support their positions. In contrast, the experimenter-tested subjects more often included story details and interpretations in narrative accounts of the story. The dyad subjects included in their recalls information that is part of story memory but seldom evidenced by single subjects remembering for an experiment. Thus conversational remembering often relies on a nonnarrative retrieval strategy. Regardless of social context, personal reaction instructions led to more meta-comments and evaluations, and less narrative than memory instructions. The organization and content of non-narrative conversational remembering may be explained by the dual demands of conforming to conversational rules and of establishing social bonds through self-revealing comments.     

Comparison of social time-out and activity time-out procedures in suppressing ethanol self-administration in alcoholics

The experiments compared the potencies of three different contingent time-out procedures for suppressing drinking in alcoholics, and also compared two different experimental methodologies for conducting such studies. In a residential research ward setting fourteen volunteer chronic alcoholics were given daily access to 17 alcoholic drinks provided that a minimum of 40 min elapsed between receiving successive drinks. Each drink contained 1 oz 95-proof ethanol in orange juice. During the baseline condition subjects were free to drink with no behavioral restrictions. However during the time-out conditions, specific behavioral restrictions were imposed on the subjects for the 40-min period following receipt of each drink. The results showed that Social time-out suppressed drinking to 71 per cent of baseline conditions, while Activity time-out and the combined Social and Activity time-out suppressed intake to 36 and 24 per cent, respectively. The study also demonstrated that similar experimental results were obtained when subjects were continuously exposed to the experimental conditions for a number of consecutive days. or intermittently exposed to different conditions in a mixed order over successive days.     

Imagery skill and preference in bilinguals

A number of studies have reported differences in the performance of bilinguals and monolinguals in verbal tasks. It has been suggested that one source of this difference is a greater tendency among bilinguals to use non-verbal ways of representing events, because of the potential for confusions between their two verbal codes. In the present study, bilingual and monolingual college students were compared on three dimensions of self-reported aspects of imagery—control, vividness and preference—as well as on a performance measure of spatial manipulation skill. When these tasks were preceded by a nominally verbal activity (prose comprehension), there were no group differences on the self-report or objective imagery measures. In contrast, when they were preceded by an imagery rating task, some evidence of a compensatory reliance on spatial codes among bilinguals was obtained. Implications of these task induction effects on both subjective and performance measures of a skill were discussed.     

Termination of psychoanalysis and September 11

In the United States, the last illusion of safety from problems in distant parts of the world was shattered on September 11, 2001. Psychoanalysts are in a unique position to both experience and examine how such a man-made social disaster becomes internalized and affects one's psychic reality by studying the effects of that day on patients already engaged in a psychoanalytic process. The author hypothesizes that in one such case, that of Mr. N, the termination phase was significantly affected. Furthermore, Mr. N's reaction to reading the analyst's clinical write-up further influenced the termination phase.     

The comparative effectiveness of distributed and colocated team after-action reviews

Despite their frequent use in the military and private sectors, the comparative effectiveness of colocated and distributed after-action reviews (AARs) is relatively unknown. Consequently, this study examined the comparative effectiveness of colocated and distributed AARs across taskwork and teamwork outcomes. Data were obtained from 492 participants randomly assigned to 123 four-person teams who participated in one of six AAR conditions. The results indicated that teams in the AAR conditions had significantly higher performance and team efficacy scores than the teams in the non-AAR conditions. In summary, the findings highlight that regardless of the training environment or type of AAR, the AAR remains an effective method at increasing performance and other outcomes. Therefore, the use of distributed AARs does not engender the posited process losses that were hypothesized.     

Going Gaga: Investigating,Creating, and Manipulating the Song Stuck in My Head

Summary: Having a song stuck in your head is a commonly experienced intrusive thought. We explored the intrusive song phenomenon through a survey, an experimental diary study, and three laboratory experiments. Contrary to the belief that only obnoxious songs get stuck, we found that songs people know and like frequently became intrusive. We also found that intrusive songs followed environmental cues. In addition, if a song continued to play in someone's head immediately after listening to it, the song was likely to return as an intrusive song within the next 24 hours. Similar to mind wandering, the return of intrusive songs depended on cognitive resources: people reported that intrusive songs returned during low cognitive load activities, and we found that overloading the cognitive systems with challenging activities increased intrusive song frequency. Throughout our studies, we easily created and manipulated intrusive song experiences. Songs provide a valuable method to investigate intrusive thoughts. Copyright © 2012 John Wiley & Sons, Ltd.