Flashbulb memories of personal events of 9/11 and the day after for a sample of New York City residents

The present study assessed consistency of recollections of personal circumstances of the 9/11 World Trade Center attack and events of the day before (9/10), and the day after (9/12), in a sample of 100 New York City college students. The day before 9/11 represented an ordinary event. A questionnaire was administered twice, 1 wk. and 1 yr. after the 9/11 attack. Students were asked to describe their personal circumstances when hearing about the news of the World Trade Center attack and for the same time of day for 9/10 and 9/12. 18 students returned the follow-up questionnaire. Consistency of initial and follow-up responses for the central categories for both 9/11 and 9/12 of where, who, and activity was very high (9/11: "Where"--100%, "Who"--100%, "What"--94%; 9/12: "Where"--100%, "Who"--100%, "What"--80%). Recollections of 9/10 were significantly less consistent ("Where"--79%, "Who"--71%, "What"--71%). Analysis indicated that students formed vivid, consistent recollections during the events of both 9/11 and 9/12. It is likely that the events of 9/12 also became flashbulb memories, vivid recollections of traumatic events, because the emotional impact of the stressful events, i.e., police and military presence, disrupted schedules, relating to the 9/11 attack endured beyond the day of the attack.     

The relationship between dominance rank and spatial ability among male meadow voles (Microtus pennsylvanicus)

Males of many mammalian species exhibit contest competition and scramble competition for mates, but the relationship between these 2 forms of competition remains poorly understood. The authors measured dominance rank and spatial ability as traits likely to be selected by contest and scramble competition, respectively, among male meadow voles (Microtus pennsylvanicus). The spatial ability of males was assessed using water maze tests, and dominance rank was determined using paired trials in a neutral arena. Dominant males had better spatial-learning ability and tended to have quicker learning speed but did not have better spatial memory than less aggressive subordinates. Therefore, the authors found no evidence that contest and scramble competition have favored alternative reproductive phenotypes among male meadow voles.     

The Art of Buying: Coming to Terms with Money and Materialism

Money and possessions hold strong attractions, but being driven to acquire them in order to enhance one's social standing is associated with lowered well-being. Literatures on money and happiness, materialism, and cultural mediators are reviewed. Consumer well-being is associated with being neither very tight nor very loose with money, with having relatively low financial aspirations, and with being low in materialism. Price-related behaviors – whether to spend low, spend high, or attempt to maximize value – are ways of responding to economic outlay vis-à-vis material wants, and these "strategies" offer a window into broader consumer lifestyles: the Value Seeker type is tight with money and materialistic; the Big Spender is loose with money and materialistic; the Non-Spender is tight with money and not materialistic; and the Experiencer is loose with money and not materialistic. Each of these types is described in terms of the potentials for well-being as well as the risks. Intrinsic motivation emerges as a key to well-being. This revised version was published online in August 2006 with corrections to the Cover Date.     

Age-dependent glutamate induction of synaptic plasticity in cultured hippocampal neurons

A common denominator for the induction of morphological and functional plasticity in cultured hippocampal neurons involves the activation of excitatory synapses. We now demonstrate massive morphological plasticity in mature cultured hippocampal neurons caused by a brief exposure to glutamate. This plasticity involves a slow, 70%-80% increase in spine cross-section area associated with a significant reduction in the width of dendrites. These changes are age dependent and expressed only in cells >18 d in vitro (DIV). Activation of both NMDARs and AMPARs as well as a sustained rise of internal calcium levels are necessary for induction of this plasticity. On the other hand, blockade of network activity or mGluRs does not abolish the observed morphological plasticity. Electrophysiologically, a brief exposure to glutamate induces an increase in the magnitude of EPSCs evoked between pairs of neurons, as well as in mEPSC frequency and amplitude, in mature but not young cultures. These results demonstrate an age-dependent, rapid and robust morphological and functional change in cultured central neurons that may contribute to their ability to express long term synaptic plasticity.     

Developing Sustainability: A New Metaphor for Progress

In this paper, we propose a new model for development, one that transcends the North–South dichotomy and goes beyond a narrow conception of development as an economic process. This model requires a paradigm shift toward a new metaphor that develops sustainability, rather than sustains development. We conclude by defending a ‘report card on development’ as a means for evaluating how countries perform within this new paradigm.     

Time-dependent modulation of inhibitory avoidance memory by spermidine in rats

The polyamines, spermine, spermidine, and putrescine, are a group of aliphatic amines that may act as physiological modulators of N-methyl-D-aspartate (NMDA) receptors. Although the modulatory role of polyamines in NMDA receptor function has long been known, the effects of polyamines on learning and memory only recently began to be unraveled. In the present study, we investigated the effect of bilateral infusions of spermidine (0.02-2 nmol), a polyamine agonist, into the CA1 region of the rat dorsal hippocampus on inhibitory avoidance learning 30 min pre-training, immediately post-training, 6 h post-training, or 10 min pre-test. Bilateral microinjections of 0.2 nmol spermidine prolonged step-down latencies compared to the respective control group when administered 30 min pre-training or immediately post-training. These results provide evidence that the modulatory effects of spermidine on the acquisition and/or early consolidation of memory of inhibitory avoidance tasks in the hippocampus occur within a limited time window.     

Effects of semantic cues on mathematical modeling: Evidence from word-problem solving and equation construction tasks

Mathematical solutions to textbook word problems are correlated with semantic relations between the objects described in the problem texts. In particular, division problems usually involve functionally related objects (e.g., tulips-vases) and rarely involve categorically related objects (e.g., tulips-daisies). We examined whether middle school, high school, and college students use object relations when they solve division word problems (WP) or perform the less familiar task of representing verbal statements with algebraic equations (EQ). Both tasks involved multiplicative comparison statements with either categorically or functionally related objects (e.g., "four times as many cupcakes [commuters] as brownies [automobiles]"). Object relations affected the frequency of correct solutions in the WP task but not in the EQ task. In the latter task, object relations did affect the structure of nonalgebraic equation errors. We argue that students use object relations as "semantic cues" when they engage in the sense-making activity of mathematical modeling.