Kinetics of photoinduced changes in Ag nanoparticles deposited on an indium tin oxide surface

An enhancement of the UV-visible optical absorption spectra of Ag nanoparticles (NPs) deposited on indium tin oxide (ITO) surfaces of different resistance by a seed-mediated growth technique is presented. A bicolour coherent beam, obtained from a pulsed Nd:YAG laser providing a 1060-nm fundamental wavelength and a double-frequency one at 530?nm, was used. A significant change in the optical density is observed for Ag NPs on low-resistance ITO surfaces (≈4?Ω/square), while almost nothing occurs with high-resistance (≈50?Ω/square surfaces). The spectral position of the maximal absorption at 440?nm is almost preserved in both cases. This result is explained in terms of a local photoinduced static field and surface-plasmon polaritons interacting with photoexcited phonons. A grating effect, arising from the coherent bicolour light forming a superstructure as for quantum crystals, could be another contribution.     

Nucleation of recrystallization in fine-grained materials: an extension of the Bailey–Hirsch criterion

Abstract

A new criterion for nucleation in the case of dynamic recrystallization is proposed in order to include the contribution of the grain boundary energy stored in the microstructure in the energy balance. Due to the nucleation events, the total surface area of pre-existing grain boundaries decreases, leading to a nucleus size smaller than expected by conventional nucleation criteria. The new model provides a better prediction of the nucleus size during recrystallization of pure copper compared with the conventional nucleation criterion.     

Word length effects are not due to proactive interference

In immediate serial recall short words are better recalled than long words. The word length effect has become pivotal in the development of short-term memory models. The current research tests one explanation of the word length effect; that it is related to proactive interference (PI). We report two experiments in which the relationship is directly tested. In the first experiment we show that word length effects can be observed over the first few trials in an experiment and that the effect shows itself primarily in the number of omissions made. In the second experiment we simultaneously test for PI and word length effects. Strong word length effects were present but there was little evidence for PI influencing either overall levels of recall or the word length effect. In short, no empirical support was found for PI as an explanation of the word length effect.     

Episodic and semantic remote autobiographical memory in ageing

Many laboratory studies have demonstrated an age effect on episodic memory which is in contrast with the preservation of semantic memory. The aim of this study was the assessment of age effects on autobiographical memory according to the length of the retention interval, taking into account the episodic and semantic components. A total of 52 subjects, aged between 40 and 79, were divided into four age groups. They were tested with a sophisticated autobiographical questionnaire consisting of two tasks, one involving the recall of semantic information and another the recall of episodic events. Results revealed that episodic recall deteriorated more with age and retention interval than semantic recall. These data, gathered using an ecological test, confirm age differences demonstrated by laboratory tests on the episodic-semantic distinction. Furthermore, the profile of results obtained for the recall of specific detailed events, and analysed according to age of encoding, confirms the distribution of episodic memories across the lifespan, as modelled by Rubin, Wetzler, and Nebes (1986) with the cue-word technique.     

Power of the Circumplex: Incremental validity of intersection traits in predicting counterproductive work behaviors

This study examines the role of the circumplex model of personality in predicting counterproductive work behaviors (CWBs). Drawing on the fidelity‐bandwidth principle, we investigate the hypotheses that each of the three sets of circumplex traits representing the intersections of conscientiousness–agreeableness, conscientiousness–emotional stability, and agreeableness–emotional stability will account for significant incremental variance over five‐factor model (FFM) traits in predicting CWBs. Results indicated the circumplex traits contribute incremental variance over the FFM traits, are relatively more important than the FFM traits, and account for 1.5–2.0 times more variance in the total R² associated with CWBs. Collectively, these findings show that circumplex traits capture unique information not explained by FFM traits, and this information leads to a better understanding of the dispositional nature of CWBs.     

Count out your intrusions: Effects of verbal encoding on intrusive memories

Peri-traumatic information processing is thought to affect the development of intrusive trauma memories. This study aimed to replicate and improve the study by Holmes, Brewin, and Hennessy (2004, Exp. 3) on the role of peri-traumatic verbal processing in analogue traumatic intrusion development. Participants viewed an aversive film under one of three conditions: counting backwards in 3s (“verbal interference”), verbalising emotions and thoughts (“verbal enhancement”), or without an extra task. A dual-process account of PTSD would predict that verbal interference would increase intrusion frequency compared to no task, whereas verbal enhancement would lead to a decrease. In contrast, mainstream memory theory predicts a decrease in intrusion frequency from any concurrent task that diverts attention away from the trauma film. The main finding was that the verbal interference task led to a decrease in intrusive memories of the film compared to the other two conditions. This finding does not support a dual-process account of PTSD, but is in line with general theories of memory and attention.     

Laboratory vs. naturalistic prospective memory task predictions: young adults are overconfident outside of the laboratory

ABSTRACT

This study investigated whether individuals can predict their future prospective memory (PM) performance in a lab-based task and in a naturalistic task. Metacognitive awareness was assessed by asking participants to give judgments-of-learning (JOLs) on an item-level for the prospective (that something has to be done) and retrospective (what to do) PM component. In addition, to explore whether giving predictions influences PM performance, we compared a control group (without predictions) to a prediction group. Results revealed that giving predictions did not change PM performance. Moreover, participants were underconfident in their PM performance in the lab-based task, while they were overconfident in the naturalistic task. In addition, item-level JOLs indicated that they were inaccurate in predicting what items they will recall or not, but only for the prospective component of the PM task. As for the retrospective component, they were equally accurate in both task settings. This study suggests a dissociation of metacognitive awareness for PM according to both task setting and processing component.     

Memories defining the self in Alzheimer’s disease

ABSTRACT

There is a debate over the extent to which personal identity or the self is preserved in patients with Alzheimer’s disease (AD). Autobiographical memory deficits at early stages of AD could contribute to altering patients’ self. However, the nature of the relationship between autobiographical memory deficits and the self in AD has not been much investigated experimentally. In the present study, we aimed to investigate the integrative meaning of self-defining memories (SDMs) in early stages of AD and to analyse its relationship with the self-concept. The results showed that, when compared to the control group, AD patients less frequently extracted meaning from their SDMs and the meaning was less frequently tied to the self. Patients exhibited some altered aspects of the self-concept (i.e., complexity and strength), though some other components still persisted (i.e., valence and certainty). Correlation analyses showed that the impaired integrative meaning in the AD group was correlated with some changes in self-concept. We suggest that integrative meaning may act as a bridge between autobiographical memories and the self-concept, with reduced integration abilities appearing as a potential mechanism for the deterioration of the self-concept in AD.     

A systematic analysis of distressing near-death experience accounts

ABSTRACT

Near-death experiences (NDEs) are usually associated with positive affect, however, a small proportion are considered distressing. We aimed to look into the proportion of distressing NDEs in a sample of NDE narratives, categorise distressing narratives according to Greyson and Bush’s classification (inverse, void or hellish), and compare distressing and “classical” NDEs. Participants wrote down their experience, completed the Memory Characteristics Questionnaire (assessing the phenomenology of memories) and the Greyson scale (characterising content of NDEs). The proportion of suicidal attempts, content and intensity of distressing and classical NDEs were compared using frequentist and Bayesian statistics. Distressing NDEs represent 14% of our sample (n?=?123). We identified 8 inverse, 8 hellish and 1 void accounts. The proportion of suicide survivors is higher in distressing NDEs as compared to classical ones. Finally, memories of distressing NDEs appear as phenomenologically detailed as classical ones. Distressing NDEs deserve careful consideration to ensure their integration into experiencers’ identity.     

Age-related differences in episodic feeling-of-knowing arise from differences in memory performance

Previous studies about the effects of ageing on the episodic feeling-of-knowing (FOK) accuracy and its underlying processes have yielded conflicting results. Recent work suggests that using alternative measures to gamma correlations might allow more accurate and informative interpretations of metamemory performance in ageing. We therefore investigated this issue with a large sample of 59 young and 61 older participants using alternative signal-detection theory (SDT) measures. These measures (receiver operating characteristic curves and Brier score) are recommended in the literature and able to reveal the characteristic profile of impairment in ageing. Our results suggest that the FOK accuracy deficit observed in the literature arises from differences in memory performance. This observation provides a convenient explanation to the previous discrepancies and furthermore supports the interest of the use of SDT-derived measures in the frame of metamemory.