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41.
Finding reemployment after job loss is a complex and difficult task that requires extensive motivation and self‐regulation. This study aimed to examine whether improving unemployed job seekers’ cognitive self‐regulation can increase reemployment probabilities. Based on the goal orientation literature, we developed a learning‐goal orientation (LGO) training, which focused on goal setting aimed at improving rather than demonstrating competences and creating a climate of development and improvement. We predicted that the LGO training would influence peoples’ goal orientation towards job seeking, which in turn would relate to learning from failure, strategy awareness, and self‐efficacy, leading to job‐search intentions, resulting in increased reemployment status. Using a 2‐group quasi‐experimental design with 223 unemployed job seekers, we found support for these predictions, except for self‐efficacy. The results suggest that an LGO training is a promising tool to improve self‐regulation in and effectiveness of job search.  相似文献   
42.
High-frequency oscillations, known as sharp-wave/ripple (SPW-R) complexes occurring in hippocampus during slow-wave sleep (SWS), have been proposed to promote synaptic plasticity necessary for memory consolidation. We recorded sleep for 3 h after rats were trained on an odor-reward association task. Learning resulted in an increased number SPW-Rs during the first hour of post-learning SWS. The magnitude of ripple events and their duration were also elevated for up to 2 h after the newly formed memory. Rats that did not learn the discrimination during the training session did not show any change in SPW-Rs. Successful retrieval from remote memory was likewise accompanied by an increase in SPW-R density and magnitude, relative to the previously recorded baseline, but the effects were much shorter lasting and did not include increases in ripple duration and amplitude. A short-lasting increase of ripple activity was also observed when rats were rewarded for performing a motor component of the task only. There were no increases in ripple activity after habituation to the experimental environment. These experiments show that the characteristics of hippocampal high-frequency oscillations during SWS are affected by prior behavioral experience. Associative learning induces robust and sustained (up to 2 h) changes in several SPW-R characteristics, while after retrieval from remote memory or performance of a well-trained procedural aspect of the task, only transient changes in ripple density were induced.  相似文献   
43.
Sleep has been shown to promote the generation of explicit knowledge as indicated by the gain of insight into previously unrecognized task regularities. Here, we explored whether this generation of explicit knowledge depends on pre-sleep implicit knowledge, and specified the differential roles of slow-wave sleep (SWS) vs. rapid eye movement (REM) sleep in this process. Implicit and explicit knowledge (insight) related to a hidden regularity were assessed in an associative motor-learning task (number reduction task, NRT), which was performed in two sessions (initial practice and retest) separated by 3 h of either early-night sleep, rich in SWS, or of late-night sleep, rich in REM sleep. About half of the participants developed signs of implicit rule knowledge (i.e., speeded reaction times for responses determined by the hidden regularity) at initial practice preceding early or late sleep. Of these, half developed explicit knowledge across early-night sleep, significantly more than across late-night sleep. In contrast, late-night subjects preferentially remained on the level of implicit rule knowledge after sleep. Participants who did not develop implicit knowledge before sleep had comparable rates of transition to implicit or explicit knowledge across early and late sleep. If subjects gained explicit knowledge across sleep, this was associated with lower amounts of REM sleep, specifically in the late-night group. SWS predominant during the early night may restructure implicit memory representations in a way that allows creating an explicit representation afterward, whereas REM sleep in the late night appears to stabilize them in their implicit form.  相似文献   
44.
While there is mounting evidence for the importance of sleep for declarative memory consolidation in adults, so far this issue has not been investigated in children despite considerable differences in sleep duration and sleep architecture between children and adults. Here, 27 children (aged between 9 and 12yr) were examined on two conditions: on the Sleep-Wake condition, subjects learned word pairs in the evening and delayed recall was tested first in the next morning after sleep and then again in the following evening after daytime wakefulness. On the Wake-Sleep condition, learning took place in the morning and delayed recall was tested in the evening of the same day and again in the next morning after sleep. In both conditions retention of declarative memory was significantly increased only after an interval of sleep that either followed immediately after learning (as in the Sleep-Wake condition) or that followed after daytime wakefulness (as in the Wake-Sleep condition), respectively. The results support the hypothesis that sleep plays an active role in declarative memory consolidation even if delayed and further show for the first time the importance of sleep for declarative memory consolidation during childhood.  相似文献   
45.
Saccadic reaction time (SRT) is more strongly slowed by target-similar than dissimilar distractors (similarity effect). The time course of this similarity effect was investigated by varying target contrast and analyzing SRT distributions. With foveal distractors, the similarity effect increased with increasing SRT, suggesting that top-down enhancement of target features increased over time. This allowed for successful saccades to the peripheral target, but also entailed larger distraction by target-similar stimuli. Similarity effects with peripheral distractors did not increase with SRT, which we attribute to location-based inhibition containing the growing enhancement of target features. Strong inhibition was likely with peripheral distractors because they always appeared at the same task-irrelevant location. Prior inhibition with foveal distractors was weaker because this would have partially released fixation and entailed anticipations.  相似文献   
46.
According to the active system consolidation theory, memory consolidation during sleep relies on the reactivation of newly encoded memory representations. This reactivation is orchestrated by the interplay of sleep slow oscillations, spindles, and theta, which are in turn modulated by certain neurotransmitters like GABA to enable long-lasting plastic changes in the memory store. Here we asked whether the GABAergic system and associated changes in sleep oscillations are functionally related to memory reactivation during sleep. We administered the GABAA agonist zolpidem (10 mg) in a double-blind placebo-controlled study. To specifically focus on the effects on memory reactivation during sleep, we experimentally induced such reactivations by targeted memory reactivation (TMR) with learning-associated reminder cues presented during post-learning slow-wave sleep (SWS). Zolpidem significantly enhanced memory performance with TMR during sleep compared with placebo. Zolpidem also increased the coupling of fast spindles and theta to slow oscillations, although overall the power of slow spindles and theta was reduced compared with placebo. In an uncorrected exploratory analysis, memory performance was associated with slow spindle responses to TMR in the zolpidem condition, whereas it was associated with fast spindle responses in placebo. These findings provide tentative first evidence that GABAergic activity may be functionally implicated in memory reactivation processes during sleep, possibly via its effects on slow oscillations, spindles and theta as well as their interplay.

Sleep supports the consolidation of newly acquired memories (Mednick et al. 2011; Klinzing et al. 2019). According to the active system consolidation theory, new memories and their associated neuronal activation patterns become spontaneously reactivated (replayed) following learning in the sleeping brain (Wilson and McNaughton 1994; Diekelmann and Born 2010). These reactivations allow for the redistribution and integration of the memory representations from hippocampal to neocortical sites for long-term storage (Rasch and Born 2007; Klinzing et al. 2019). Memory reactivation during sleep has been proposed to rely on the synchronized interplay of electrophysiological oscillations characteristic of non–rapid eye movement (NREM) sleep, mainly neocortical slow oscillations (SOs, <1 Hz), thalamocortical spindles (9–15 Hz), and hippocampal ripples (80–200 Hz) (Mölle et al. 2009; Staresina et al. 2015; Helfrich et al. 2018; Ngo et al. 2020). Particularly, sleep spindles and their intricate phase coupling to SO have been suggested to be mechanistically involved in memory consolidation processes during sleep (Ulrich 2016; Antony et al. 2019). It has been proposed that memories become reinstated by spindle events, specifically during the up-state of slow oscillations, allowing for the flow of information between different brain sites as well as the induction of lasting structural and functional plastic changes in the learning-associated neuronal networks (Rosanova and Ulrich 2005; Peyrache and Seibt 2020). In addition to sleep spindles, neocortical and hippocampal theta activity (4–8 Hz) is also phase-locked to SO during NREM sleep (Gonzalez et al. 2018; Cox et al. 2019; Krugliakova et al. 2020), and this coupling has been related to memory consolidation during sleep (Schreiner et al. 2018).A number of neuromodulators seem to be involved in the generation of sleep spindles, SO and associated memory processing, most notably GABA (γ-aminobutyric acid), which is the major inhibitory neurotransmitter (Lancel 1999; Ulrich et al. 2018). Sleep spindles and sleep-dependent memory processing can be boosted by targeting the GABAergic system pharmacologically (Mednick et al. 2013). Zolpidem is one of the most frequently used drugs in this regard, binding to GABAA receptors at the same location as benzodiazepines, thereby acting as a GABAA receptor agonist (Lemmer 2007). Zolpidem increases the time spent in slow-wave sleep (SWS) and reduces the amount of rapid eye movement (REM) sleep (Kanno et al. 2000; Uchimura et al. 2006; Zhang et al. 2020). Zolpidem also increases the density and power of sleep spindles (Dijk et al. 2010; Lundahl et al. 2012; Mednick et al. 2013; Niknazar et al. 2015; Zhang et al. 2020) as well as the coupling of spindles to SO (Niknazar et al. 2015; Zhang et al. 2020), and it was further found to enhance declarative memory consolidation during sleep, with postsleep performance improvements being associated with higher spindle density and spindle power as well as with SO–spindle coupling (Kaestner et al. 2013; Mednick et al. 2013; Zhang et al. 2020).However, it remains unclear whether the changes in sleep stages, sleep spindles, and SO–spindle coupling after pharmacological manipulation with zolpidem are functionally related to the mechanisms underlying sleep-dependent memory consolidation such as memory reactivation. Over the last few years, targeted memory reactivation (TMR) has been increasingly applied to manipulate memory reactivation during sleep experimentally by presenting learning-associated reminder cues like odors or sounds (Oudiette and Paller 2013; Hu et al. 2020; Klinzing and Diekelmann 2020). TMR biases sleep-related neuronal replay events toward the reactivated memory contents (Lewis and Bendor 2019) and enhances subsequent recall performance (Rudoy et al. 2009; Diekelmann et al. 2011; Schreiner et al. 2015; Cairney et al. 2018). Although a few studies observed modulations of SOs (Rihm et al. 2014), sleep spindles (Cox et al. 2014), and SO–spindle coupling (Bar et al. 2020) with TMR during sleep, studies on the role of specific neurotransmitters and particularly on the role of GABAergic neurotransmission and associated changes in sleep oscillations for targeted memory reactivation are entirely lacking. One previous study tested the effect of pharmacologically increased GABAergic activity by administering the benzodiazepine clonazepam after cued reactivation of a declarative memory during wakefulness (Rodríguez et al. 2013). Clonazepam increased memory performance when it was administered after reactivation with an incomplete reminder cue, suggesting that increasing GABAergic neurotransmission may enhance the restabilization of reactivated declarative memories in humans during wakefulness.In the present study, we tested the effect of modulating GABAergic activity with zolpidem on targeted memory reactivation during sleep and associated changes in sleep spindles as well as SO–spindle and SO–theta coupling. We hypothesized that zolpidem enhances the beneficial effects of targeted memory reactivation on memory performance and that this enhancement is associated with increases in spindle density, spindle power, SO–spindle coupling, and possibly SO–theta coupling, and the amount of SWS. Participants were trained on a memory task including 30 sound–word associations in the evening (Forcato et al. 2020) and received an oral dose of 10 mg zolpidem (n = 11) or placebo (n = 11) after training before a full night of sleep in the sleep lab (Fig. 1). During the night, incomplete reminder cues (sounds + first syllable of the associated words) were played again via in-ear headphones during SWS. The next morning, participants were trained on an interference memory task to probe the stability of the original memory, which was tested 30 min later.Open in a separate windowFigure 1.Experimental design and memory task. (A) All subjects took part in a training session at ∼22.30, were administered with placebo (n = 11) or 10 mg of zolpidem (n = 11) before going to bed at 23:00, and received targeted memory reactivation during the first SWS period. After ∼8 h of sleep, in the morning, subjects learned an interference task and were tested on the original memory task in a testing session 30 min after the interference task. (B) Training: First, subjects were presented with 30 sound–word associations for learning. For each association, the sound was presented first for 2900 msec. The sound then continued accompanied by the word written on the screen and spoken aloud for 1500 msec. After a 4000-msec break, the next association was presented in the same way. After all associations were presented once, participants completed an immediate cued recall test. For each association, the sound was presented for 2900 msec. The sound then continued accompanied by the first syllable of the associated word for 1500 msec. Participants were then given 5000 msec to say the complete word aloud (sound continued during the entire period). Independently of their response, the correct answer was then presented on the screen and via headphones for 1500 msec. Reactivation: Each sound was first presented alone for an average of 2900 msec; the sound then continued accompanied by the first syllable of each word for another 1500 msec. After a 7000-msec break, the next sound–syllable pair was presented until all 30 pairs had been presented once. Testing: Each sound was presented for 500 msec and then the sound continued and subjects had 5000 msec to say the associated word aloud. After a break of 4000 msec, the procedure continued for the rest of the 30 associations. Adapted from Forcato et al. (2020).  相似文献   
47.
We examined the occurrence of faking on a rating situational judgment test (SJT) by comparing SJT scores and response styles of the same individuals across two naturally occurring situations. An SJT for medical school selection was administered twice to the same group of applicants (N = 317) under low‐stakes (T1) and high‐stakes (T2) circumstances. The SJT was scored using three different methods that were differentially affected by response tendencies. Applicants used significantly more extreme responding on T2 than T1. Faking (higher SJT score on T2) was only observed for scoring methods that controlled for response tendencies. Scoring methods that do not control for response tendencies introduce systematic error into the SJT score, which may lead to inaccurate conclusions about the existence of faking.  相似文献   
48.
Applied Research in Quality of Life - By 2015, 80% of the population in South America was living in urban areas. Although children in urban areas, on average, enjoy better conditions than children...  相似文献   
49.
Declarative memory consolidation: mechanisms acting during human sleep   总被引:10,自引:0,他引:10       下载免费PDF全文
Of late, an increasing number of studies have shown a strong relationship between sleep and memory. Here we summarize a series of our own studies in humans supporting a beneficial influence of slow-wave sleep (SWS) on declarative memory formation, and try to identify some mechanisms that might underlie this influence. Specifically, these experiments show that declarative memory benefits mainly from sleep periods dominated by SWS, whereas there is no consistent benefit of this memory from periods rich in rapid eye movement (REM) sleep. A main mechanism of declarative memory formation is believed to be the reactivation of newly acquired memory representations in hippocampal networks that stimulates a transfer and integration of these representations into neocortical neuronal networks. Consistent with this model, spindle activity and slow oscillation-related EEG coherence increase during early sleep after intense declarative learning in humans, signs that together point toward a neocortical reprocessing of the learned material. In addition, sleep seems to provide an optimal milieu for declarative memory reprocessing and consolidation by reducing cholinergic activation and the cortisol feedback to the hippocampus during SWS.  相似文献   
50.
Recent studies indicated a selective activation during rapid eye movement (REM) sleep of the amygdala known to play a decisive role in the processing of emotional stimuli. This study compared memory retention of emotional versus neutral text material over intervals covering either early sleep known to be dominated by nonREM slow wave sleep (SWS) or late sleep, in which REM sleep is dominant. Two groups of men were tested across 3-h periods of early and late sleep (sleep group) or corresponding retention intervals filled with wakefulness (wake group). Sleep was recorded polysomnographically. Cortisol concentrations in saliva were monitored at acquisition and retrieval testing. As expected, the amount of REM sleep was about three times greater during late than during early retention sleep, whereas a reversed pattern was observed for SWS distribution (P<0.001). Sleep improved retention, compared with the effects of wake intervals (P<0.02). However, this effect was substantial only in the late night (P<0.005), during which retention was generally worse than during the early night (P<0.02). Late sleep particularly enhanced memory for emotional texts. This effect was highly significant in comparison with memory for neutral texts (P<0.01) and in comparison with memory after late and early wake intervals (P<0.001). Cortisol concentration differed between early and late retention intervals but not between sleep and wake conditions. Results are consonant with a supportive function of REM sleep predominating late sleep for the formation of emotional memory in humans.  相似文献   
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