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1.
This study explored differences between homeless male veterans in metropolitan and micropolitan cities in Nebraska on sociodemographic, housing, clinical, and psychosocial characteristics as well as health service use. A convenience sample of 151 homeless male veterans (112 metropolitan, 39 micropolitan) were recruited from Veterans Affairs facilities and area shelters in Omaha, Lincoln, Grand Island, and Hastings in Nebraska. Research staff conducted structured interviews with homeless veterans. Results showed that compared to homeless veterans in metropolitans, those in micropolitans were more likely to be White, unmarried, living in transitional settings, and were far more transient but reported greater social support and housing satisfaction. Veterans in micropolitans also reported more medical problems, diagnoses of anxiety and personality disorders, and unexpectedly, were more likely to report using various health services and less travel time for services. Together, these findings suggest access to homeless and health services for veterans in micropolitan areas may be facilitated through Veterans Affairs facilities and community providers that work in close proximity to one another. Many homeless veterans in these areas are transient, making them a difficult population to study and serve. Innovative ways to provide outreach to homeless veterans in micropolitan and more rural areas are needed.  相似文献   
2.
Research has shown that sleep is beneficial for the long-term retention of memories. According to theories of memory consolidation, memories are gradually reorganized, becoming supported by widespread, distributed cortical networks, particularly during postencoding periods of sleep. However, the effects of sleep on the organization of memories in the hippocampus itself remains less clear. In a 3-d study, participants encoded separate lists of word–image pairs differing in their opportunity for sleep-dependent consolidation. Pairs were initially studied either before or after an overnight sleep period, and were then restudied in a functional magnetic resonance imaging (fMRI) scan session. We used multivariate pattern similarity analyses to examine fine-grained effects of consolidation on memory representations in the hippocampus. We provide evidence for a dissociation along the long axis of the hippocampus that emerges with consolidation, such that representational patterns for object–word memories initially formed prior to sleep become differentiated in anterior hippocampus and more similar, or overlapping, in posterior hippocampus. Differentiation in anterior hippocampal representations correlated with subsequent behavioral performance. Furthermore, representational overlap in posterior hippocampus correlated with the duration of intervening slow wave sleep. Together, these results demonstrate that sleep-dependent consolidation promotes the reorganization of memory traces along the long axis of the hippocampus.

The hippocampus has long been considered critical for encoding new memories; however, the effects of consolidation on hippocampal memory traces has remained an area of active research. Memories are thought to be stabilized for the long term as they become distributed across neocortical networks (Buzsáki 1989; Alvarez and Squire 1994; McClelland et al. 1995), a process supported by mechanisms during sleep (Diekelmann and Born 2010; Rasch and Born 2013). Whereas much research has been devoted to understanding the hippocampal contributions to the long-term retention of memories, open questions remain in considering how sleep-dependent consolidation affects the organization of hippocampal traces.The hippocampus has previously been shown to be critical for binding disparate elements of an experience together (Cohen and Eichenbaum 1993; Davachi 2006). Theories suggest that the hippocampus quickly encodes new experiences, while the cortex, with a slower learning rate, gradually comes to represent the central features from this hippocampal trace, resulting in abstracted memories that can be integrated into long-term cortical stores (McClelland et al. 1995). Prior research has demonstrated evidence for a coordinated hippocampal–cortical dialogue during sleep (Andrade et al. 2011; Bergmann et al. 2012; Ngo et al. 2020) as well as enhanced hippocampal–cortical functional connectivity after learning, facilitating the retention of memories (Tambini et al. 2010; Tompary et al. 2015; Murty et al. 2017; Cowan et al. 2021). Reports suggest consolidation results in more integrated cortical memory traces in the cortex (Richards et al. 2014; Tompary and Davachi 2017; Cowan et al. 2020); however, it remains an open question whether the active consolidation processes that support memory reorganization across hippocampal–cortical networks also transform hippocampal memory traces.Research on the fate of the hippocampal trace with consolidation has often focused on questions about the permanence of memories in the hippocampus. Theories of systems consolidation have classically debated whether the hippocampal trace is time-limited (Alvarez and Squire 1994), or, rather, whether the hippocampus continues to represent memories in perpetuity (Nadel and Moscovitch 1997; Winocur and Moscovitch 2011; Moscovitch et al. 2016; Sekeres et al. 2018a). Another theory posits that while the original hippocampal trace is transient, during retrieval the hippocampus reconstructs details of an experience from cortical traces (Barry and Maguire 2019). Much research in this vein has focused on investigating changes in hippocampal blood-oxygenation level-dependent (BOLD) univariate activation with time (Bosshardt et al. 2005a,b; Takashima et al. 2006, 2009; Gais et al. 2007; Sterpenich et al. 2007, 2009; Yamashita et al. 2009; Milton et al. 2011; Watanabe et al. 2012; Ritchey et al. 2015; Baran et al. 2016; Dandolo and Schwabe 2018) and the effects of hippocampal lesions in animals and humans (Winocur et al. 2001; Frankland and Bontempi 2005; Winocur and Moscovitch 2011; Moscovitch et al. 2016) with mixed results. Interestingly, pinpointing these effects along the long axis of the hippocampus has also proven unclear. Some reports have found that only the anterior hippocampus exhibits time-dependent changes in retrieval-related univariate activation, with evidence of decreases with delay (Takashima et al. 2006; Milton et al. 2011; Dandolo and Schwabe 2018), but also evidence of greater activation for more remote, compared with recent, memories (Bosshardt et al. 2005a,b). At the same time, other studies have found decreases in univariate activation only in the posterior hippocampus (Bosshardt et al. 2005b; Takashima et al. 2009; Yamashita et al. 2009; Milton et al. 2011; Watanabe et al. 2012; Ritchey et al. 2015; Sekeres et al. 2018b).Because of these conflicting findings, instead of asking just about dependence or overall changes in activation in the hippocampus, theories and empirical research have instead increasingly considered the organization of memory representations in the hippocampus (Robin and Moscovitch 2017; Sekeres et al. 2018a). Broadly, using representational similarity analyses, several studies have shown that hippocampal memory representations tend to become differentiated over learning, particularly for memories with overlapping content (LaRocque et al. 2013; Schlichting et al. 2015; Chanales et al. 2017; Brunec et al. 2020). Furthermore, it has been suggested that information is represented at different scales or “granularity” along the long axis of the hippocampus, in line with place field size differences (Kjelstrup et al. 2008; Komorowski et al. 2013), with anterior hippocampus representing more similar, coarse-grained, or gist-like information, while the posterior hippocampus represents fine-grained, detail-oriented representations (Evensmoen et al. 2013; Poppenk et al. 2013; Robin and Moscovitch 2017; Brunec et al. 2018, 2020). However, limited work has investigated whether this representational organization is altered with consolidation. Reports have shown that memory representations sharing overlapping content become more similar over a delay (Tompary and Davachi 2017; Audrain and McAndrews 2020), yet other work has found that hippocampal representations were not modulated by time (Ritchey et al. 2015; Ezzyat et al. 2018). Intriguingly, reports indicating greater differentiation in memories in anterior compared with posterior hippocampus with consolidation (Tompary and Davachi 2017; Dandolo and Schwabe 2018; Ezzyat et al. 2018) raise the possibility that the representational granularity along the anteroposterior axis may be transformed with consolidation. Thus, more work is needed to understand how consolidation influences the representational structure of memories in the hippocampus. In particular, despite much research connecting sleep to consolidation (Diekelmann and Born 2010; Rasch and Born 2013), it remains unknown whether sleep-dependent processes facilitate such delay-dependent transformations to the hippocampus.Active processes in the sleeping brain seem to be optimized for systems consolidation. Currently, the best mechanistic evidence for sleep-dependent consolidation comes from studies on hippocampal replay showing the repeated reactivation of encoding-related patterns of hippocampal activity (Buzsáki 1989; Wilson and McNaughton 1994; Girardeau and Zugaro 2011), which seems to be coordinated with replay in areas of the cortex (Ji and Wilson 2007; Peyrache et al. 2009; Wierzynski et al. 2009). It is thought that the coupling between oscillations during non-REM sleep stages (particularly slow wave sleep [SWS])—including sharp wave ripples that support replay, thalamocortical spindles, and slow oscillations—facilitates the hippocampal–cortical dialogue and information transfer to the cortex (Buzsáki 1996; Sirota et al. 2003; Steriade 2006; Clemens et al. 2011; Mölle and Born 2011; Staresina et al. 2015). Indeed, our previously published work from the present study provided supporting evidence that the density of thalamocortical sleep spindles (11–16 Hz) during overnight sleep is related to enhanced hippocampal–cortical functional connectivity measures, and increased similarity, or greater representational overlap, among memories in the ventromedial prefrontal cortex (vmPFC) (Cowan et al. 2020). Yet, while some prior work has shown that features of sleep, including spindle density and the duration of non-REM SWS, are related to decreased retrieval-related hippocampal activation for memoranda learned prior to sleep (Takashima et al. 2006; Baran et al. 2016; Hennies et al. 2016), it remains unclear how the reactivation of hippocampal traces during replay may impact the way memories are organized along the long axis of the hippocampus.To examine the effects of sleep-dependent consolidation on the neural representation of memories in the hippocampus, we designed a within-participant 3-d study using overnight polysomnography (PSG), functional magnetic resonance imaging (fMRI), and behavioral measures of memory (Fig. 1). In this study, aspects of which have been previously published (Cowan et al. 2020), participants first studied a list of word–image pairs before sleeping overnight (Sleep List), during which PSG was recorded. Upon waking in the morning, participants studied a new list of pairs (Morning List). The word–image pairs from these two lists were then restudied while undergoing an fMRI scan, intermixed with a third, novel list of pairs (Single Study List). Associative memory was tested immediately after the scan and again 24 h later. We compared measures of multivariate pattern similarity and univariate BOLD signal for the lists learned prior to, or after, sleep to probe how modulating the opportunity for sleep-dependent consolidation impacts the way memories are organized across the long axis of the hippocampus. Furthermore, our design allowed us to examine how features of overnight sleep are related to the representational organization of memories learned prior to the sleep period, as well as the behavioral benefit of changes to the organization of these memories. Thus, our study provides a novel examination of the effects of sleep-dependent consolidation on the representation of memories along the long axis of the hippocampus.Open in a separate windowFigure 1.Study design. For all encoding and restudy sessions, participants were asked to form an association between a word and an image. Participants first encoded the Sleep List (blue) before sleeping overnight while polysomnography was recorded. The next morning (day 2), participants encoded a second set of novel word–image pairs (Morning List). After a short delay (∼2 h), participants restudied these two sets of pairs, intermixed with novel pairs (Single Study List) in the functional magnetic resonance imaging (fMRI) scanner. Source memory was tested immediately after the scan and after a 24-h delay (day 3).  相似文献   
3.
The purpose of the present study was to examine heart rate (HR) and affective reactions to state self-objectification as a function of gender. We examined negative affect, positive affect, guilt, and HR at 6-second and 5-minute intervals across baseline, control, high objectification, low objectification, and cologne conditions in men (n = 53) and women (n = 57). Mixed factorial MANOVA results indicated a statistically significant Gender × Condition interaction. Both men and women showed a cardiac orienting response to high versus low objectification. Cardiac stress reactions to objectification were higher among women. Negative affective reactions to objectification were more pervasive across conditions among women.  相似文献   
4.
Patients infected with chronic hepatitis C virus (HCV) commonly suffer from the triad of depression, pain and fatigue. This symptom triad in HCV is likely influenced by additional psychological and interpersonal factors, although the relationship is not clearly understood. This retrospective study aimed to characterize the relationship between attachment style and depressive and physical symptoms in the HCV-infected population. Over 18 months, 99 consecutively referred HCV infected patients were assessed with the Hamilton Depression Rating Scale (HDRS), Fatigue Severity Scale, Patient Health Questionnaire-15 for physical symptoms and the Relationship Questionnaire for attachment style. An ANOVA was used to identify differences between attachment styles and Pearson correlations were used to evaluate the association between depression, fatigue and physical symptoms. Approximately 15 % of patients in the sample had a fearful attachment style. Patients with fearful attachment style had significantly higher depressive symptoms compared to a secure attachment style (p = .025). No differences in physical and fatigue symptoms were observed between attachment styles. Further, HDRS scores were significantly associated with fatigue scores (p < .001) and physical symptoms (p < .001), reinforcing the relationship between these symptom domains in HCV-infected patients. Although depressive, physical and fatigue symptoms are inter-related in HCV-infected patients, our study results suggest that only depressive symptoms were influenced by the extremes of attachment style. Screening of relationship styles may identify at-risk HCV-infected individuals for depression who may have difficulty engaging in care and managing physical symptoms.  相似文献   
5.
According to a social rank hypothesis, consumers who live in regions with higher income inequality will show greater interest in, and attention toward, positional goods and high‐status brands that serve a social signaling role. We analyze millions of posts on the microblogging platform Twitter for mentions of high‐ and low‐status brands. We find that luxury brands such as “Louis Vuitton” and “Rolex” are more frequently mentioned in tweets originating from US states, counties, and major metropolitan areas with higher levels of income inequality. In contrast, mentions of everyday brands such as “Walmart” or “Kmart” are more frequent in regions with a more equal distribution of income. Using sentiment analysis, we find higher valence (positivity) and arousal (excitement) for tweets that both mention high‐status brands and originate from regions with high levels of income inequality. These results corroborate the social rank hypothesis, showing that more psychological resources are allocated to positional consumption when the income gap between the rich and the poor is larger.  相似文献   
6.
The medical records of 110 patients receiving conventional antipsychotics at two geographically distinct Veterans Administration hospitals (Syracuse, New York, and Omaha, Nebraska) were reviewed. The most common reasons for continuation of conventional antipsychotics were good response and patient or physician choice. Frequently, physicians did not discuss the reasons for continuing conventional antipsychotics or the availability of alternative therapies with their patients. Geographic differences in physicians' prescribing practices of conventional antipsychotics were apparent.  相似文献   
7.
8.
Understanding influence on and effects of retesting is important to the selection practitioner. This article examines retesting effects on a series of selection measures for mechanically related positions to extend research that has been conducted in more controlled environments. While validity was not significantly different on retesting, time between test attempts and score increase on Spatial Reasoning were positively related, indicating the possibility of learning effects. Lower score increases were found for highly g‐loaded measures, and individuals who showed an increase scored more highly on average on their first attempt. Men tended to increase their scores more than women. We close with a discussion of the practical implications of our findings and how to build on them with future research.  相似文献   
9.
High-level judgement and decision-making tasks display dynamic bidirectional relationships in which salient cues determine how responses are evaluated by decision-makers, and these responses in turn determine the cues that are considered. In this paper, we propose Kosko's bidirectional associative memory (BAM) network, a minimal two-layer recurrent neural network, as a mathematically tractable toy model with which the properties of existing bidirectional models, and the behavioural implications of these properties, can be studied. We first derive results regarding the dynamics of the BAM network, and then show how these results can be used to provide an analytically sound explanation for a number of important findings, including coherence shifts in judgement and choice, anchoring effects, and reference point effects.  相似文献   
10.
The present work investigated the prevalence and spectrum of psychopathology in children with thalassemia. Childhood psychopathology measurement schedule (CPMS), adapted from Child Behavior Checklist was administered on children with thalassemia major receiving regular blood transfusion. Age and sex matched children with other chronic illness (bronchial asthma) served as controls. 46.7% of children with thalassemia had a CPMS score of > 10 as against 17.1% in the control group. Children with thalassemia had higher scores in factors of conduct problems, special symptoms and somatization. This study highlights the significantly higher psychopathology in children with thalassemia major and emphasizes the need for psychosocial support during treatment.  相似文献   
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