A brief nap is beneficial for human route-learning: The role of navigation experience and EEG spectral power

Here, we examined the effect of a daytime nap on changes in virtual maze performance across a single day. Participants either took a short nap or remained awake following training on a virtual maze task. Post-training sleep provided a clear performance benefit at later retest, but only for those participants with prior experience navigating in a three-dimensional (3D) environment. Performance improvements in experienced players were correlated with delta-rich stage 2 sleep. Complementing observations that learning-related brain activity is reiterated during post-navigation NREM sleep in rodents, the present data demonstrate that NREM sleep confers a performance advantage for spatial memory in humans.A growing body of animal and human literature suggests that the consolidation of memories occurs optimally during periods of post-learning sleep. Nonrapid eye movement sleep (NREM), in particular, may be beneficial for the offline consolidation of hippocampus-dependent learning. The neurophysiological basis for this hypothesis is derived largely from electrophysiological studies in rodents, demonstrating that patterns of hippocampal place cell activity first seen during waking exploration are later reexpressed during post-learning sleep (Wilson and McNaughton 1994; Kudrimoti et al. 1999; Nadasdy et al. 1999; Ji and Wilson 2007). Behavioral studies in humans meanwhile demonstrate that NREM sleep is beneficial for declarative memory performance, relative to equivalent periods of wakefulness (Plihal and Born 1997; Tucker et al. 2006). However, the memory tasks typically employed in human research are quite different from those used in rodents, with human studies most often focusing on the memorization of verbal or visual stimuli (Plihal and Born 1997; Schabus et al. 2004; Clemens et al. 2005; Ellenbogen et al. 2006; Tucker et al. 2006; Daurat et al. 2008). Thus far, sleep-dependent memory reactivation has not been established to be directly beneficial for memory performance in an animal model, as the protocols employed in this research typically involve well-learned simple tasks which do not easily lend themselves to measurement of learning across time (Wilson and McNaughton 1994; Kudrimoti et al. 1999). Although the hippocampal memory reactivation described in rodents is a possible explanation for the effect of NREM sleep on human declarative memory, widely divergent methodologies employed across species prohibit confidence in this conclusion.Bridging this conceptual gap, a small handful of studies have begun to explore the relationship between spatial navigation and NREM sleep in humans. Notably, a PET study by Peigneux et al. (2004) demonstrated that learning-related hippocampal activity seen while training on a virtual maze task is again expressed during post-learning human sleep. Furthermore, this hippocampal reactivation strongly predicted overnight improvement on the task (Peigneux et al. 2004). Additional studies have suggested a link between sleep and other types of spatial-related learning, including mental rotation performance (Plihal and Born 1999), the ability to reproduce a complex figure (Clemens et al. 2006; Tucker and Fishbein 2008), performance on a computerized version of Milner''s (1965) “bolt head” maze (Tucker and Fishbein 2008), and memory for the location of verbal information on a screen (Daurat et al. 2008).Yet it remains unclear whether sleep, relative to wakefulness, provides a performance benefit for human route-learning in the context of a realistic spatial environment. Navigation through virtual environments is a strongly hippocampus-dependent task (Peigneux et al. 2004; Astur et al. 2005) and provides an experimental model closely paralleling the spatial exploration tasks employed in the rodent literature. However, the few studies reporting effects of sleep on human navigation performance have been contradictory. Using a navigation task similar to that of Peingeux et al. (2004), Orban et al. (2006) failed to detect any effect of post-learning sleep deprivation on maze performance but did find evidence of altered task-related brain activity, concluding that sleep supports “covert” memory reorganization (Orban et al. 2006). In direct contrast, Ferrara et al. found that spatial memory is improved when a retention interval falls across a night of sleep, relative to when route memory must be retained during daytime wakefulness, or across a night of sleep deprivation (Ferrara et al. 2006, 2008).The present study clarifies these issues by examining the effect of a post-learning nap on complex route-learning in a three-dimensional (3D) virtual environment. When controls are tested at a different time of day than sleep participants, circadian confounds may present a substantial problem. Alternatively, overnight protocols employing sleep-deprived subjects necessarily suffer from confounds related to this sleep deprivation during the retention interval. The use of a daytime nap as a sleep intervention avoids these pitfalls by allowing all subjects to be trained and tested at the same circadian time, and in the absence of sleep deprivation. A series of recent studies confirm that a daytime nap is sufficient to induce performance improvements on declarative and procedural memory tasks, relative to wake subjects (Mednick et al. 2003; Backhaus and Junghanns 2006; Nishida and Walker 2006; Tucker et al. 2006; Lahl et al. 2008; Tucker and Fishbein 2008).Participants (n = 53, 34 female) were trained on a virtual maze-learning task at 12:30 pm. Following training, nap participants lay down for a 1.5-h sleep opportunity. These subjects were allowed to obtain as much NREM sleep as possible but were awoken at the first signs of REM (see Table 

Philosophical Aspects of Dual Use Technologies

The term dual use technologies refers to research and technology with the potential both to yield valuable scientific knowledge and to be used for nefarious purposes with serious consequences for public health or the environment. There are two main approaches to assessing dual use technologies: pragmatic and metaphysical. A pragmatic approach relies on ethical principles and norms to generate specific guidance and policy for dual use technologies. A metaphysical approach exhorts us to the deeper study of human nature, our intentions, goals, values ideals and social relations when considering dual use technology. Use of science and technology (S and T) is determined by two components of human nature: human intentions and choices. We have drawn a distinction between specific measures, goals and intentions with respect to technologies in order to show that moral judgment about technologies must precede their use. Understanding of our intentionality and values, and our moral ideals, as a measurable, tangible part of the real world is important for the prevention of any possible harm from S and T. In the context of dual use technologies, we stress the importance of three main understandings of human nature: vulnerability, responsibility and narrative identity. These can become a strong ontological “antidote” to technology’s poisoning of modern man. Each new technology can be measured and compared with man’s values, traditions and societal norms. This can be done bearing in mind the concept that human nature is not dualistic, but pluralistic. A system of ethical principles that includes the principles of good intentions, the correspondence of goals and means, the balancing of risks and benefits, simplicity, and contextuality, will help ensure that technologies are more humanistic and friendly to human beings.     

Should we screen for depression? Caveats and potential pitfalls

The availability of brief screening instruments encourages their routine use in identifying individuals who are presumed to be at risk for clinical depression. In primary medical care where this idea has been most tested, however, there is little evidence that screening by itself improves the outcome of depression. Reasons why screening cannot serve as an efficient basis for the prevention of depression are reviewed. Moreover, a positive score on a screening instrument does not indicate a clear need for intervention or the form that any intervention should take. Routine screening should be undertaken only when the resources are available for interpreting the significance of positive screen scores, appropriate and acceptable interventions are available, and potential negative effects of screening can be avoided. Until these conditions can be met, alternatives to screening should be considered.     

The Long and Winding Road: An Autobiographic Study of an Elite Athlete Mother’s Journey to Winning Gold

Within sport psychology, researchers have explored elite athlete mothers’ experiences. More work is needed to understand the nuanced psychosocial aspects of their athletic journeys. Studying autobiographical narratives is useful toward understanding the psychosocial nuances of motherhood and athletics in sociocultural context. Within the present study we sought to extend this understanding through studying one elite athlete’s—British runner Jo Pavey—journey as an athlete mother within her autobiography This Mum Runs (26 chapters totaling 253 pages). Thematic narrative analysis of key chapters focusing on pregnancy and motherhood in relation to training and competition allowed for the identification of a central theme—discovery narrative–reconfiguring the performance narrative—along with two subthemes: go with the flow and best of both worlds. The subthemes are used to illustrate the navigation of tensions in relation to an athlete mother identity grounded in family relationships to facilitate training and competition goals, within a discovery narrative. Applied sport psychology recommendations are made using narrative theory in relation to key findings. Recommendations focused on athlete stories and narrative resources as concrete entry points to encourage compatible athlete mother identities and sport career engagement. This study adds to sport psychology work that has used autobiography as theoretical, analytical, and applied resources to expand understanding of marginalized and/or hard to access topics in elite sport. This is the first autobiographic study to focus on elite athlete mother identities, furthering understanding of nuanced identity negotiation and experiences over time.

Lay Summary: Understanding of elite athlete mother's negotiation of identity and athletic career is expanded through studying published/public autobiographical narratives. A discovery narrative grounded in personal growth and family relationships facilitates strategies that facilitate training and competition goals.     

Fabry Disease Practice Guidelines: Recommendations of the National Society of Genetic Counselors

Identification and comprehensive care of individuals who have Fabry disease (FD) requires a multidisciplinary approach inclusive of genetic testing, test interpretation, genetic counseling, long term disease symptom monitoring, treatment recommendations, and coordination of therapy. The purpose of this document is to provide health care professionals with guidelines for testing, care coordination, identification of psychosocial issues, and to facilitate a better understanding of disease treatment expert recommendations for patients with Fabry disease. These recommendations are the opinions of a multicenter working group of genetic counselors, medical geneticists, and other health professionals with expertise in Fabry disease counseling, as well as representatives/founders of the two United States based Fabry disease patient advocacy groups who are themselves affected by Fabry disease. The recommendations are U.S. Preventive Task Force Class III, and they are based on clinical experience, a review of pertinent English-language articles, and reports of expert committees. This document reviews the genetics of Fabry disease, the indications for genetic testing, interpretation of results, psychosocial considerations, and references to professional and patient resources.