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Quantum coherence is a crucial resource in numerous quantum processing tasks. The robustness of coherence provides an operational measure of quantum coherence, which can be calculated for various states using semidefinite programming. However, this method depends on convex optimization and can be time-intensive, especially as the dimensionality of the space increases. In this study, we employ machine learning techniques to quantify quantum coherence, focusing on the robustness of coherence. By leveraging artificial neural networks, we developed and trained models for systems with different dimensionalities. Testing on data samples shows that our approach substantially reduces computation time while maintaining strong generalizability.

Abstract Reinforcement learning (RL) models have been influential in characterizing human learning and decision making, but few studies apply them to characterizing human spatial navigation and even fewer systematically compare RL models under different navigation requirements. Because RL can characterize one’s learning strategies quantitatively and in a continuous manner, and one’s consistency of using such strategies, it can provide a novel and important perspective for understanding the marked individual differences in human navigation and disentangle navigation strategies from navigation performance. One-hundred and fourteen participants completed wayfinding tasks in a virtual environment where different phases manipulated navigation requirements. We compared performance of five RL models (3 model-free, 1 model-based and 1 “hybrid”) at fitting navigation behaviors in different phases. Supporting implications from prior literature, the hybrid model provided the best fit regardless of navigation requirements, suggesting the majority of participants rely on a blend of model-free (route-following) and model-based (cognitive mapping) learning in such navigation scenarios. Furthermore, consistent with a key prediction, there was a correlation in the hybrid model between the weight on model-based learning (i.e., navigation strategy) and the navigator’s exploration vs. exploitation tendency (i.e., consistency of using such navigation strategy), which was modulated by navigation task requirements. Together, we not only show how computational findings from RL align with the spatial navigation literature, but also reveal how the relationship between navigation strategy and a person’s consistency using such strategies changes as navigation requirements change.

Abstract Introduction We and collaborators discovered that flickering lights and sound at gamma frequency (40 Hz) reduce Alzheimer's disease (AD) pathology and alter immune cells and signaling in mice. To determine the feasibility of this intervention in humans we tested the safety, tolerability, and daily adherence to extended audiovisual gamma flicker stimulation. Methods Ten patients with mild cognitive impairment due to underlying AD received 1‐hour daily gamma flicker using audiovisual stimulation for 4 or 8 weeks at home with a delayed start design. Results Gamma flicker was safe, tolerable, and adherable. Participants’ neural activity entrained to stimulation. Magnetic resonance imaging and cerebral spinal fluid proteomics show preliminary evidence that prolonged flicker affects neural networks and immune factors in the nervous system. Discussion These findings show that prolonged gamma sensory flicker is safe, tolerable, and feasible with preliminary indications of immune and network effects, supporting further study of gamma stimulation in AD.

Previous studies showed that people could use either an egocentric or allocentric reference frame in spatial updating with body-based cues (i.e., physical body movements), but the adopted reference frame was anchored by the physical egocentric front when body-based cues were constrained. A recent study (He et al., 2018) showed that even without body-based cues, the orientation participants initially faced in the virtual environment (VE; initial heading) could be used to establish a reference frame, suggesting that the physical egocentric front could be overridden by a virtual orientation. In the current project, we aimed to: (a) replicate He et al.’s (2018) finding; (b) examine when the reference frame defined by the virtual initial heading was established; and (c) investigate the cognitive processes in establishing the initial heading as a reference frame. In four experiments, we were able to replicate the previous findings and found that the reference frame defined by the initial heading was established during spatial updating. More importantly, the reference frame defined by the initial heading was egocentric and participants did not need to know the orientation of their initial heading at the beginning of spatial updating to be able to use it. We discuss the cognitive processes of reference frame selection in spatial updating when body-based cues are absent.

Valued-based decision-making has been studied for decades in myriad topics such as consumer spending and gambling, but very rarely in spatial navigation despite the link between the two being highly relevant to survival. Furthermore, how people integrate episodic memories, and what factors are related to the extent of memory integration in value-based decision-making, remain largely unknown. In the current study, participants learned locations of various objects in a virtual environment and then decided whether to reach goal objects from familiar starting locations or unpredictable ones, with different penalties associated with each option. We developed computational models to test whether, when given an object to find, participants' starting location decisions reflected their past performance specific to that goal (Target-specific model) or integrated memory from performance with all goals in the environment (Target-common model). Because participants' wayfinding performance improved throughout the experiment, we were able to examine what factors related to the generalization of past experience. We found that most participants' decisions were better fit by the Target-common model, and for the people whose decisions were better fit by the Target-common model this integrative tendency may be tied to their concurrently greater performance variability with individual targets. Moreover, greater success on our task was predicted by an interaction between the ability to estimate probabilities relevant to decision-making and self-report general task ability. Collectively, our results show how related navigational episodic memories can be reflected in decision-making, and uncover individual differences contributing to such processes. [ABSTRACT FROM AUTHOR]

This article takes the political campaign against The life of Wu Xun (Wu Xun zhuan, 1950), launched by Mao Zedong in 1951, as a point of departure to explore the intertwining relationship between cinema and the new historiography in post-1949 China. While the criticisms of The life of Wu Xun highlighted the central role of peasant warfare in imperial Chinese history and thereby resulted in the growing popularity of the class view in Chinese historiography, the making of two other films set in the Qing dynasty, Song Jingshi (1955) and Lin Zexu (1959), attested to a tension between two historiographical trends in Mao's China: the class view and historicism. This article argues that the entanglement of historians and non-historians, including filmmakers, allowed for the making of a history-centred public space of communication for both historians and laypersons alike to resort to China's past to make sense of the present and even attack Mao. Second, such a mode of history-qua-political discussion and polemic paved the way for the outbreak of the Cultural Revolution. In the mid-1960s, the tension between two historiographical trends would finally lead to the purge of historical researchers, filmmakers, writers and dramatists during the Cultural Revolution. [ABSTRACT FROM AUTHOR]

A substantial amount of research has been conducted to uncover factors underlying the pronounced individual differences in spatial navigation. Spatial working memory capacity (SWM) is shown to be one important factor. In other domains such as reading comprehension, the role of working memory capacity in task performance differences depends on the difficulty of other task demands. In the current study, we investigated whether, similarly, the relationship between SWM and spatial performance was dependent on the difficulty of spatial information integration in the environment. Based on our prior work, spatial information integration difficulty depends on (a) difficulty in observing spatial relationships between locations of interest in the environment and (b) the individual's ability to integrate such relationships. Leveraging virtual reality, we manipulated the difficulty in observing the spatial relationships during learning by changing the visibility of the buildings, and measured individual's self-report sense of direction (SOD) which modulates the ability to integrate such relationships under different degrees of visibility. We consistently found that in the "easy" spatial integration condition (high SOD with high visibility), high SWM did not significantly improve spatial learning. The same pattern was observed in the difficult condition (low SOD with low visibility). On the other hand, high SWM improved spatial learning for medium difficulty (high SOD with low visibility, or vice versa). Together, our results reveal that the role of SWM in spatial learning differences depends on spatial integration difficulty. Our results also have significant applied implications for using virtual reality to target and facilitate spatial learning. [ABSTRACT FROM AUTHOR]

In the current study, we investigated the ways in which the acquisition and transfer of spatial knowledge were affected by (a) the type of spatial relations predominately experienced during learning (routes determined by walkways vs. straight-line paths between locations); (b) environmental complexity; and (c) the availability of rotational body-based information. Participants learned the layout of a virtual shopping mall by repeatedly searching for target storefronts located in 1 of the buildings. We created 2 novel learning conditions to encourage participants to use either route knowledge (paths on walkways between buildings) or survey knowledge (straight-line distances and directions from storefront to storefront) to find the target, and measured the development of route and survey knowledge in both learning conditions. Environmental complexity was manipulated by varying the alignment of the buildings with the enclosure, and the visibility within space. Body-based information was manipulated by having participants perform the experiment in front of a computer monitor or using a head-mounted display. After navigation, participants pointed to various storefronts from a fixed position and orientation. Results showed that the frequently used spatial knowledge could be developed similarly across environments with different complexities, but the infrequently used spatial knowledge was less developed in the complex environment. Furthermore, rotational body-based information facilitated spatial learning under certain conditions. Our results suggest that path integration may play an important role in spatial knowledge transfer, both from route to survey knowledge (cognitive map construction), and from survey to route knowledge (using cognitive map to guide wayfinding). [ABSTRACT FROM AUTHOR]

The article talks about the reforming of the Chinese newspaper "Dagong bao" by its editor-in-chief Hu Zhengzhi and discusses the dynamism for reform and progress displayed by Dagong bao despite being controlled by Chinese warlords.