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Abstract Magnetization measurements in La2-xSrxCuO4 (LSCO) crystals indicate vortex order-disorder transition manifested by a sharp kink in the second magnetization peak. The transition field exhibits unique temperature dependence, namely a strong decrease with temperature in the entire measured range. This behavior rules out the conventional interpretation of a disorder-driven transition into an entangled vortex solid phase. We argue that the transition in LSCO is driven by both thermally- and disorder-induced fluctuations. The resulting “pinned liquid” disordered state is characterized by large thermal fluctuations and irreversible magnetic behavior. We extend these results and postulate that melting, solid-solid, and solid to pinned liquid transitions, are special cases of a unified order-disorder phase transition driven by both thermally- and disorder-induced fluctuations. The temperature dependence of the transition line and the nature of the disordered phase (solid, liquid, or pinned liquid) are determined by the relative contributions of these fluctuations and by the pinning mechanism. By varying the pinning mechanism and the pinning strength one obtains a spectrum of transition lines. In order to test our numerical results we present studies on a series of irradiated LSCO crystals, and show that increase of pinning, causes a depression of the transition line as well as a decrease in the curvature as the transition line, in agreement with our calculations. [ABSTRACT FROM AUTHOR]

Finite element method (FEM) analysis is employed to study and compare AC losses in a wide frequency range in two MgB2 superconducting wires in self-field and in the presence of external AC field. The modelled wires, of the same external dimensions, are mono- and 36-superconducting filaments embedded in either magnetic Monel or a nonmagnetic metallic wire sheath. We demonstrate that in a multifilamentary wire in self-field the Monel sheath serves as a ‘pole piece’ at the filament outer surface and alters local magnetic fields, current flow and AC losses distribution within the filament. In comparison with the nonmagnetic sheath with the same electrical conductivity, AC current in the wire with the magnetic sheath penetrates significantly deeper into the filaments and AC losses in the filament and in the magnetic sheath increase significantly. In contrast, the symmetry of the monofilament wire makes the current and loss distributions in the filament practically indifferent to the sheath composition. Still, losses in the magnetic sheath are much higher than in the nonmagnetic sheath due to increased flux dynamics. The application of DC current, on which the AC current is superimposed, sharply reduces the AC losses in the magnetic sheath material due to the drop in its permeability. Filament losses are also reduced in the presence of DC current, but to a much lesser extent. Results also show that in the kHz frequency range, the magnetic permeability of the sheath increases the skin effect in both the wire and filaments complex. As a result, at such frequencies, a significant portion of the current is carried by the metallic part of the wire instead of the superconductor, contributing to a further increase in losses. The analysis also shows that in the presence of external AC magnetic field, the Monel can provide magnetic shielding for inner filaments, thus reducing coupling effects between filaments. However, if magnetically saturated by the DC current, the Monel behaves quite similarly to a nonmagnetic sheath. [ABSTRACT FROM AUTHOR]

Magneto-optical imaging of dendritic flux instability is reported for NbN films exposed to magnetic fields ramped at a fast rate (0.1–3.2 kT s−1). The results show that as the magnetic ramp rate increases, the temperature and field range of the instability extends significantly. In particular, the lower and upper threshold fields ( and respectively) that bound the field range for dendritic instability are affected. The upper field is found to increase linearly with the applied field sweep rate, a behavior which is discussed in terms of a recent theoretical work (Vestgarden et al 2016 Phys. Rev. B 73 174511). The extended instability range should be taken into account in applications in which the superconducting films are exposed to rapid changes in the magnetic field. [ABSTRACT FROM AUTHOR]

Magnetic flux instability limits potential applications of superconductors such as MgB2 in practical devices. Previous studies in MgB2 films exposed to magnetic fields revealed the occurrence of dendritic flux avalanches at temperatures below T ∼ 10 K. In the present work it is shown that films of MgB2 exposed to a fast-ramped magnetic field display a dendritic flux instability at elevated temperatures, up to 23 K. Such instability can therefore cause malfunctioning of practical devices based on MgB2 films even when operating at liquid hydrogen temperature. [ABSTRACT FROM AUTHOR]

One of the richest and most powerful tools in social communication is the face. Facial expressions are a prominent way to convey high-dimensional, dynamic information, such as emotion, motivation, and intentions. Previous research has linked mimicry of facial expressions to positive human interaction (e.g., mutual agreement). In this study, we investigated in a real-world setting whether the mimicry pattern of multiple affective facial expressions depends on the interpersonal attitudinal agreement between interlocutors. We analyzed video clips of Democratic or Republican American politicians being interviewed by either a political ally or an opponent ( N total = 150 videos). The interviews showed either agreement between two Republicans or two Democrats, or disagreement between members of each affiliation. Using image processing tools, we extracted the intensity of the facial action units for each timepoint. In contrast to the prevalent notion that positive social interaction, such as agreement, fosters mimicry, we found mimicry of all facial expressions in both agreement and disagreement. Moreover, the pattern of the facial expressions mimicry depended on the agreement condition such that an artificial classifier could successfully discriminate between the agreement conditions. Our results suggest that not only positive interpersonal communication is characterized by mimicry but also negative one. This implies that in real-life interactions, mimicry may be a tool to understand others and thus successfully communicate, regardless of the positivity of the social interaction. Whereas the existence of mimicry may be indispensable for social communication, the specific pattern of facial expressions mimicry depends on the social context. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

We present a method for improving the performance of microwave coplanar resonators in magnetic fields, by using narrow superconducting strips of width close to the London penetration depth. In a range of low fields, the narrow strips inhibit the presence of magnetic vortices, thus preventing the generation of losses caused by their motion, leading to enhanced resistance to magnetic fields. Our method provides a more straightforward solution compared to previously proposed techniques designed to restrict vortex motion, holding potential for the development of improved devices based on microwave resonators., (© 2024. The Author(s).)

We present a MgB 2 -based Microwave Kinetic Inductance Detector (MKID) featuring a quality factor Q i ~ 10 5 and noise equivalent power NEP ~ 10 -14 W/Hz at 2 K. In comparison to YBCO-based MKIDs, the MgB 2 detector shows greater sensitivity to both temperature and magnetic field, a result of its two-gap nature and relatively low critical Hc2 field. Our data indicate that MgB 2 is more advantageous for MKID applications at temperatures lower than 3 K.

Our ability to identify an object is often impaired by the presence of preceding and/or succeeding task-irrelevant items. Understanding this temporal interference is critical for any theoretical account of interference across time and for minimizing its detrimental effects. Therefore, we used the same sequences of 3 orientation items, orientation estimation task, and computational models, to examine temporal interference over both short (<150 ms; visual masking) and long (175-475 ms; temporal crowding) intervals. We further examined how inter-item similarity modifies these different instances of temporal interference. Qualitatively different results emerged for interference of different scales. Interference over long intervals mainly degraded the precision of the target encoding while interference over short intervals mainly affected the signal-to-noise ratio. Although both interference instances modulated substitution errors (reporting a wrong item) and were alleviated with dissimilar items, their characteristics were markedly disparate. These findings suggest that different mechanisms mediate temporal interference of different scales., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 Hochmitz, Abu-Akel and Yeshurun.)

The reward system was shown to be involved in a wide array of processes. Nevertheless, the exploration of the involvement of the reward system during language processing has not yet been directly tested. We investigated the role of reward-processing regions while listening to a natural story. We utilized a published dataset in which half of the participants listened to a natural story and the others listened to a scrambled version of it to compare the functional MRI signals in the reward system between these conditions and discovered a distinct pattern between conditions. This suggests that the reward system is activated during the comprehension of natural stories. We also show evidence that the fMRI signals in reward-related areas might potentially correlate with the predictability level of processed sentences. Further research is needed to determine the nature of the involvement and the way the activity interacts with various aspects of the sentences., Competing Interests: The authors declare no competing interests., (© 2024 The Authors.)

This study examined whether temporal crowding-the impaired object identification when distracting objects precede and succeed it-occurs at the fovea and if so whether its magnitude is reduced. We presented a central sequence of three oriented items separated by relatively long intervals (200/400 ms) and used an orientation estimation task with mixture-model analyses. We found clear evidence of temporal crowding with central vision, even with 400 ms intervals. Critically, reduced encoding precision surfaced as a robust and unique characteristic of temporal crowding. The magnitude of central and peripheral temporal crowding was similar suggesting the involvement of higher visual areas. Precision impairment emerged even when only the target contained orientation information, excluding "response competition" as the sole interference mechanism; yet it was larger when all items included orientation information, underscoring the importance of orientation-selective mechanisms. Overall, we show that even with central simple stimuli, the formation of a stable visual representation is surprisingly slow. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Infant stimuli elicit widespread neural and behavioral response in human adults, and such massive allocation of resources attests to the evolutionary significance of the primary attachment. Here, we examined whether attachment reminders also trigger cross-brain concordance and generate greater neural uniformity, as indicated by intersubject correlation. Human mothers were imaged twice in oxytocin/placebo administration design, and stimuli included four ecological videos of a standard unfamiliar mother and infant: two infant/mother alone ( Alone ) and two mother-infant dyadic contexts ( Social ). Theory-driven analysis measured cross-brain synchrony in preregistered nodes of the parental caregiving network (PCN), which integrates subcortical structures underpinning mammalian mothering with cortical areas implicated in simulation, mentalization, and emotion regulation, and data-driven analysis assessed brain-wide concordance using whole-brain parcellation. Results demonstrated widespread cross-brain synchrony in both the PCN and across the neuroaxis, from primary sensory/somatosensory areas, through insular-cingulate regions, to temporal and prefrontal cortices. The Social context yielded significantly more cross-brain concordance, with PCNs striatum, parahippocampal gyrus, superior temporal sulcus, ACC, and PFC displaying cross-brain synchrony only to mother-infant social cues. Moment-by-moment fluctuations in mother-infant social synchrony, ranging from episodes of low synchrony to tightly coordinated positive bouts, were tracked online by cross-brain concordance in the preregistered ACC. Findings indicate that social attachment stimuli, representing evolutionary-salient universal cues that require no verbal narrative, trigger substantial interbrain concordance and suggest that the mother-infant bond, an icon standing at the heart of human civilization, may function to glue brains into a unified experience and bind humans into social groups. SIGNIFICANCE STATEMENT Infant stimuli elicit widespread neural response in human adults, attesting to their evolutionary significance, but do they also trigger cross-brain concordance and induce neural uniformity among perceivers? We measured cross-brain synchrony to ecological mother-infant videos. We used theory-driven analysis, measuring cross-brain concordance in the parenting network, and data-driven analysis, assessing brain-wide concordance using whole-brain parcellation. Attachment cues triggered widespread cross-brain concordance in both the parenting network and across the neuroaxis. Moment-by-moment fluctuations in behavioral synchrony were tracked online by cross-brain variability in ACC. Attachment reminders bind humans' brains into a unitary experience and stimuli characterized by social synchrony enhance neural similarity among participants, describing one mechanism by which attachment bonds provide the neural template for the consolidation of social groups., (Copyright © 2023 Shimon-Raz et al.)

We can all agree that a good story engages us, however, agreeing which story is good is far more debatable. In this study, we explored whether engagement with a narrative synchronizes listeners' brain responses, by examining individual differences in engagement to the same story. To do so, we pre-registered and re-analyzed a previously collected dataset by Chang et al. (2021) of functional Magnetic Resonance Imaging (fMRI) scans of 25 participants who listened to a one-hour story and answered questionnaires. We assessed the degree of their overall engagement with the story and their engagement with the main characters. The questionnaires revealed individual differences in engagement with the story, as well as different valence towards specific characters. Neuroimaging data showed that the auditory cortex, the default mode network (DMN) and language regions were involved in processing the story. Increased engagement with the story was correlated with increased neural synchronization within regions in the DMN (especially the medial prefrontal cortex), as well as regions outside the DMN such as the dorso-lateral prefrontal cortex and the reward system. Interestingly, positively and negatively engaging characters elicited different patterns of neural synchronization. Finally, engagement increased functional connectivity within and between the DMN, the ventral attention network and the control network. Taken together, these findings suggest that engagement with a narrative synchronizes listeners' responses in regions involved in mentalizing, reward, working memory and attention. By examining individual differences in engagement, we revealed that these synchronization patterns are due to engagement, and not due to differences in the narrative's content., Competing Interests: Declaration of Competing Interest The authors state that they have no competing financial interests or personal relationships that could have affected the work disclosed in this study., (Copyright © 2023 The Author(s). Published by Elsevier Inc. All rights reserved.)

Objects influence attention allocation; when a location within an object is cued, participants react faster to targets appearing in a different location within this object than on a different object. Despite consistent demonstrations of this object-based effect, there is no agreement regarding its underlying mechanisms. To test the most common hypothesis that attention spreads automatically along the cued object, we utilized a continuous, response-free measurement of attentional allocation that relies on the modulation of the pupillary light response. In Experiments 1 and 2, attentional spreading was not encouraged because the target appeared often (60%) at the cued location and considerably less often at other locations (20% within the same object and 20% on another object). In Experiment 3, spreading was encouraged because the target appeared equally often in one of the three possible locations within the cued object (cued end, middle, uncued end). In all experiments, we added gray-to-black and gray-to-white luminance gradients to the objects. By cueing the gray ends of the objects, we could track attention. If attention indeed spreads automatically along objects, then pupil size should be greater after the gray-to-dark object is cued because attention spreads toward darker areas of the object than when the gray-to-white object is cued, regardless of the target location probability. However, unequivocal evidence of attentional spreading was only found when spreading was encouraged. These findings do not support an automatic spreading of attention. Instead, they suggest that attentional spreading along the object is guided by cue-target contingencies. (PsycInfo Database Record (c) 2023 APA, all rights reserved).

Word embedding representations have been shown to be effective in predicting human neural responses to lingual stimuli. While these representations are sensitive to the textual context, they lack the extratextual sources of context such as prior knowledge, thoughts, and beliefs, all of which constitute the listener's perspective. In this study, we propose conceptualizing the listeners' perspective as a source that induces changes in the embedding space. We relied on functional magnetic resonance imaging data collected by Yeshurun Y, Swanson S, Simony E, Chen J, Lazaridi C, Honey CJ, Hasson U. Same story, different story: the neural representation of interpretive frameworks. Psychol Sci. 2017:28(3):307-319, in which two groups of human listeners (n = 40) were listening to the same story but with different perspectives. Using a dedicated fine-tuning process, we created two modified versions of a word embedding space, corresponding to the two groups of listeners. We found that each transformed space was better fitted with neural responses of the corresponding group, and that the spatial distances between these spaces reflect both interpretational differences between the perspectives and the group-level neural differences. Together, our results demonstrate how aligning a continuous embedding space to a specific context can provide a novel way of modeling listeners' intrinsic perspectives., (© The Author(s) 2023. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permission@oup.com.)

Recent political polarization has illustrated how individuals with opposing political views often experience ongoing events in markedly different ways. In this study, we explored the neural mechanisms underpinning this phenomenon. We conducted fMRI scanning of 34 right- and left-wing participants (45% females) watching political videos (e.g., campaign ads and political speeches) just before the elections in Israel. As expected, we observed significant differences between left- and right-wing participants in their interpretation of the videos' content. Furthermore, neuroimaging results revealed partisanship-dependent differences in activation and synchronization in higher-order regions. Surprisingly, such differences were also revealed in early sensory, motor, and somatosensory regions. We found that the political content synchronized the responses of primary visual and auditory cortices in a partisanship-dependent manner. Moreover, right-wing (and not left-wing) individuals' sensorimotor cortex was involved in processing right-wing (and not left-wing) political content. These differences were pronounced to the extent that we could predict political orientation from the early brain-response alone. Importantly, no such differences were found with respect to neutral content. Therefore, these results uncover more fundamental neural mechanisms underlying processes of political polarization. SIGNIFICANCE STATEMENT The political sphere has become highly polarized in recent years. Would it be possible to identify the neural mechanisms underpinning such processes? In our study, left- and right-wing participants were scanned in fMRI while watching political video clips just before the elections in Israel. We found that political content was potent in synchronizing the brain responses of individuals holding similar views. This was far more pronounced in individuals holding right-wing views. Moreover, partisan-dependent differences in neural responses were identified already in early sensory, somatosensory, and motor regions, and only for political content. These results suggest that individuals' political views shape their neural responses at a very basic level., (Copyright © 2023 the authors.)

Magnetoresistance measurements in amorphous NbN nanowires show that transport current affects their negative magnetoresistance (nMR) in a manner qualitatively similar to temperature. In particular, the current suppresses the nMR and, beyond a certain level it eliminates the effect altogether. As the temperature dependence of the nMR effect is more pronounced at low currents, similarly the current dependence of the effect is more pronounced at low temperatures. These results are discussed in terms of the phenomenological model which attributes the nMR to the interplay between the resistance originating from the rate of phase slips via the Josephson relation and the Ohmic contribution from quasiparticles charge imbalance that accompany fluctuations of the order parameter in the nanowire., (© 2022. The Author(s).)

We explored the potential of using real-time fMRI (rt-fMRI) neurofeedback training to bias interpretations of naturalistic narrative stimuli. Participants were randomly assigned to one of two possible conditions, each corresponding to a different interpretation of an ambiguous spoken story. While participants listened to the story in the scanner, neurofeedback was used to reward neural activity corresponding to the assigned interpretation. After scanning, final interpretations were assessed. While neurofeedback did not change story interpretations on average, participants with higher levels of decoding accuracy during the neurofeedback procedure were more likely to adopt the assigned interpretation; additional control conditions are needed to establish the role of individualized feedback in driving this result. While naturalistic stimuli introduce a unique set of challenges in providing effective and individualized neurofeedback, we believe that this technique holds promise for individualized cognitive therapy., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

In the COVID-19 era, physical interactions ubiquitously pose a disease threat. Using a novel online paradigm, this study tested whether under such unique circumstances, the fundamental motivation to avoid disease-related threats interacts with individual differences in sociability, such that: (i) responses to others are slowed down, particularly among sociable individuals, reflecting motivational tension; (ii) the role of sociability in predicting interaction likelihood is diminished. Participants (Israeli young adults, N  = 207) listened to auditory descriptions of everyday social situations, taking place in either the physical or virtual space, and decided quickly whether to interact. Participants also completed the Sociability Scale (Cheek & Buss, 1981). Responses were slower in the physical compared to virtual space, regardless of sociability. The association between interaction likelihood and sociability was stronger in the virtual space, with sociability mirrored by self-reported fear of COVID-19 in predicting interaction likelihood. We propose that when physical contact with others poses a threat to safety, fear supersedes sociability in guiding behavior in physical interactions., Competing Interests: None., (© 2021 Elsevier Ltd. All rights reserved.)

Synchronization has been identified as a key aspect in social bonding. While synchronization could be maximized by increasing the predictability of an interaction, such predictability is in tension with individuals' level of interest, which is tied to the interaction's complexity and novelty. In this study, we tested the interplay between synchronization and interest. We asked 104 female dyads to play the Mirror Game, in which they had to move their hands as coordinately as possible, and then report how much they liked each other. Utilizing information theory and video processing tools, we found that a combination of movement synchronization and complexity explained liking almost two times better than movement synchronization alone. Moreover, we found that people initiated novel and challenging interactions, even though they paid a price-being less synchronized. Examining the interactions' dynamics, we found that people who liked each other moved in a more synchronized, complex, and novel manner during most of the interaction. This suggests that in addition to synchronization, maintaining interest may be critical for positive social bonding. Thus, we propose a new framework in which balancing synchronization and interest, rather than merely maximizing synchronization, optimizes the interaction quality., (© 2022. The Author(s).)

Individuals differ considerably in the degree to which they benefit from attention allocation. Thus far, such individual differences were attributed to post-perceptual factors such as working-memory capacity. This study examined whether a perceptual factor - the level of internal noise - also contributes to this inter-individual variability in attentional effects. To that end, we estimated individual levels of internal noise from behavioral variability in an orientation discrimination task (with tilted gratings) using the double-pass procedure and the perceptual-template model. We also measured the effects of spatial attention in an acuity task: the participants reported the side of a square on which a small aperture appeared. Central arrows were used to engage sustained attention and peripheral cues to engage transient attention. We found reliable correlations between individual levels of internal noise and the effects of both types of attention, albeit of opposite directions: positive correlation with sustained attention and negative correlation with transient attention. These findings demonstrate that internal noise - a fundamental characteristic of visual perception - can predict individual differences in the effects of spatial attention, highlighting the intricate relations between perception and attention., (Copyright © 2021 Elsevier B.V. All rights reserved.)

Crowding refers to impaired object identification when presented with other objects, and it is well established that spatial crowding-crowding from adjacent objects-affects many aspects of visual perception and cognition. A similar interference also occurs across time-the identification of a target object is impaired when distracting objects precede and succeed it. When such interference is observed with relatively long interitem intervals it is termed temporal crowding. Thus far, little was known about temporal crowding and its underlying processes. Particularly it was unknown which aspects of visual processing are impaired by temporal crowding, and the answer to this question bears critical theoretical implications. To reveal the nature of this impairment we used a continuous-report task and a mixture-model analysis. In three experiments, observers viewed sequences of three oriented items separated by relatively long intervals (170-475ms). The target was the second item in the sequence, and the task was to reproduce its orientation. The findings suggest that temporal crowding impairs target encoding and increases substitution errors, but there was no evidence of a reduced signal-to-noise ratio. This pattern of results was similar regardless of stimuli duration and target-distractor similarity. However, it differed considerably from the pattern found for ordinary masking and spatial crowding, indicating that temporal crowding is a unique phenomenon. Moreover, the finding that temporal crowding affected the precision of target encoding even when the items were separated by almost half a second suggests that visual processing requires a surprisingly long time to complete., (© 2021. The Psychonomic Society, Inc.)

The necessity to wear facial masks in public during the COVID-19 pandemic generated a unique situation where the eyes' importance as a visual source of information about individuals' mental and emotional states greatly increased. In this study, we tested the hypothesis that experience in looking in interlocutor's eyes (as a result of mask-wearing) will be correlated with enhanced performance on "reading the mind in the eyes test" (RMET). To test this, 87 participants performed an online version of the RMET at 2 different timepoints: when the mandatory mask wearing rules were put in place and a month later. We found that reported tendency to look at interlocutors' eyes, combined with experience in interacting with other people wearing masks, explained individual differences in RMET performance. Moreover, we found that individual's tendency to look at interlocutors' eyes was correlated with change in performance in reading the mind in the eyes over this month. These results suggest that in addition to individual's interest and motivation in understanding other's mental state, continuous everyday experiences can result in an improved capacity for reading mental and emotional states by looking into individuals' eyes. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

The "Narratives" collection aggregates a variety of functional MRI datasets collected while human subjects listened to naturalistic spoken stories. The current release includes 345 subjects, 891 functional scans, and 27 diverse stories of varying duration totaling ~4.6 hours of unique stimuli (~43,000 words). This data collection is well-suited for naturalistic neuroimaging analysis, and is intended to serve as a benchmark for models of language and narrative comprehension. We provide standardized MRI data accompanied by rich metadata, preprocessed versions of the data ready for immediate use, and the spoken story stimuli with time-stamped phoneme- and word-level transcripts. All code and data are publicly available with full provenance in keeping with current best practices in transparent and reproducible neuroimaging., (© 2021. The Author(s).)

This study examined how the brain dynamically updates event representations by integrating new information over multiple minutes while segregating irrelevant input. A professional writer custom-designed a narrative with two independent storylines, interleaving across minute-long segments (ABAB). In the last (C) part, characters from the two storylines meet and their shared history is revealed. Part C is designed to induce the spontaneous recall of past events, upon the recurrence of narrative motifs from A/B, and to shed new light on them. Our fMRI results showed storyline-specific neural patterns, which were reinstated (i.e., became more active) during storyline transitions. This effect increased along the processing timescale hierarchy, peaking in the default mode network. Similarly, the neural reinstatement of motifs was found during Part C. Furthermore, participants showing stronger motif reinstatement performed better in integrating A/B and C events, demonstrating the role of memory reactivation in information integration over intervening irrelevant events., (© 2021 Massachusetts Institute of Technology.)

While a large body of evidence has demonstrated the effects of attention on spatial processes, we know much less about attentional effects on the complementary temporal aspects of visual perception. To narrow this knowledge gap, we examined the effects of endogenous attention-the voluntary component of spatial attention-on temporal integration using the Ternus display. In a typical Ternus display, horizontally aligned discs shift by one position across alternating frames that are separated by a varying interframe interval. This display can induce two different motion percepts: all three discs moving together back and forth (group motion), or the two central discs seeming to remain static and the outer disk jumping across them (element motion). Several studies suggest that element motion reflects temporal integration. Thus, we used the rate of element motion percept to measure temporal integration. Attention was manipulated via the degree of certainty regarding the discs' location (Experiment 1), or with central informative arrows (Experiment 2). The pattern of results was similar in both experiments: The participants reported perceiving element motion more often when attention was allocated in advance to the discs' location. These results suggest that attention prolongs the period of time over which information is integrated. (PsycInfo Database Record (c) 2021 APA, all rights reserved).

Reorganization of the maternal brain upon childbirth triggers the species-typical maternal social behavior. These brief social moments carry profound effects on the infant's brain and likely have a distinct signature in the maternal brain. Utilizing a double-blind, within-subject oxytocin/placebo administration crossover design, mothers' brain was imaged twice using fMRI while observing three naturalistic maternal-infant contexts in the home ecology; 'unavailable', 'unresponsive', and 'social', when mothers engaged in synchronous peek-a-boo play. The social condition elicited greater neural response across the human caregiving network, including amygdala, VTA, hippocampus, insula, ACC, and temporal cortex. Oxytocin impacted neural response primarily to the social condition and attenuated differences between social and non-social stimuli. Greater temporal consistency emerged in the 'social' condition across the two imaging sessions, particularly in insula, amygdala, and TP. Findings describe how mother's brain varies by caregiving experiences and gives salience to moments of social synchrony that support infant development and brain maturation., Competing Interests: OS, RS, MB, GA, YY, AU, OZ, RF No competing interests declared, (© 2021, Shimon-Raz et al.)

The default mode network (DMN) is classically considered an 'intrinsic' system, specializing in internally oriented cognitive processes such as daydreaming, reminiscing and future planning. In this Perspective, we suggest that the DMN is an active and dynamic 'sense-making' network that integrates incoming extrinsic information with prior intrinsic information to form rich, context-dependent models of situations as they unfold over time. We review studies that relied on naturalistic stimuli, such as stories and movies, to demonstrate how an individual's DMN neural responses are influenced both by external information accumulated as events unfold over time and by the individual's idiosyncratic past memories and knowledge. The integration of extrinsic and intrinsic information over long timescales provides a space for negotiating a shared neural code, which is necessary for establishing shared meaning, shared communication tools, shared narratives and, above all, shared communities and social networks.

It is widely accepted that voluntary spatial attention is slow - it can only affect performance with medium and long cue-target intervals. Here, we examined whether this also holds for voluntary temporal attention. We performed a rigorous examination of the time-course of attention allocation to a point in time using two common paradigms for studying endogenous temporal attention: 'constant foreperiod' and 'temporal orienting'. With both paradigms, the task required non-speeded identification of a letter, whose presentation was preceded by a warning cue. This cue was either auditory or visual, and it was either informative or uninformative. Critically, to avoid exogenous attention, the cues did not involve an intensity change. We found significantly higher identification accuracy when the cue was informative than uninformative, suggesting that temporal attention improved perceptual processing. Importantly, reliable effects of temporal attention on perceptual processing were found with as little as 150 ms from cue onset and up to 2400 ms. Hence, measuring endogenous attention in the temporal domain revealed a twofold faster mechanism than what was believed based on measurements in the spatial domain. These findings challenge the common assumption that voluntary processes are inherently slow. Instead, they portray voluntary mechanisms as considerably more flexible and dynamic, and they further underscore the importance of incorporating the temporal domain into the study of human perception., (Copyright © 2020 Elsevier B.V. All rights reserved.)

Simultanagnosia is an impairment in processing multiple visual elements simultaneously consecutive to bilateral posterior parietal damage, and neuroimaging data have specifically implicated the superior parietal lobule (SPL) in multiple element processing. We previously reported that a patient with focal and bilateral lesions of the SPL performed slower than controls in visual search but only for stimuli consisting of separable lines. Here, we further explored this patient's visual processing of plain object (colored disk) versus object consisting of separable lines (letter), presented in isolation (single object) versus in triplets. Identification of objects was normal in isolation but dropped to chance level when surrounded by distracters, irrespective of eccentricity and spacing. We speculate that this poor performance reflects a deficit in processing objects' relative locations within the triplet (for colored disks), aggravated by a deficit in processing the relative location of each separable line (for letters). Confirming this, performance improved when the patient just had to detect the presence of a specific colored disk within the triplets (visual search instruction), while the inability to identify the middle letter was alleviated when the distracters were identical letters that could be grouped, thereby reducing the number of ways individual lines could be bound., (© The Author(s) 2020. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

Studies of nanoscale superconducting structures have revealed various physical phenomena and led to the development of a wide range of applications. Most of these studies concentrated on one- and two-dimensional structures due to the lack of approaches for creation of fully engineered three-dimensional (3D) nanostructures. Here, we present a 'bottom-up' method to create 3D superconducting nanostructures with prescribed multiscale organization using DNA-based self-assembly methods. We assemble 3D DNA superlattices from octahedral DNA frames with incorporated nanoparticles, through connecting frames at their vertices, which result in cubic superlattices with a 48 nm unit cell. The superconductive superlattice is formed by converting a DNA superlattice first into highly-structured 3D silica scaffold, to turn it from a soft and liquid-environment dependent macromolecular construction into a solid structure, following by its coating with superconducting niobium (Nb). Through low-temperature electrical characterization we demonstrate that this process creates 3D arrays of Josephson junctions. This approach may be utilized in development of a variety of applications such as 3D Superconducting Quantum interference Devices (SQUIDs) for measurement of the magnetic field vector, highly sensitive Superconducting Quantum Interference Filters (SQIFs), and parametric amplifiers for quantum information systems.

Temporal attention can be entrained exogenously to rhythms. Indeed, faster and more accurate responses were previously found when the target appeared in-phase with a preceding rhythm in comparison to when it was out of phase. However, the nature of this rhythm-induced attentional effect is not well understood. To better understand the processes underlying rhythm-induced attention, we employed a continuous measure of perceived orientation and a mixture-model analysis. A trial in our study started with a sequence of auditory beeps separated by a fixed inter-beeps interval in the regular (rhythmic) condition or by variable inter-beeps intervals in the irregular condition. A visual target-a line embedded in a circle-followed the sequence. The 'critical' interval between the last beep and the target was chosen randomly from several possible Inter-Onset Intervals (IOIs), of which only one was in-phase with the rhythm. The target was followed by a probe line, and the participants were asked to rotate it to reproduce the target's orientation. The measure of performance for a given trial was the difference in degrees between the orientation of the target and that reproduced by the observer. We found that guessing rate was lower with regular than irregular rhythms. However, there was no effect of rhythm type (regular vs irregular) on the quality of representation (measured as the variability in reproducing the target). Furthermore, the rhythm effect was present only when rhythm type was fixed within a block, and it was found with all IOIs, not just the in-phase IOI. This lack of specificity suggests that these results reflect a general effect of rhythm on alertness., Competing Interests: The authors have declared that no competing interests exist.

Understanding how spatial attention is distributed over space (i.e. the attentional window) is highly important for theoretical, methodological, as well as applied reasons. One fundamental challenge to the study of the attentional window is that most of our current knowledge is based on measuring distractors interference, or relying in some other way on properties of the participants' responses (e.g. response time). However, other factors such as distractor visibility may mediate distractor interference, and in general participants' response can be influenced by many other factors including higher-level strategies, experience, response history, response biases, and so on. Recent paradigms, which do not rely on participants' response, such as measuring attentional modulations of the pupillary light response, may help us face this challenge., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

This study examined the role of advance expectations in generating relevance-based selection, using a version of cognitive "blindness" that is driven solely by task relevance. With this irrelevance-induced blindness, participants often fail to report a feature of an irrelevant stimulus, even though the levels of perceptual and cognitive load are minimal (i.e., capacity limitations are not met). Hence, with this phenomenon, selection is based solely on task relevance. In two experiments, we examined such relevance-based selection with a new paradigm in which the participants had to report the location of an object appearing on one of two rings. Critically, while in Experiment 1 the participants could form advance expectations regarding the (ir) relevant stimuli, because the location of the relevant ring and the shape and color of the relevant object were known in advance, in Experiment 2 no concrete advance expectations could be formed. This was established by varying randomly, from trial to trial, the shape, color, and location of relevant and irrelevant stimuli. We found strong irrelevance-induced blindness in both experiments, regardless of whether or not advance expectations were formed. These findings suggest that advance expectations, at least with regard to the task-relevant stimulus' location shape or color, are not necessary for irrelevance-induced blindness to occur; more generally, this implies that such expectations do not play a critical role in selection processes that are based solely on task relevance. We further discuss these findings in the context of Garnerian and Posnerian selection, and their relationship to visual awareness.

Attention can be subdivided into several components, including alertness and spatial attention. It is believed that the behavioral benefits of attention, such as increased accuracy and faster reaction times, are generated by an increase in neural activity and a decrease in neural variability, which enhance the signal-to-noise ratio of task-relevant neural populations. However, empirical evidence regarding attention-related changes in neural variability in humans is extremely rare. Here we used EEG to demonstrate that trial-by-trial neural variability was reduced by visual cues that modulated alertness and spatial attention. Reductions in neural variability were specific to the visual system and larger in the contralateral hemisphere of the attended visual field. Subjects with higher initial levels of neural variability and larger decreases in variability exhibited greater behavioral benefits from attentional cues. These findings demonstrate that both alertness and spatial attention modulate neural variability and highlight the importance of reducing/quenching neural variability for attaining the behavioral benefits of attention. SIGNIFICANCE STATEMENT Attention is thought to improve perception by increasing the signal-to-noise ratio of the neuronal populations that encode the attended stimulus. Signal-to-noise ratio can be enhanced by increasing neural response (signal) and/or by reducing neural variability (noise). The ability of attention to increase neural responses has been studied extensively, but the effects of attention on neural variability have rarely been examined in humans. Here, we demonstrate that modulating different components of attention, including alertness and spatial attention, reduces neural variability in humans. Furthermore, we show that subjects with larger reductions in neural variability exhibit greater behavioral benefits from attention. These results demonstrate that reduction of neural variability is a fundamental feature of attentional processes in humans with clear behavioral importance., (Copyright © 2019 the authors.)

Development of high-power superconducting applications requires the accurate estimation of AC losses in the superconductor. In applications such as superconducting magnetic energy storage, the charge/discharge/persistent switching frequency of the coil, resulting from pulse width modulation control algorithms, is usually in the kilohertz regime. Therefore, a thorough investigation of the losses in the kilohertz regime of AC currents superimposed on large DC currents is essential in order to ensure the device stable operation at a predefined temperature. We describe here a unique experimental setup designed and built for characterizing AC losses in superconducting wires and coils under such special conditions. To minimize the eddy currents induced in the apparatus, a cryostat vacuum vessel was made of Delrin, an insulating synthetic polymer. The measurement setup allows driving DC currents up to 150 A and superimposed AC currents with amplitudes up to 10 A rms and frequencies up to 18 kHz. The system utilizes conduction cooling to reach a wide range of temperatures between 6 and 100 K and allows measurements of 10 cm long superconducting wires and coils with a diameter of 40 cm. The loss is measured by the electrical method, i.e., by direct voltage and current waveform measurement, achieving a resolution better than 100 nW. The system described here will assist in developing superconducting wires and coils for high-power applications.

Magnetoresistance measurements in a granular Nb nanoring reveal current-induced crossover between two distinct quantum coherence effects. At low bias currents, Cooper-pair coherence is manifested by Little-Parks oscillations with flux periodicity of h/2 e. At high bias currents, magnetoresistance oscillations with flux periods of h/ e are observed and interpreted as Aharonov-Bohm oscillations, reflecting the phase coherence of individual quasi-particles. The model explaining these data views the ring as a chain of superconducting grains weakly coupled by tunnel junctions. Low bias currents allow coherent tunneling of Cooper pairs between the grains. Increasing the current above the critical current of all the junctions creates a quasi-particles conduction channel along the ring, allowing for quantum interference of quasi-particles.

This study measured the size of the attentional window when attention is narrowly focused, using attentional modulation of the pupillary light response - pupillary constriction when covertly attending a brighter than darker area. This allowed us to avoid confounds and biases involved in relying on observers' response (e.g., RT), which contaminated previous measurements of this window. We presented letters to the right and left of fixation, each surrounded by task-irrelevant disks with varying distances. The disks were bright on one side and dark on the other. A central cue indicated which letter to attend. Luminance levels were identical across trials. We found that pupil size was modulated by the disks' luminance when they were 1° away from the attended letter, but not when this distance was larger. This suggests that the diameter of the attentional window is at least 2°, which is twice as large as that established with behavioral measurements.

When two verniers are presented in rapid succession at the same location, feature fusion occurs. Instead of perceiving two separate verniers, participants typically report perceiving one fused vernier, whose offset is a combination of the two previous verniers, with the later one slightly dominating. Here, we examined the effects of sustained attention-the voluntary component of spatial attention-on feature fusion. One way to manipulate sustained attention is via the degree of certainty regarding the stimulus location. In the attended condition, the stimulus appeared always in the same location, and in the unattended condition it could appear in one of two possible locations. Participants had to report the offset of the fused vernier. Experiments 1 and 2 measured attentional effects on feature fusion with and without eye-tracking. In both experiments, we found a higher rate of reports corresponding to the offset of the second vernier with focused attention than without focused attention, suggesting that attention strengthened the final percept emerging from the fusion operation. In Experiment 3, we manipulated the stimulus duration to encourage a final fused percept that is dominated by either the first or second vernier. We found that attention strengthened the already dominant percept, regardless of whether it corresponded to the offset of the first or second vernier. These results are consistent with an attentional mechanism of signal enhancement at the encoding stage.

In this work, we describe a low-cost, two-step synthesis of composites of nitrogen-doped carbon quantum dots (NCDs) with γ-Fe 2 O 3 (NCDs/γ-Fe 2 O 3 ), which is based on a hydrothermal cum co-precipitation method. The product is a fine powder of particles having an average diameter of 9 ± 3 nm. The physical and chemical properties of NCDs/γ-Fe 2 O 3 were studied, as well as the superconducting quantum interference device and Mossbauer analysis of the magnetic properties of these nanocomposites. The interaction of NCDs/γ-Fe 2 O 3 nanocomposites with neuron-like cells was examined, showing efficient uptake and low toxicity. Our research demonstrates the use of the nanocomposites for imaging and for controlling the cellular motility. The NCDs/γ-Fe 2 O 3 nanocomposites are promising because of their biocompatibility, photostability, and potential selective affinity, paving the way for multifunctional biomedical applications., Competing Interests: The authors declare no competing financial interest.

The present study examined the mutual influence of cortical neuroenhancement and allocation of spatial attention on perception. Specifically, it explored the effects of transcranial Direct Current Stimulation (tDCS) on visual acuity measured with a Landolt gap task and attentional precues. The exogenous cues were used to draw attention either to the location of the target or away from it, generating significant performance benefits and costs. Anodal tDCS applied to posterior occipital area for 15 min improved performance during stimulation, reflecting heightened visual acuity. Reaction times were lower, and accuracy was higher in the tDCS group, compared to a sham control group. Additionally, in post-stimulation trials tDCS significantly interacted with the effect of precuing. Reaction times were lower in valid cued trials (benefit) and higher in invalid trials (cost) compared to neutrally cued trials, the effect which was pronounced stronger in tDCS group than in sham control group. The increase of cost and benefit effects in the tDCS group was of a similar magnitude, suggesting that anodal tDCS influenced the overall process of attention orienting. The observed interaction between the stimulation of the visual cortex and precueing indicates a magnification of attention modulation.

Previous studies on the role of attention in perceptual grouping have yielded contradicting findings, some suggesting that grouping requires attention and others indicating that it does not. Kimchi and Razpurker-Apfeld (Psychonomic Bulletin and Review, 11(4), 687-696, 2004) showed that attentional demands in grouping could vary according to the processes involved. The current study expanded on this, examining whether attentional demands vary for (a) different grouping principles and (b) as a function of contingent processing of element segregation and shape formation. We used the inattention paradigm with an online measure, in which participants engaged in an attentionally demanding change-detection task on a small matrix presented on a task-irrelevant backdrop of grouped elements. The backdrop grouping changed or stayed the same independently of any change in the target. Congruency effects produced by changes in backdrop grouping on target-change judgments indicate that the backdrop grouping was accomplished under inattention. The results showed congruency effects when grouping formed columns/rows by proximity but not by shape similarity, and when grouping into a distinct shape by collinearity did not involve element segregation. No congruency effects were found when grouping into a shape by collinearity or connectedness involved element segregation, except when connectedness was combined with color similarity. These results suggest that attentional demands depend on the combination of grouping principles and the complexity of the processes involved in the organization. These findings provide further support for the view that perceptual organization is a multiplicity of processes that vary in attentional demands.

Small changes in word choice can lead to dramatically different interpretations of narratives. How does the brain accumulate and integrate such local changes to construct unique neural representations for different stories? In this study, we created two distinct narratives by changing only a few words in each sentence (e.g., "he" to "she" or "sobbing" to "laughing") while preserving the grammatical structure across stories. We then measured changes in neural responses between the two stories. We found that differences in neural responses between the two stories gradually increased along the hierarchy of processing timescales. For areas with short integration windows, such as early auditory cortex, the differences in neural responses between the two stories were relatively small. In contrast, in areas with the longest integration windows at the top of the hierarchy, such as the precuneus, temporal parietal junction, and medial frontal cortices, there were large differences in neural responses between stories. Furthermore, this gradual increase in neural differences between the stories was highly correlated with an area's ability to integrate information over time. Amplification of neural differences did not occur when changes in words did not alter the interpretation of the story (e.g., sobbing to "crying"). Our results demonstrate how subtle differences in words are gradually accumulated and amplified along the cortical hierarchy as the brain constructs a narrative over time., Competing Interests: The authors declare no conflict of interest.

The quest for the by-design assembly of material and devices from nanoscale inorganic components is well recognized. Conventional self-assembly is often limited in its ability to control material morphology and structure simultaneously. Here, we report a general method of assembling nanoparticles in a linear "pillar" morphology with regulated internal configurations. Our approach is inspired by supramolecular systems, where intermolecular stacking guides the assembly process to form diverse linear morphologies. Programmable stacking interactions were realized through incorporation of DNA coded recognition between the designed planar nanoparticle clusters. This resulted in the formation of multilayered pillar architectures with a well-defined internal nanoparticle organization. By controlling the number, position, size, and composition of the nanoparticles in each layer, a broad range of nanoparticle pillars were assembled and characterized in detail. In addition, we demonstrated the utility of this stacking assembly strategy for investigating plasmonic and electrical transport properties.

The study of graphene-based antivirals is still at a nascent stage and the photothermal antiviral properties of graphene have yet to be studied. Here, we design and synthesize sulfonated magnetic nanoparticles functionalized with reduced graphene oxide (SMRGO) to capture and photothermally destroy herpes simplex virus type 1 (HSV-1). Graphene sheets were uniformly anchored with spherical magnetic nanoparticles (MNPs) of varying size between ∼5 and 25 nm. Fourier-transform infrared spectroscopy (FT-IR) confirmed the sulfonation and anchoring of MNPs on the graphene sheets. Upon irradiation of the composite with near-infrared light (NIR, 808 nm, 7 min), SMRGO (100 ppm) demonstrated superior (∼99.99%) photothermal antiviral activity. This was probably due to the capture efficiency, unique sheet-like structure, high surface area, and excellent photothermal properties of graphene. In addition, electrostatic interactions of MNPs with viral particles appear to play a vital role in the inhibition of viral infection. These results suggest that graphene composites may help to combat viral infections including, but not only, HSV-1.

This study examined whether the recurrent difficulty to replicate results obtained with paradigms measuring distractor processing as a function of perceptual load is due to individual differences. We first reanalyzed, at the individual level, the data of eight previously reported experiments. These reanalyses revealed substantial inter-individual differences, with particularly low percentage of participants whose performance matched the load theory's predictions (i.e., larger distractor interference with low than high levels of load). Moreover, frequently the results were opposite to the theory's predictions-larger interference in the high than low load condition; and often a reversed compatibility effect emerged-better performance in the incompatible than neutral condition. Subsequently, seven observers participated in five identical experimental sessions. If the observed inter-individual differences are due to some stable trait or perceptual capacity, similar results should have emerged in all sessions of a given participant. However, all seven participants showed large between-sessions variations with similar patterns to those found between participants. These findings question the theoretical foundation implemented with these paradigms, as none of the theories suggested thus far can account for such inter- and intra-individual differences. Thus, these paradigms should be used with caution until further research will provide better understanding of what they actually measure.