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1.
Nature ; 620(7974): 533-537, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37587298

RESUMO

Controlling quantum materials with light is of fundamental and technological importance. By utilizing the strong coupling of light and matter in optical cavities1-3, recent studies were able to modify some of their most defining features4-6. Here we study the magneto-optical properties of a van der Waals magnet that supports strong coupling of photons and excitons even in the absence of external cavity mirrors. In this material-the layered magnetic semiconductor CrSBr-emergent light-matter hybrids called polaritons are shown to substantially increase the spectral bandwidth of correlations between the magnetic, electronic and optical properties, enabling largely tunable optical responses to applied magnetic fields and magnons. Our results highlight the importance of exciton-photon self-hybridization in van der Waals magnets and motivate novel directions for the manipulation of quantum material properties by strong light-matter coupling.

2.
Proc Natl Acad Sci U S A ; 121(9): e2310012121, 2024 Feb 27.
Artigo em Inglês | MEDLINE | ID: mdl-38377194

RESUMO

Sex plays a crucial role in human brain development, aging, and the manifestation of psychiatric and neurological disorders. However, our understanding of sex differences in human functional brain organization and their behavioral consequences has been hindered by inconsistent findings and a lack of replication. Here, we address these challenges using a spatiotemporal deep neural network (stDNN) model to uncover latent functional brain dynamics that distinguish male and female brains. Our stDNN model accurately differentiated male and female brains, demonstrating consistently high cross-validation accuracy (>90%), replicability, and generalizability across multisession data from the same individuals and three independent cohorts (N ~ 1,500 young adults aged 20 to 35). Explainable AI (XAI) analysis revealed that brain features associated with the default mode network, striatum, and limbic network consistently exhibited significant sex differences (effect sizes > 1.5) across sessions and independent cohorts. Furthermore, XAI-derived brain features accurately predicted sex-specific cognitive profiles, a finding that was also independently replicated. Our results demonstrate that sex differences in functional brain dynamics are not only highly replicable and generalizable but also behaviorally relevant, challenging the notion of a continuum in male-female brain organization. Our findings underscore the crucial role of sex as a biological determinant in human brain organization, have significant implications for developing personalized sex-specific biomarkers in psychiatric and neurological disorders, and provide innovative AI-based computational tools for future research.


Assuntos
Aprendizado Profundo , Doenças do Sistema Nervoso , Adulto Jovem , Humanos , Masculino , Feminino , Caracteres Sexuais , Encéfalo , Envelhecimento
3.
Proc Natl Acad Sci U S A ; 121(22): e2316149121, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38768342

RESUMO

Speech impediments are a prominent yet understudied symptom of Parkinson's disease (PD). While the subthalamic nucleus (STN) is an established clinical target for treating motor symptoms, these interventions can lead to further worsening of speech. The interplay between dopaminergic medication, STN circuitry, and their downstream effects on speech in PD is not yet fully understood. Here, we investigate the effect of dopaminergic medication on STN circuitry and probe its association with speech and cognitive functions in PD patients. We found that changes in intrinsic functional connectivity of the STN were associated with alterations in speech functions in PD. Interestingly, this relationship was characterized by altered functional connectivity of the dorsolateral and ventromedial subdivisions of the STN with the language network. Crucially, medication-induced changes in functional connectivity between the STN's dorsolateral subdivision and key regions in the language network, including the left inferior frontal cortex and the left superior temporal gyrus, correlated with alterations on a standardized neuropsychological test requiring oral responses. This relation was not observed in the written version of the same test. Furthermore, changes in functional connectivity between STN and language regions predicted the medication's downstream effects on speech-related cognitive performance. These findings reveal a previously unidentified brain mechanism through which dopaminergic medication influences speech function in PD. Our study sheds light into the subcortical-cortical circuit mechanisms underlying impaired speech control in PD. The insights gained here could inform treatment strategies aimed at mitigating speech deficits in PD and enhancing the quality of life for affected individuals.


Assuntos
Idioma , Doença de Parkinson , Fala , Núcleo Subtalâmico , Humanos , Doença de Parkinson/fisiopatologia , Doença de Parkinson/tratamento farmacológico , Núcleo Subtalâmico/fisiopatologia , Núcleo Subtalâmico/efeitos dos fármacos , Masculino , Fala/fisiologia , Fala/efeitos dos fármacos , Feminino , Pessoa de Meia-Idade , Idoso , Imageamento por Ressonância Magnética , Dopamina/metabolismo , Rede Nervosa/efeitos dos fármacos , Rede Nervosa/fisiopatologia , Cognição/efeitos dos fármacos , Dopaminérgicos/farmacologia , Dopaminérgicos/uso terapêutico
4.
Proc Natl Acad Sci U S A ; 121(15): e2315167121, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38557177

RESUMO

The default mode network (DMN) is a large-scale brain network known to be suppressed during a wide range of cognitive tasks. However, our comprehension of its role in naturalistic and unconstrained behaviors has remained elusive because most research on the DMN has been conducted within the restrictive confines of MRI scanners. Here, we use multisite GCaMP (a genetically encoded calcium indicator) fiber photometry with simultaneous videography to probe DMN function in awake, freely exploring rats. We examined neural dynamics in three core DMN nodes-the retrosplenial cortex, cingulate cortex, and prelimbic cortex-as well as the anterior insula node of the salience network, and their association with the rats' spatial exploration behaviors. We found that DMN nodes displayed a hierarchical functional organization during spatial exploration, characterized by stronger coupling with each other than with the anterior insula. Crucially, these DMN nodes encoded the kinematics of spatial exploration, including linear and angular velocity. Additionally, we identified latent brain states that encoded distinct patterns of time-varying exploration behaviors and found that higher linear velocity was associated with enhanced DMN activity, heightened synchronization among DMN nodes, and increased anticorrelation between the DMN and anterior insula. Our findings highlight the involvement of the DMN in collectively and dynamically encoding spatial exploration in a real-world setting. Our findings challenge the notion that the DMN is primarily a "task-negative" network disengaged from the external world. By illuminating the DMN's role in naturalistic behaviors, our study underscores the importance of investigating brain network function in ecologically valid contexts.


Assuntos
Rede de Modo Padrão , Roedores , Ratos , Animais , Córtex Cerebral , Encéfalo/diagnóstico por imagem , Giro do Cíngulo/diagnóstico por imagem , Mapeamento Encefálico , Imageamento por Ressonância Magnética , Rede Nervosa/diagnóstico por imagem
5.
Nature ; 585(7825): 379-382, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32939065

RESUMO

The field of plasmonics, which studies the resonant interactions of electromagnetic waves and free electrons in solid-state materials1, has yet to be put to large-scale commercial application2 owing to the large amount of loss that usually occurs in plasmonic materials3. Organic light-emitting devices (OLEDs)4-7 have been incorporated into billions of commercial products because of their good colour saturation, versatile form factor8 and low power consumption9, but could still be improved in terms of efficiency and stability. Although OLEDs incorporating organic phosphors achieve an internal charge-to-light conversion of unity10, their refractive index contrast reduces the observable fraction of photons outside the device to around 25 per cent11-13. Further, during OLED operation, a localized buildup of slow-decaying14 triplet excitons and charges15 gradually reduces the brightness of the device in a process called ageing16,17, which can result in 'burn-in' effects on the display. Simultaneously improving device efficiency and stability is of paramount importance for OLED technology. Here we demonstrate an OLED that uses the decay rate enhancement18 of a plasmonic system to increase device stability, while maintaining efficiency by incorporating a nanoparticle-based out-coupling scheme to extract energy from the plasmon mode. Using an archetypal phosphorescent emitter, we achieve a two-fold increase in operational stability at the same brightness as a reference conventional device while simultaneously extracting 16 per cent of the energy from the plasmon mode as light. Our approach to increasing OLED stability avoids material-specific designs19-22 and is applicable to all commercial OLEDs that are currently used for lighting panels, televisions and mobile displays.

6.
Lancet ; 403(10443): 2489-2503, 2024 Jun 08.
Artigo em Inglês | MEDLINE | ID: mdl-38782004

RESUMO

BACKGROUND: Polycystic ovary syndrome (PCOS) is the most common cause of anovulatory infertility. Obesity exacerbates the reproductive complications of PCOS; however, the management of obesity in women with PCOS remains a large unmet clinical need. Observational studies have indicated that bariatric surgery could improve the rates of ovulatory cycles and prospects of fertility; however, the efficacy of surgery on ovulation rates has not yet been compared with behavioural modifications and medical therapy in a randomised trial. The aim of this study was to compare the safety and efficacy of bariatric surgery versus medical care on ovulation rates in women with PCOS, obesity, and oligomenorrhoea or amenorrhoea. METHODS: In this multicentre, open-label, randomised controlled trial, 80 women older than 18 years, with a diagnosis of PCOS based on the 2018 international evidence-based guidelines for assessing and managing PCOS, and a BMI of 35 kg/m2 or higher, were recruited from two specialist obesity management centres and via social media. Participants were randomly assigned at a 1:1 ratio to either vertical sleeve gastrectomy or behavioural interventions and medical therapy using a computer-generated random sequence (PLAN procedure in SAS) by an independent researcher not involved with any other aspect of the clinical trial. The median age of the entire cohort was 31 years and 79% of participants were White. The primary outcome was the number of biochemically confirmed ovulatory events over 52 weeks, and was assessed using weekly serum progesterone measurements. The primary endpoint included the intention-to-treat population and safety analyses were per-protocol population. This study is registered with the ISRCTN registry (ISRCTN16668711). FINDINGS: Participants were recruited from Feb 20, 2020 to Feb 1, 2021. 40 participants were assigned to each group and there were seven dropouts in the medical group and ten dropouts in the surgical group. The median number of ovulations was 6 (IQR 3·5-10·0) in the surgical group and 2 (0·0-4·0) in the medical group. Women in the surgical group had 2.5 times more spontaneous ovulations compared with the medical group (incidence rate ratio 2·5 [95% CI 1·5-4·2], p<0·0007). There were more complications in the surgical group than the medical group, although without long-term sequelae. There were 24 (66·7%) adverse events in the surgical group and 12 (30·0%) in the medical group. There were no treatment-related deaths. INTERPRETATION: Bariatric surgery was more effective than medical care for the induction of spontaneous ovulation in women with PCOS, obesity, and oligomenorrhoea or amenorrhoea. Bariatric surgery could, therefore, enhance the prospects of spontaneous fertility in this group of women. FUNDING: The Jon Moulton Charity Trust.


Assuntos
Cirurgia Bariátrica , Obesidade , Ovulação , Síndrome do Ovário Policístico , Humanos , Síndrome do Ovário Policístico/complicações , Síndrome do Ovário Policístico/cirurgia , Feminino , Adulto , Cirurgia Bariátrica/efeitos adversos , Cirurgia Bariátrica/métodos , Obesidade/complicações , Obesidade/cirurgia , Oligomenorreia , Resultado do Tratamento , Amenorreia/etiologia , Adulto Jovem , Gastrectomia/métodos , Gastrectomia/efeitos adversos , Infertilidade Feminina/etiologia
7.
Mol Psychiatry ; 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38605171

RESUMO

A major genetic risk factor for psychosis is 22q11.2 deletion (22q11.2DS). However, robust and replicable functional brain signatures of 22q11.2DS and 22q11.2DS-associated psychosis remain elusive due to small sample sizes and a focus on small single-site cohorts. Here, we identify functional brain signatures of 22q11.2DS and 22q11.2DS-associated psychosis, and their links with idiopathic early psychosis, using one of the largest multi-cohort data to date. We obtained multi-cohort clinical phenotypic and task-free fMRI data from 856 participants (101 22q11.2DS, 120 idiopathic early psychosis, 101 idiopathic autism, 123 idiopathic ADHD, and 411 healthy controls) in a case-control design. A novel spatiotemporal deep neural network (stDNN)-based analysis was applied to the multi-cohort data to identify functional brain signatures of 22q11.2DS and 22q11.2DS-associated psychosis. Next, stDNN was used to test the hypothesis that the functional brain signatures of 22q11.2DS-associated psychosis overlap with idiopathic early psychosis but not with autism and ADHD. stDNN-derived brain signatures distinguished 22q11.2DS from controls, and 22q11.2DS-associated psychosis with very high accuracies (86-94%) in the primary cohort and two fully independent cohorts without additional training. Robust distinguishing features of 22q11.2DS-associated psychosis emerged in the anterior insula node of the salience network and the striatum node of the dopaminergic reward pathway. These features also distinguished individuals with idiopathic early psychosis from controls, but not idiopathic autism or ADHD. Our results reveal that individuals with 22q11.2DS exhibit a highly distinct functional brain organization compared to controls. Additionally, the brain signatures of 22q11.2DS-associated psychosis overlap with those of idiopathic early psychosis in the salience network and dopaminergic reward pathway, providing substantial empirical support for the theoretical aberrant salience-based model of psychosis. Collectively, our findings, replicated across multiple independent cohorts, advance the understanding of 22q11.2DS and associated psychosis, underscoring the value of 22q11.2DS as a genetic model for probing the neurobiological underpinnings of psychosis and its progression.

9.
Proc Natl Acad Sci U S A ; 119(34): e2202515119, 2022 08 23.
Artigo em Inglês | MEDLINE | ID: mdl-35981139

RESUMO

Marital attachment plays an important role in maintaining intimate personal relationships and sustaining psychological well-being. Mate-selection theories suggest that people are more likely to marry someone with a similar personality and social status, yet evidence for the association between personality-based couple similarity measures and marital satisfaction has been inconsistent. A more direct and useful approach for understanding fundamental processes underlying marital satisfaction is to probe similarity of dynamic brain responses to maritally and socially relevant communicative cues, which may better reflect how married couples process information in real time and make sense of their mates and themselves. Here, we investigate shared neural representations based on intersubject synchronization (ISS) of brain responses during free viewing of marital life-related, and nonmarital, object-related movies. Compared to randomly selected pairs of couples, married couples showed significantly higher levels of ISS during viewing of marital movies and ISS between married couples predicted higher levels of marital satisfaction. ISS in the default mode network emerged as a strong predictor of marital satisfaction and canonical correlation analysis revealed a specific relation between ISS in this network and shared communication and egalitarian components of martial satisfaction. Our findings demonstrate that brain similarities that reflect real-time mental responses to subjective perceptions, thoughts, and feelings about interpersonal and social interactions are strong predictors of marital satisfaction, reflecting shared values and beliefs. Our study advances foundational knowledge of the neurobiological basis of human pair bonding.


Assuntos
Encéfalo , Casamento , Satisfação Pessoal , Encéfalo/fisiologia , Comunicação , Humanos , Relações Interpessoais , Casamento/psicologia , Personalidade , Cônjuges/psicologia
10.
Nano Lett ; 24(2): 557-565, 2024 Jan 17.
Artigo em Inglês | MEDLINE | ID: mdl-38179964

RESUMO

The manipulation of molecular excited state processes through strong coupling has attracted significant interest for its potential to provide precise control of photochemical phenomena. However, the key limiting factor for achieving this control has been the "dark-state problem", in which photoexcitation populates long-lived reservoir states with energies and dynamics similar to those of bare excitons. Here, we use a sensitive ultrafast transient reflection method with momentum and spectral resolution to achieve the selective excitation of organic exciton-polaritons in open photonic cavities. We show that the energy dispersions of these systems allow us to avoid the parasitic effect of the reservoir states. Under phase-matching conditions, we observe the direct population and decay of polaritons on time scales of less than 100 fs and find that momentum scattering processes occur on even faster time scales. We establish that it is possible to overcome the "dark state problem" through the careful design of strongly coupled systems.

11.
Nano Lett ; 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38598721

RESUMO

Realizing lattices of exciton polariton condensates has been of much interest owing to the potential of such systems to realize analogue Hamiltonian simulators and physical computing architectures. Here, we report the realization of a room temperature polariton condensate lattice using a direct-write approach. Polariton condensation is achieved in a microcavity embedded with host-guest Frenkel excitons of an organic dye (rhodamine) in a small-molecule ionic isolation lattice (SMILES). The microcavity is patterned using focused ion beam etching to realize arbitrary lattice geometries, including defect sites on demand. The band structure of the lattice and the emergence of condensation are imaged using momentum-resolved spectroscopy. The introduction of defect sites is shown to lower the condensation threshold and result in the formation of a defect band in the condensation spectrum. The present approach allows us to study periodic, quasiperiodic, and disordered polariton condensate lattices at room temperature using a direct-write approach.

12.
J Neurosci ; 43(17): 3159-3175, 2023 04 26.
Artigo em Inglês | MEDLINE | ID: mdl-36963847

RESUMO

Electrical stimulation of the medial temporal lobe (MTL) has the potential to uncover causal circuit mechanisms underlying memory function. However, little is known about how MTL stimulation alters information flow with frontoparietal cortical regions implicated in episodic memory. We used intracranial EEG recordings from humans (14 participants, 10 females) to investigate how MTL stimulation alters directed information flow between MTL and PFC and between MTL and posterior parietal cortex (PPC). Participants performed a verbal episodic memory task during which they were presented with words and asked to recall them after a delay of ∼20 s; 50 Hz stimulation was applied to MTL electrodes on selected trials during memory encoding. Directed information flow was examined using phase transfer entropy. Behaviorally, we observed that MTL stimulation reduced memory recall. MTL stimulation decreased top-down PFC→MTL directed information flow during both memory encoding and subsequent memory recall, revealing aftereffects more than 20 s after end of stimulation. Stimulation suppressed top-down PFC→MTL influences to a greater extent than PPC→MTL. Finally, MTL→PFC information flow on stimulation trials was significantly lower for successful, compared with unsuccessful, memory recall; in contrast, MTL→ventral PPC information flow was higher for successful, compared with unsuccessful, memory recall. Together, these results demonstrate that the effects of MTL stimulation are behaviorally, regionally, and directionally specific, that MTL stimulation selectively impairs directional signaling with PFC, and that causal MTL-ventral PPC circuits support successful memory recall. Findings provide new insights into dynamic casual circuits underling episodic memory and their modulation by MTL stimulation.SIGNIFICANCE STATEMENT The medial temporal lobe (MTL) and its interactions with prefrontal and parietal cortices (PFC and PPC) play a critical role in human memory. Dysfunctional MTL-PFC and MTL-PPC circuits are prominent in psychiatric and neurologic disorders, including Alzheimer's disease and schizophrenia. Brain stimulation has emerged as a potential mechanism for enhancing memory and cognitive functions, but the underlying neurophysiological mechanisms and dynamic causal circuitry underlying bottom-up and top-down signaling involving the MTL are unknown. Here, we use intracranial EEG recordings to investigate the effects of MTL stimulation on causal signaling in key episodic memory circuits linking the MTL with PFC and PPC. Our findings have implications for translational applications aimed at realizing the promise of brain stimulation-based treatment of memory disorders.


Assuntos
Mapeamento Encefálico , Memória Episódica , Feminino , Humanos , Mapeamento Encefálico/métodos , Córtex Pré-Frontal/fisiologia , Lobo Temporal/fisiologia , Lobo Parietal/fisiologia , Imageamento por Ressonância Magnética/métodos
13.
Dev Sci ; : e13524, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38695515

RESUMO

Number sense is fundamental to the development of numerical problem-solving skills. In early childhood, children establish associations between non-symbolic (e.g., a set of dots) and symbolic (e.g., Arabic numerals) representations of quantity. The developmental estrangement theory proposes that the relationship between non-symbolic and symbolic representations of quantity evolves with age, with increased dissociation across development. Consistent with this theory, recent research suggests that cross-format neural representational similarity (NRS) between non-symbolic and symbolic quantities is correlated with arithmetic fluency in children but not in adolescents. However, it is not known if short-term training (STT) can induce similar changes as long-term development. In this study, children aged 7-10 years underwent a theoretically motivated 4-week number sense training. Using multivariate neural pattern analysis, we investigated whether short-term learning could modify the relation between cross-format NRS and arithmetic skills. Our results revealed a significant correlation between cross-format NRS and arithmetic fluency in distributed brain regions, including the parietal and prefrontal cortices, prior to training. However, this association was no longer observed after training, and multivariate predictive models confirmed these findings. Our findings provide evidence that intensive STT during early childhood can promote behavioral improvements and neural plasticity that resemble and recapitulate long-term neurodevelopmental changes that occur from childhood to adolescence. More generally, our study contributes to our understanding of the malleability of number sense and highlights the potential for targeted interventions to shape neurodevelopmental trajectories in early childhood. RESEARCH HIGHLIGHTS: We tested the hypothesis that short-term number sense training induces the dissociation of symbolic numbers from non-symbolic representations of quantity in children. We leveraged a theoretically motivated intervention and multivariate pattern analysis to determine training-induced neurocognitive changes in the relation between number sense and arithmetic problem-solving skills. Neural representational similarity between non-symbolic and symbolic quantity representations was correlated with arithmetic skills before training but not after training. Short-term training recapitulates long-term neurodevelopmental changes associated with numerical problem-solving from childhood to adolescence.

14.
Dev Sci ; 27(4): e13489, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38421061

RESUMO

Abacus-based mental calculation (AMC) is a widely used educational tool for enhancing math learning, offering an accessible and cost-effective method for classroom implementation. Despite its universal appeal, the neurocognitive mechanisms that drive the efficacy of AMC training remain poorly understood. Notably, although abacus training relies heavily on the rapid recall of number positions and sequences, the role of memory systems in driving long-term AMC learning remains unknown. Here, we sought to address this gap by investigating the role of the medial temporal lobe (MTL) memory system in predicting long-term AMC training gains in second-grade children, who were longitudinally assessed up to fifth grade. Leveraging multimodal neuroimaging data, we tested the hypothesis that MTL systems, known for their involvement in associative memory, are instrumental in facilitating AMC-induced improvements in math skills. We found that gray matter volume in bilateral MTL, along with functional connectivity between the MTL and frontal and ventral temporal-occipital cortices, significantly predicted learning gains. Intriguingly, greater gray matter volume but weaker connectivity of the posterior parietal cortex predicted better learning outcomes, offering a more nuanced view of brain systems at play in AMC training. Our findings not only underscore the critical role of the MTL memory system in AMC training but also illuminate the neurobiological factors contributing to individual differences in cognitive skill acquisition. A video abstract of this article can be viewed at https://youtu.be/StVooNRc7T8. RESEARCH HIGHLIGHTS: We investigated the role of medial temporal lobe (MTL) memory system in driving children's math learning following abacus-based mental calculation (AMC) training. AMC training improved math skills in elementary school children across their second and fifth grade. MTL structural integrity and functional connectivity with prefrontal and ventral temporal-occipital cortices predicted long-term AMC training-related gains.


Assuntos
Aprendizagem , Lobo Temporal , Humanos , Lobo Temporal/fisiologia , Lobo Temporal/diagnóstico por imagem , Criança , Masculino , Feminino , Aprendizagem/fisiologia , Imageamento por Ressonância Magnética , Substância Cinzenta/fisiologia , Substância Cinzenta/diagnóstico por imagem , Matemática , Memória/fisiologia
15.
Cereb Cortex ; 33(3): 709-728, 2023 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-35296892

RESUMO

During social interactions, speakers signal information about their emotional state through their voice, which is known as emotional prosody. Little is known regarding the precise brain systems underlying emotional prosody decoding in children and whether accurate neural decoding of these vocal cues is linked to social skills. Here, we address critical gaps in the developmental literature by investigating neural representations of prosody and their links to behavior in children. Multivariate pattern analysis revealed that representations in the bilateral middle and posterior superior temporal sulcus (STS) divisions of voice-sensitive auditory cortex decode emotional prosody information in children. Crucially, emotional prosody decoding in middle STS was correlated with standardized measures of social communication abilities; more accurate decoding of prosody stimuli in the STS was predictive of greater social communication abilities in children. Moreover, social communication abilities were specifically related to decoding sadness, highlighting the importance of tuning in to negative emotional vocal cues for strengthening social responsiveness and functioning. Findings bridge an important theoretical gap by showing that the ability of the voice-sensitive cortex to detect emotional cues in speech is predictive of a child's social skills, including the ability to relate and interact with others.


Assuntos
Córtex Auditivo , Percepção da Fala , Voz , Humanos , Criança , Habilidades Sociais , Imageamento por Ressonância Magnética , Emoções , Comunicação
16.
Nano Lett ; 23(2): 422-428, 2023 Jan 25.
Artigo em Inglês | MEDLINE | ID: mdl-36602464

RESUMO

A broad effort is underway to understand and harness the interaction between superconductors and spin-active color centers with an eye on hybrid quantum devices and novel imaging modalities of superconducting materials. Most work, however, overlooks the interplay between either system and the environment created by the color center host. Here we use a diamond scanning probe to investigate the spin dynamics of a single nitrogen-vacancy (NV) center proximal to a superconducting film. We find that the presence of the superconductor increases the NV spin coherence lifetime, a phenomenon we tentatively rationalize as a change in the electric noise due to a superconductor-induced redistribution of charge carriers near induced redistribution of charge carriers near the NV. We then build on these findings to demonstrate transverse-relaxation-time-weighted imaging of the superconductor film. These results shed light on the dynamics governing the spin coherence of shallow NVs, and promise opportunities for new forms of noise spectroscopy and imaging of superconductors.

17.
J Neurosci ; 42(20): 4164-4173, 2022 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-35483917

RESUMO

The social worlds of young children primarily revolve around parents and caregivers, who play a key role in guiding children's social and cognitive development. However, a hallmark of adolescence is a shift in orientation toward nonfamilial social targets, an adaptive process that prepares adolescents for their independence. Little is known regarding neurobiological signatures underlying changes in adolescents' social orientation. Using functional brain imaging of human voice processing in children and adolescents (ages 7-16), we demonstrate distinct neural signatures for mother's voice and nonfamilial voices across child and adolescent development in reward and social valuation systems, instantiated in nucleus accumbens and ventromedial prefrontal cortex. While younger children showed greater activity in these brain systems for mother's voice compared with nonfamilial voices, older adolescents showed the opposite effect with increased activity for nonfamilial compared with mother's voice. Findings uncover a critical role for reward and social valuative brain systems in the pronounced changes in adolescents' orientation toward nonfamilial social targets. Our approach provides a template for examining developmental shifts in social reward and motivation in individuals with pronounced social impairments, including adolescents with autism.SIGNIFICANCE STATEMENT Children's social worlds undergo a transformation during adolescence. While socialization in young children revolves around parents and caregivers, adolescence is characterized by a shift in social orientation toward nonfamilial social partners. Here we show that this shift is reflected in neural activity measured from reward processing regions in response to brief vocal samples. When younger children hear their mother's voice, reward processing regions show greater activity compared with when they hear nonfamilial, unfamiliar voices. Strikingly, older adolescents show the opposite effect, with increased activity for nonfamilial compared with mother's voice. Findings identify the brain basis of adolescents' switch in social orientation toward nonfamilial social partners and provides a template for understanding neurodevelopment in clinical populations with social and communication difficulties.


Assuntos
Transtorno Autístico , Voz , Adolescente , Encéfalo/fisiologia , Criança , Pré-Escolar , Feminino , Humanos , Mães , Recompensa , Voz/fisiologia
18.
J Neurosci ; 42(19): 4000-4015, 2022 05 11.
Artigo em Inglês | MEDLINE | ID: mdl-35410879

RESUMO

The development of mathematical skills in early childhood relies on number sense, the foundational ability to discriminate among quantities. Number sense in early childhood is predictive of academic and professional success, and deficits in number sense are thought to underlie lifelong impairments in mathematical abilities. Despite its importance, the brain circuit mechanisms that support number sense learning remain poorly understood. Here, we designed a theoretically motivated training program to determine brain circuit mechanisms underlying foundational number sense learning in female and male elementary school-age children (7-10 years). Our 4 week integrative number sense training program gradually strengthened the understanding of the relations between symbolic (Arabic numerals) and nonsymbolic (sets of items) representations of quantity. We found that our number sense training program improved symbolic quantity discrimination ability in children across a wide range of math abilities including children with learning difficulties. Crucially, the strength of pretraining functional connectivity between the hippocampus and intraparietal sulcus, brain regions implicated in associative learning and quantity discrimination, respectively, predicted individual differences in number sense learning across typically developing children and children with learning difficulties. Reverse meta-analysis of interregional coactivations across 14,371 fMRI studies and 89 cognitive functions confirmed a reliable role for hippocampal-intraparietal sulcus circuits in learning. Our study identifies a canonical hippocampal-parietal circuit for learning that plays a foundational role in children's cognitive skill acquisition. Findings provide important insights into neurobiological circuit markers of individual differences in children's learning and delineate a robust target for effective cognitive interventions.SIGNIFICANCE STATEMENT Mathematical skill development relies on number sense, the ability to discriminate among quantities. Here, we develop a theoretically motivated training program and investigate brain circuits that predict number sense learning in children during a period important for acquisition of foundational cognitive skills. Our integrated number sense training program was effective in children across a wide a range of math abilities, including children with learning difficulties. We identify hippocampal-parietal circuits that predict individual differences in learning gains. Our study identifies a brain circuit critical for the acquisition of foundational cognitive skills, which will be useful for developing effective interventions to remediate learning disabilities.


Assuntos
Cognição , Resolução de Problemas , Criança , Pré-Escolar , Feminino , Hipocampo , Humanos , Masculino , Matemática , Lobo Parietal
19.
Int J Obes (Lond) ; 47(11): 1161-1170, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37674032

RESUMO

BACKGROUND: Endoscopic sleeve gastroplasty (ESG) is a minimally invasive procedure that has been demonstrated in the MERIT randomised, controlled trial to result in substantial and durable additional weight loss in adults with obesity compared with lifestyle modification (LM) alone. We sought to conduct the first cost-effectiveness analysis of ESG versus LM alone in adults with class II obesity (BMI 35.0-39.9 kg/m2) from a national healthcare system perspective in England based on results from this study. METHODS: A 6-state Markov model was developed comprising 5 BMI-based health states and an absorbing death state. Baseline characteristics, utilities, and transition probabilities were informed by patient-level data from the subset of patients with class II obesity in MERIT. Adverse events (AEs) were based on the MERIT safety population. Mortality was estimated by applying BMI-specific hazard ratios from the published literature to UK general population mortality rates. Utilities for the healthy weight and overweight health states were informed from the literature; disutility associated with increasing BMI in the class I-III obesity health states was estimated using MERIT utility data. Disutility due to AEs and the prevalence of obesity-related comorbidities were based on the literature. Costs included intervention costs, AE costs, and comorbidity costs. RESULTS: ESG resulted in higher overall costs than LM alone but led to an increase in quality-adjusted life years (QALYs). The incremental cost-effectiveness ratio (ICER) for ESG vs LM alone was £2453/QALY gained. ESG was consistently cost effective across a wide range of sensitivity analyses, with no ICER estimate exceeding £10,000/QALY gained. In probabilistic sensitivity analysis, the mean ICER was £2502/QALY gained and ESG remained cost effective in 98.25% of iterations at a willingness-to-pay threshold of £20,000/QALY. CONCLUSION: Our study indicates that ESG is highly cost effective versus LM alone for the treatment of adults with class II obesity in England.


Assuntos
Gastroplastia , Humanos , Adulto , Análise de Custo-Efetividade , Análise Custo-Benefício , Obesidade/epidemiologia , Obesidade/cirurgia , Estilo de Vida , Reino Unido/epidemiologia , Anos de Vida Ajustados por Qualidade de Vida
20.
Brain ; 145(11): 4042-4055, 2022 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-35357463

RESUMO

Dopaminergic medication is widely used to alleviate motor symptoms of Parkinson's disease, but these medications also impact cognition with significant variability across patients. It is hypothesized that dopaminergic medication impacts cognition and working memory in Parkinson's disease by modulating frontoparietal-basal ganglia cognitive control circuits, but little is known about the underlying causal signalling mechanisms and their relation to individual differences in response to dopaminergic medication. Here we use a novel state-space computational model with ultra-fast (490 ms resolution) functional MRI to investigate dynamic causal signalling in frontoparietal-basal ganglia circuits associated with working memory in 44 Parkinson's disease patients ON and OFF dopaminergic medication, as well as matched 36 healthy controls. Our analysis revealed aberrant causal signalling in frontoparietal-basal ganglia circuits in Parkinson's disease patients OFF medication. Importantly, aberrant signalling was normalized by dopaminergic medication and a novel quantitative distance measure predicted individual differences in cognitive change associated with medication in Parkinson's disease patients. These findings were specific to causal signalling measures, as no such effects were detected with conventional non-causal connectivity measures. Our analysis also identified a specific frontoparietal causal signalling pathway from right middle frontal gyrus to right posterior parietal cortex that is impaired in Parkinson's disease. Unlike in healthy controls, the strength of causal interactions in this pathway did not increase with working memory load and the strength of load-dependent causal weights was not related to individual differences in working memory task performance in Parkinson's disease patients OFF medication. However, dopaminergic medication in Parkinson's disease patients reinstated the relation with working memory performance. Our findings provide new insights into aberrant causal brain circuit dynamics during working memory and identify mechanisms by which dopaminergic medication normalizes cognitive control circuits.


Assuntos
Doença de Parkinson , Humanos , Doença de Parkinson/complicações , Doença de Parkinson/tratamento farmacológico , Dopaminérgicos/uso terapêutico , Gânglios da Base , Cognição/fisiologia , Imageamento por Ressonância Magnética
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