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1.
Nature ; 594(7862): 201-206, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-34108694

RESUMO

The performance of light microscopes is limited by the stochastic nature of light, which exists in discrete packets of energy known as photons. Randomness in the times that photons are detected introduces shot noise, which fundamentally constrains sensitivity, resolution and speed1. Although the long-established solution to this problem is to increase the intensity of the illumination light, this is not always possible when investigating living systems, because bright lasers can severely disturb biological processes2-4. Theory predicts that biological imaging may be improved without increasing light intensity by using quantum photon correlations1,5. Here we experimentally show that quantum correlations allow a signal-to-noise ratio beyond the photodamage limit of conventional microscopy. Our microscope is a coherent Raman microscope that offers subwavelength resolution and incorporates bright quantum correlated illumination. The correlations allow imaging of molecular bonds within a cell with a 35 per cent improved signal-to-noise ratio compared with conventional microscopy, corresponding to a 14 per cent improvement in concentration sensitivity. This enables the observation of biological structures that would not otherwise be resolved. Coherent Raman microscopes allow highly selective biomolecular fingerprinting in unlabelled specimens6,7, but photodamage is a major roadblock for many applications8,9. By showing that the photodamage limit can be overcome, our work will enable order-of-magnitude improvements in the signal-to-noise ratio and the imaging speed.


Assuntos
Lasers , Iluminação , Microscopia/métodos , Fótons , Teoria Quântica , Análise Espectral Raman , Células/patologia , Células/efeitos da radiação , Lasers/efeitos adversos , Iluminação/efeitos adversos , Microscopia/instrumentação , Fótons/efeitos adversos , Razão Sinal-Ruído , Análise Espectral Raman/instrumentação , Análise Espectral Raman/métodos
2.
Chem Rev ; 123(16): 9786-9879, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37552606

RESUMO

When molecules are coupled to an optical cavity, new light-matter hybrid states, so-called polaritons, are formed due to quantum light-matter interactions. With the experimental demonstrations of modifying chemical reactivities by forming polaritons under strong light-matter interactions, theorists have been encouraged to develop new methods to simulate these systems and discover new strategies to tune and control reactions. This review summarizes some of these exciting theoretical advances in polariton chemistry, in methods ranging from the fundamental framework to computational techniques and applications spanning from photochemistry to vibrational strong coupling. Even though the theory of quantum light-matter interactions goes back to the midtwentieth century, the gaps in the knowledge of molecular quantum electrodynamics (QED) have only recently been filled. We review recent advances made in resolving gauge ambiguities, the correct form of different QED Hamiltonians under different gauges, and their connections to various quantum optics models. Then, we review recently developed ab initio QED approaches which can accurately describe polariton states in a realistic molecule-cavity hybrid system. We then discuss applications using these method advancements. We review advancements in polariton photochemistry where the cavity is made resonant to electronic transitions to control molecular nonadiabatic excited state dynamics and enable new photochemical reactivities. When the cavity resonance is tuned to the molecular vibrations instead, ground-state chemical reaction modifications have been demonstrated experimentally, though its mechanistic principle remains unclear. We present some recent theoretical progress in resolving this mystery. Finally, we review the recent advances in understanding the collective coupling regime between light and matter, where many molecules can collectively couple to a single cavity mode or many cavity modes. We also lay out the current challenges in theory to explain the observed experimental results. We hope that this review will serve as a useful document for anyone who wants to become familiar with the context of polariton chemistry and molecular cavity QED and thus significantly benefit the entire community.

3.
J Phys Chem A ; 127(32): 6830-6841, 2023 Aug 17.
Artigo em Inglês | MEDLINE | ID: mdl-37499090

RESUMO

We provide a simple and intuitive theory to explain how coupling a molecule to an optical cavity can modify ground-state chemical reactivity by exploiting intrinsic quantum behaviors of light-matter interactions. Using the recently developed polarized Fock states representation, we demonstrate that the change of the ground-state potential is achieved due to the scaling of diabatic electronic couplings with the overlap of the polarized Fock states. Our theory predicts that for a proton-transfer model system, the ground-state barrier height can be modified through light-matter interactions when the cavity frequency is in the electronic excitation range. Our simple theory explains several recent computational investigations that discovered the same effect. We further demonstrate that under the deep strong coupling limit of the light and matter, the polaritonic ground and first excited eigenstates become the Mulliken-Hush diabatic states, which are the eigenstates of the dipole operator. This work provides a simple but powerful theoretical framework to understand how strong coupling between the molecule and the cavity can modify ground-state reactivities.

4.
Opt Lett ; 47(6): 1446-1449, 2022 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-35290335

RESUMO

This work provides the fundamental theoretical framework for few-mode cavity quantum electrodynamics by resolving the gauge ambiguities between the Coulomb gauge and the dipole gauge Hamiltonians under the photonic mode truncation. We first propose a general framework to resolve ambiguities for an arbitrary truncation in a given gauge. Then, we specifically consider the case of mode truncation, deriving gauge invariant expressions for both the Coulomb and dipole gauge Hamiltonians that naturally reduce to the commonly used single-mode Hamiltonians when considering a single-mode truncation. We finally provide the analytical and numerical results of both atomic and molecular model systems coupled to the cavity to demonstrate the validity of our theory.

6.
Issues Law Med ; 37(2): 129-164, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36629763

RESUMO

The U.S. Roman Catholic bishops have been earnest participants in the contemporary public policy debate on abortion. This article reviews the bishops' main policy documents in which the Church's teaching on abortion is applied, first, within the context of the debate on abortion policy that was underway in the states before Roe v. Wade, and, second, within the grave and challenging situation thereafter when a right to abortion was made the law of the land. Whether discussing court cases, statutory law, human life bills, or various proposals to amend the Constitution, the bishops raised up a broad vision of full protection in law for all human beings, born and unborn, and promoted a comprehensive program of education, pastoral care, public policy, and prayer. Building off this review the article concludes with some initial reflections on the Dobbs world in which the Court has returned the abortion issue to the people and their elected representatives.


Assuntos
Aborto Induzido , Catolicismo , Gravidez , Feminino , Humanos , Estados Unidos , Política Pública , Aborto Legal
7.
J Neurosci ; 40(21): 4130-4144, 2020 05 20.
Artigo em Inglês | MEDLINE | ID: mdl-32277044

RESUMO

Information about water flow, detected by lateral line organs, is critical to the behavior and survival of fish and amphibians. While certain aspects of water flow processing have been revealed through electrophysiology, we lack a comprehensive description of the neurons that respond to water flow and the network that they form. Here, we use brain-wide calcium imaging in combination with microfluidic stimulation to map out, at cellular resolution, neuronal responses involved in perceiving and processing water flow information in larval zebrafish. We find a diverse array of neurons responding to head-to-tail (h-t) flow, tail-to-head (t-h) flow, or both. Early in this pathway, in the lateral line ganglia, neurons respond almost exclusively to the simple presence of h-t or t-h flow, but later processing includes neurons responding specifically to flow onset, representing the accumulated displacement of flow during a stimulus, or encoding the speed of the flow. The neurons reporting on these more nuanced details are located across numerous brain regions, including some not previously implicated in water flow processing. A graph theory-based analysis of the brain-wide water flow network shows that a majority of this processing is dedicated to h-t flow detection, and this is reinforced by our finding that details like flow velocity and the total accumulated flow are only encoded for the h-t direction. The results represent the first brain-wide description of processing for this important modality, and provide a departure point for more detailed studies of the flow of information through this network.SIGNIFICANCE STATEMENT In aquatic animals, the lateral line is important for detecting water flow stimuli, but the brain networks that interpret this information remain mysterious. Here, we have imaged the activity of individual neurons across the entire brains of larval zebrafish, revealing all response types and their brain locations as water flow processing occurs. We find neurons that respond to the simple presence of water flow, and others attuned to the direction, speed, and duration of flow, or the accumulated displacement of water that has passed during the stimulus. With this information, we modeled the underlying network, describing a system that is nuanced in its processing of water flow simulating head-to-tail motion but rudimentary in processing flow in the tail-to-head direction.


Assuntos
Encéfalo/fisiologia , Sistema da Linha Lateral/fisiologia , Percepção de Movimento/fisiologia , Neurônios/fisiologia , Animais , Microfluídica , Água , Peixe-Zebra
8.
BMC Biol ; 18(1): 125, 2020 09 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938458

RESUMO

BACKGROUND: Loss or disrupted expression of the FMR1 gene causes fragile X syndrome (FXS), the most common monogenetic form of autism in humans. Although disruptions in sensory processing are core traits of FXS and autism, the neural underpinnings of these phenotypes are poorly understood. Using calcium imaging to record from the entire brain at cellular resolution, we investigated neuronal responses to visual and auditory stimuli in larval zebrafish, using fmr1 mutants to model FXS. The purpose of this study was to model the alterations of sensory networks, brain-wide and at cellular resolution, that underlie the sensory aspects of FXS and autism. RESULTS: Combining functional analyses with the neurons' anatomical positions, we found that fmr1-/- animals have normal responses to visual motion. However, there were several alterations in the auditory processing of fmr1-/- animals. Auditory responses were more plentiful in hindbrain structures and in the thalamus. The thalamus, torus semicircularis, and tegmentum had clusters of neurons that responded more strongly to auditory stimuli in fmr1-/- animals. Functional connectivity networks showed more inter-regional connectivity at lower sound intensities (a - 3 to - 6 dB shift) in fmr1-/- larvae compared to wild type. Finally, the decoding capacities of specific components of the ascending auditory pathway were altered: the octavolateralis nucleus within the hindbrain had significantly stronger decoding of auditory amplitude while the telencephalon had weaker decoding in fmr1-/- mutants. CONCLUSIONS: We demonstrated that fmr1-/- larvae are hypersensitive to sound, with a 3-6 dB shift in sensitivity, and identified four sub-cortical brain regions with more plentiful responses and/or greater response strengths to auditory stimuli. We also constructed an experimentally supported model of how auditory information may be processed brain-wide in fmr1-/- larvae. Our model suggests that the early ascending auditory pathway transmits more auditory information, with less filtering and modulation, in this model of FXS.


Assuntos
Transtorno Autístico/fisiopatologia , Encéfalo/fisiopatologia , Síndrome do Cromossomo X Frágil/fisiopatologia , Peixe-Zebra , Animais , Transtorno Autístico/genética , Modelos Animais de Doenças , Síndrome do Cromossomo X Frágil/genética
9.
Phys Rev Lett ; 125(12): 123602, 2020 Sep 18.
Artigo em Inglês | MEDLINE | ID: mdl-33016745

RESUMO

This work provides the fundamental theoretical framework for molecular cavity quantum electrodynamics by resolving the gauge ambiguities between the Coulomb gauge and the dipole gauge Hamiltonians under the electronic state truncation. We conjecture that such ambiguity arises because not all operators are consistently constrained in the same truncated electronic subspace for both gauges. We resolve this ambiguity by constructing a unitary transformation operator that properly constrains all light-matter interaction terms in the same subspace. We further derive an equivalent and yet convenient expression for the Coulomb gauge Hamiltonian under the truncated subspace. We finally provide the analytical and numerical results of a model molecular system coupled to the cavity to demonstrate the validity of our theory.

10.
J Child Sex Abus ; 29(1): 90-111, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31219778

RESUMO

Child sexual abuse (CSA) is a common problem, and allegations of CSA require a thorough multidisciplinary investigation which includes a comprehensive medical evaluation. Although most CSA victims will have normal exams, some will have physical injuries, sexually transmitted infections (STIs), and/or other problems. We are reporting the results of the examinations of 573 children evaluated in the West Alabama Child Medical Evaluation Program (WACMEP). This is the first report of CSA exams coming from Alabama and one of a few from a smaller medical center. Most were victimized by a single, older male perpetrator who was known to the family, often related, and had unsupervised access to the child. One-fourth (24.1%) of the children had significant exam findings, including 7.5% with a STI. Females were more likely to have significant findings including most of the STIs. Other historical factors statistically linked to an increased risk of having significant exam findings included being African-American, providing a clear history of abuse, and/or reporting vulvar pain or vaginal symptoms such as discharge, itching, or bleeding. The incidence of significant findings including STIs was similar to previously reported studies from larger urban centers across the United States, United Kingdom, and New Zealand.


Assuntos
Abuso Sexual na Infância/diagnóstico , Abuso Sexual na Infância/estatística & dados numéricos , Prontuários Médicos , Exame Físico , Alabama/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Estudos Retrospectivos , Infecções Sexualmente Transmissíveis/diagnóstico , Infecções Sexualmente Transmissíveis/epidemiologia
11.
Cancer ; 120(9): 1433-40, 2014 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-24877167

RESUMO

BACKGROUND: The objective of this trial was to determine how a mucoadhesive hydrogel (MuGard), a marketed medical device, would fare when tested with the strictness of a conventional multi-institutional, double-blind, randomized, placebo-controlled study format. METHODS: A total of 120 subjects planned to receive chemoradiation therapy (CRT) for treatment of head and neck cancers were randomized to receive either MuGard or sham control rinse (SC) during CRT. Subjects completed the validated Oral Mucositis Daily Questionnaire. Weight, opiate use, and World Health Organization (WHO) oral mucositis (OM) scores were recorded. Subjects who dosed at least once daily during the first 2.5 weeks of CRT were included in the efficacy analysis. RESULTS: Of 120 subjects enrolled, 78 (SC, N=41; MuGard, N=37) were eligible for efficacy analysis. Both cohorts were similar in demographics, baseline characteristics, primary tumor type, and planned CRT regimen. MuGard effectively mitigated OM symptoms as reflected by area under the curve of daily patient-reported oral soreness (P=.034) and WHO scores on the last day of radiation therapy (P=.038). MuGard was also associated with nonsignificant trends related to therapeutic benefit including opioid use duration, and OM scores (WHO criteria) at CRT week 4. Rinse compliance was identical between cohorts. No significant adverse events were reported, and the adverse event incidence was similar between cohorts. CONCLUSIONS: Testing MuGard, a rinse marketed as a device, in a standard clinical trial format demonstrated its superiority to SC in mitigating OM symptoms, delaying OM progression, and its safety and tolerability.


Assuntos
Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/radioterapia , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/radioterapia , Hidrogel de Polietilenoglicol-Dimetacrilato/administração & dosagem , Estomatite/tratamento farmacológico , Estomatite/etiologia , Adulto , Idoso , Idoso de 80 Anos ou mais , Carcinoma de Células Escamosas/patologia , Quimiorradioterapia/efeitos adversos , Método Duplo-Cego , Feminino , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Masculino , Pessoa de Meia-Idade , Mucosa Bucal/efeitos dos fármacos , Mucosa Bucal/patologia , Mucosa Bucal/efeitos da radiação , Estadiamento de Neoplasias , Placebos , Carcinoma de Células Escamosas de Cabeça e Pescoço
12.
Sci Rep ; 14(1): 10387, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38710717

RESUMO

Tropical Small Island Developing States (SIDS), such as those in the Caribbean, are among the most vulnerable to the impacts of climate change, most notably sea-level rise. The current sea-level rise in the Caribbean is 3.40 ± 0.3 mm/year (1993-2019), which is similar to the 3.25 ± 0.4 mm/year global mean sea-level (GMSL) rise (1993-2018). Throughout the year, Caribbean seasonal sea-level variability is found to respond to sea surface temperature variability. Over the past few decades, the trend in Caribbean Sea-level rise is also found to be variable. Satellite altimetry and steric sea-level records of the Caribbean region reveal a shift in the late 2003-early 2004, which separates two distinct periods of sea-level rise. Thermal expansion dominates the sea-level trend from 1993-2003. Following this period, there is an increased trend in sea-level rise, with a dominance of mass changes from 2004-2019, as confirmed by GRACE data. During this period, the sea-level trend is 6.15 ± 0.5 mm/year, which is 67% faster than the most recent estimates of global mean sea-level rise provided by the Intergovernmental Panel on Climate Change (3.69 ± 0.5 mm/year for the period 2006-2018). Despite its reduced importance, increasing temperatures contribute greatly to sea-level rise in the Caribbean region through thermal expansion of ocean water, hence there is a need to limit the current trend of global warming.

13.
Biomater Sci ; 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39268757

RESUMO

Confocal reflectance imaging typically suffers from high background and poor sensitivity. We demonstrate sensitive and low-background reflectance imaging of cells encapsulated in transparent 3D hydrogels. Nanoscale cell morphology is visualized with sensitivity similar to confocal fluorescence, with low laser power, minimal specimen preparation, and reduced toxicity.

14.
JAMA Netw Open ; 7(9): e2431967, 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39287948

RESUMO

Importance: The degree of cancer patients' financial hardship is dynamic and can change over time. Objective: To assess longitudinal changes in financial hardship among patients with early-stage colorectal cancer. Design, Setting, and Participants: In this prospective longitudinal cohort study, English-speaking adult patients with a new diagnosis of stage I to III colorectal cancer being treated with curative intent at National Cancer Institute (NCI) Community Oncology Research Program (NCORP) practices between May 2018 and July 2020 and who had not started chemotherapy and/or radiation were included. Data analysis was conducted from March to December 2023. Main Outcomes and Measures: Patients completed surveys at baseline as well as at 3, 6, 12, and 24 months after enrollment. Cost-related care nonadherence and material hardship, as adopted by Medical Expenditure Panel Survey, were measured. Factors associated with financial hardship were assessed using longitudinal multivariable logistic regression models with time interaction. Results: A total of 451 patients completed baseline questions, with 217 (48.1%) completing the 24-month follow-up. Mean (SD) age was 61.0 (12.0) years (210 [46.6%] female; 33 [7.3%] Black, 380 [84.3%] White, and 33 [7.3%] American Indian or Alaska Native, Asian, multiracial, or Native Hawaiian or Other Pacific Islander individuals or those who did not report race or who had unknown race). Among 217 patients with data at baseline and 24 months, 19 (8.8%) reported cost-related care nonadherence at baseline vs 20 (9.2%) at 24 months (P = .84), and 125 (57.6%) reported material hardship at baseline vs 76 (35.0%) at 24 months (P < .001). In multivariable analysis, lower financial worry (odds ratio [OR], 0.90; 95% CI, 0.87-0.93), higher education (OR, 0.34; 95% CI, 0.15-0.77), and older age (OR, 0.94; 95% CI, 0.91-0.98) were associated with lower nonadherence. Receipt of chemotherapy was associated with higher material hardship (OR, 2.68; 95% CI, 1.15-6.29), while lower financial worry was associated with lower material hardship (OR, 0.83; 95% CI, 0.80-0.96). Over 24 months, female sex was associated with lower nonadherence (OR, 0.90; 95% CI, 0.85-0.96), while higher education was associated with higher nonadherence (OR, 1.09; 95% CI, 1.03-1.17). Being employed was associated with lower material hardship (OR, 0.85; 95% CI, 0.78-0.93), while receipt of care at safety-net hospitals was associated with higher hardship (OR, 1.09; 95% CI, 1.01-1.17). Conclusions and Relevance: In patients with early-stage colorectal cancer, material hardship was more common than cost-related cancer care nonadherence and decreased over time, while nonadherence remained unchanged. Early and longitudinal financial screening and referral to intervention are recommended to mitigate financial hardship.


Assuntos
Neoplasias Colorretais , Estresse Financeiro , Humanos , Feminino , Neoplasias Colorretais/terapia , Neoplasias Colorretais/economia , Masculino , Pessoa de Meia-Idade , Estudos Longitudinais , Estudos Prospectivos , Idoso , Estados Unidos , Estadiamento de Neoplasias , Gastos em Saúde/estatística & dados numéricos , Inquéritos e Questionários
15.
Opt Express ; 21(7): 8018-24, 2013 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-23571892

RESUMO

We demonstrate a lock-in particle tracking scheme in optical tweezers based on stroboscopic modulation of an illuminating optical field. This scheme is found to evade low frequency noise sources while otherwise producing an equivalent position measurement to continuous measurement. This was demonstrated to yield up to 20 dB of noise suppression at both low frequencies (< 1 kHz), where low frequency electronic noise was significant, and around 630 kHz where laser relaxation oscillations introduced laser noise. The setup is simple, and compatible with any trapping optics.


Assuntos
Iluminação/instrumentação , Imagem Molecular/instrumentação , Pinças Ópticas , Estroboscopia/instrumentação , Desenho de Equipamento , Análise de Falha de Equipamento
16.
Opt Lett ; 38(11): 1915-7, 2013 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-23722788

RESUMO

We present the characterization of the recently developed cavity enhanced amplitude modulation laser absorption spectroscopy (CEAMLAS) technique to measure dissipation within the evanescent field of a whispering-gallery mode resonator, and demonstrate the parallel use of CEAMLAS and the Pound-Drever-Hall measurement techniques to provide both dissipation and dispersive real-time microresonator measurements. Using an atomic force microscope tip, we introduce a controlled perturbation to the evanescent field of the resonator. In this case, dissipative sensing allows up to 16.8 dB sensitivity improvement over dispersive measurements, providing the possibility for enhanced sensitivity in application such as biomolecule detection.

17.
Appl Opt ; 52(23): 5718-23, 2013 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-23938424

RESUMO

Dark-field microscopy is a well-known technique used to exclude the bright background of unscattered photons from a measurement. We show that by choosing an appropriate illumination angle, the background of unwanted scattered light can also be suppressed. The collected flux of scattered photons is calculated in the Mie scattering regime for various particle sizes and objectives over a range of illumination angles. In the case that the dark-field measurement is limited by background scattering, we find that the sensitivity can be improved by lowering the objective numerical aperture. The collected photon flux is calculated for an exemplary dark-field microscopy experiment in which lipid granules were studied within yeast cells. Our model suggests that the signal-to-noise ratio was over three-orders-of-magnitude higher than it would have been with an equivalent bright-field setup.

18.
Opt Express ; 20(12): 12742-51, 2012 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-22714303

RESUMO

Cavity optoelectromechanical regenerative amplification is demonstrated. An optical cavity enhances mechanical transduction, allowing sensitive measurement even for heavy oscillators. A 27.3 MHz mechanical mode of a microtoroid was linewidth narrowed to 6.6 ± 1.4 mHz, 30 times smaller than previously achieved with radiation pressure driving in such a system. These results may have applications in areas such as ultrasensitive optomechanical mass spectroscopy.

19.
Opt Express ; 20(11): 12622-30, 2012 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-22714249

RESUMO

We present a laser amplitude modulation technique to actively stabilize the critical coupling of a microresonator by controlling the evanescent coupling gap from an optical fiber taper. It is a form of nulled lock-in detection, which decouples laser intensity fluctuations from the critical coupling measurement. We achieved a stabilization bandwidth of ∼ 20 Hz, with up to 5 orders of magnitude displacement noise suppression at 10 mHz, and an inferred gap stability of better than a picometer/√Hz.


Assuntos
Desenho Assistido por Computador , Tecnologia de Fibra Óptica/instrumentação , Lasers , Modelos Teóricos , Refratometria/instrumentação , Ressonância de Plasmônio de Superfície/instrumentação , Simulação por Computador , Desenho de Equipamento , Análise de Falha de Equipamento , Luz , Espalhamento de Radiação
20.
Nat Commun ; 13(1): 895, 2022 02 16.
Artigo em Inglês | MEDLINE | ID: mdl-35173170

RESUMO

Habituation is a form of learning during which animals stop responding to repetitive stimuli, and deficits in habituation are characteristic of several psychiatric disorders. Due to technical challenges, the brain-wide networks mediating habituation are poorly understood. Here we report brain-wide calcium imaging during larval zebrafish habituation to repeated visual looming stimuli. We show that different functional categories of loom-sensitive neurons are located in characteristic locations throughout the brain, and that both the functional properties of their networks and the resulting behavior can be modulated by stimulus saliency and timing. Using graph theory, we identify a visual circuit that habituates minimally, a moderately habituating midbrain population proposed to mediate the sensorimotor transformation, and downstream circuit elements responsible for higher order representations and the delivery of behavior. Zebrafish larvae carrying a mutation in the fmr1 gene have a systematic shift toward sustained premotor activity in this network, and show slower behavioral habituation.


Assuntos
Habituação Psicofisiológica/fisiologia , Mesencéfalo/fisiologia , Proteínas de Ligação a RNA/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/fisiologia , Animais , Animais Geneticamente Modificados , Ondas Encefálicas/fisiologia , Cálcio/análise , Larva/fisiologia , Neurônios/fisiologia , Proteínas de Ligação a RNA/genética , Reflexo de Sobressalto/fisiologia , Peixe-Zebra/embriologia , Proteínas de Peixe-Zebra/genética
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