Project acronym 2STEPPARKIN
Project A novel two-step model for neurodegeneration in Parkinson’s disease
Researcher (PI) Emi Nagoshi
Host Institution (HI) UNIVERSITE DE GENEVE
Call Details Starting Grant (StG), LS5, ERC-2012-StG_20111109
Summary Parkinson’s disease (PD) is the second most common neurodegenerative disorder primarily caused by the progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN). Despite the advances in gene discovery associated with PD, the knowledge of the PD pathogenesis is largely limited to the involvement of these genes in the generic cell death pathways, and why degeneration is specific to DA neurons and why the degeneration is progressive remain enigmatic. Broad goal of our work is therefore to elucidate the mechanisms underlying specific and progressive DA neuron degeneration in PD. Our new Drosophila model of PD ⎯Fer2 gene loss-of-function mutation⎯ is unusually well suited to address these questions. Fer2 mutants exhibit specific and progressive death of brain DA neurons as well as severe locomotor defects and short life span. Strikingly, the death of DA neuron is initiated in a small cluster of Fer2-expressing DA neurons and subsequently propagates to Fer2-negative DA neurons. We therefore propose a novel two-step model of the neurodegeneration in PD: primary cell death occurs in a specific subset of dopamindegic neurons that are genetically defined, and subsequently the failure of the neuronal connectivity triggers and propagates secondary cell death to remaining DA neurons. In this research, we will test this hypothesis and investigate the underlying molecular mechanisms. This will be the first study to examine circuit-dependency in DA neuron degeneration. Our approach will use a combination of non-biased genomic techniques and candidate-based screening, in addition to the powerful Drosophila genetic toolbox. Furthermore, to test this hypothesis beyond the Drosophila model, we will establish new mouse models of PD that exhibit progressive DA neuron degeneration. Outcome of this research will likely revolutionize the understanding of PD pathogenesis and open an avenue toward the discovery of effective therapy strategies against PD.
Summary
Parkinson’s disease (PD) is the second most common neurodegenerative disorder primarily caused by the progressive loss of dopaminergic (DA) neurons in the substantia nigra (SN). Despite the advances in gene discovery associated with PD, the knowledge of the PD pathogenesis is largely limited to the involvement of these genes in the generic cell death pathways, and why degeneration is specific to DA neurons and why the degeneration is progressive remain enigmatic. Broad goal of our work is therefore to elucidate the mechanisms underlying specific and progressive DA neuron degeneration in PD. Our new Drosophila model of PD ⎯Fer2 gene loss-of-function mutation⎯ is unusually well suited to address these questions. Fer2 mutants exhibit specific and progressive death of brain DA neurons as well as severe locomotor defects and short life span. Strikingly, the death of DA neuron is initiated in a small cluster of Fer2-expressing DA neurons and subsequently propagates to Fer2-negative DA neurons. We therefore propose a novel two-step model of the neurodegeneration in PD: primary cell death occurs in a specific subset of dopamindegic neurons that are genetically defined, and subsequently the failure of the neuronal connectivity triggers and propagates secondary cell death to remaining DA neurons. In this research, we will test this hypothesis and investigate the underlying molecular mechanisms. This will be the first study to examine circuit-dependency in DA neuron degeneration. Our approach will use a combination of non-biased genomic techniques and candidate-based screening, in addition to the powerful Drosophila genetic toolbox. Furthermore, to test this hypothesis beyond the Drosophila model, we will establish new mouse models of PD that exhibit progressive DA neuron degeneration. Outcome of this research will likely revolutionize the understanding of PD pathogenesis and open an avenue toward the discovery of effective therapy strategies against PD.
Max ERC Funding
1 518 960 €
Duration
Start date: 2013-06-01, End date: 2018-05-31
Project acronym 3D-FIREFLUC
Project Taming the particle transport in magnetized plasmas via perturbative fields
Researcher (PI) Eleonora VIEZZER
Host Institution (HI) UNIVERSIDAD DE SEVILLA
Call Details Starting Grant (StG), PE2, ERC-2018-STG
Summary Wave-particle interactions are ubiquitous in nature and play a fundamental role in astrophysical and fusion plasmas. In solar plasmas, magnetohydrodynamic (MHD) fluctuations are thought to be responsible for the heating of the solar corona and the generation of the solar wind. In magnetically confined fusion (MCF) devices, enhanced particle transport induced by MHD fluctuations can deteriorate the plasma confinement, and also endanger the device integrity. MCF devices are an ideal testbed to verify current models and develop mitigation / protection techniques.
The proposed project paves the way for providing active control techniques to tame the MHD induced particle transport in a fusion plasma. A solid understanding of the interaction between energetic particles and MHD instabilities in the presence of electric fields and plasma currents is required to develop such techniques. I will pursue this goal through innovative diagnosis techniques with unprecedented spatio-temporal resolution. Combined with state-of-the-art hybrid MHD codes, a deep insight into the underlying physics mechanism will be gained. The outcome of this research project will have a major impact for next-step MCF devices as I will provide ground-breaking control techniques for mitigating MHD induced particle transport in magnetized plasmas.
The project consists of 3 research lines which follow a bottom-up approach:
(1) Cutting-edge instrumentation, aiming at the new generation of energetic particle and edge current diagnostics.
(2) Unravel the dynamics of energetic particles, electric fields, edge currents and MHD fluctuations.
(3) From lab to space weather: The developed models will revolutionize our understanding of the observed particle acceleration and transport in the solar corona.
Based on this approach, the project represents a gateway between the fusion, astrophysics and space communities opening new avenues for a common basic understanding.
Summary
Wave-particle interactions are ubiquitous in nature and play a fundamental role in astrophysical and fusion plasmas. In solar plasmas, magnetohydrodynamic (MHD) fluctuations are thought to be responsible for the heating of the solar corona and the generation of the solar wind. In magnetically confined fusion (MCF) devices, enhanced particle transport induced by MHD fluctuations can deteriorate the plasma confinement, and also endanger the device integrity. MCF devices are an ideal testbed to verify current models and develop mitigation / protection techniques.
The proposed project paves the way for providing active control techniques to tame the MHD induced particle transport in a fusion plasma. A solid understanding of the interaction between energetic particles and MHD instabilities in the presence of electric fields and plasma currents is required to develop such techniques. I will pursue this goal through innovative diagnosis techniques with unprecedented spatio-temporal resolution. Combined with state-of-the-art hybrid MHD codes, a deep insight into the underlying physics mechanism will be gained. The outcome of this research project will have a major impact for next-step MCF devices as I will provide ground-breaking control techniques for mitigating MHD induced particle transport in magnetized plasmas.
The project consists of 3 research lines which follow a bottom-up approach:
(1) Cutting-edge instrumentation, aiming at the new generation of energetic particle and edge current diagnostics.
(2) Unravel the dynamics of energetic particles, electric fields, edge currents and MHD fluctuations.
(3) From lab to space weather: The developed models will revolutionize our understanding of the observed particle acceleration and transport in the solar corona.
Based on this approach, the project represents a gateway between the fusion, astrophysics and space communities opening new avenues for a common basic understanding.
Max ERC Funding
1 512 250 €
Duration
Start date: 2019-05-01, End date: 2024-04-30
Project acronym 3D-QUEST
Project 3D-Quantum Integrated Optical Simulation
Researcher (PI) Fabio Sciarrino
Host Institution (HI) UNIVERSITA DEGLI STUDI DI ROMA LA SAPIENZA
Call Details Starting Grant (StG), PE2, ERC-2012-StG_20111012
Summary "Quantum information was born from the merging of classical information and quantum physics. Its main objective consists of understanding the quantum nature of information and learning how to process it by using physical systems which operate by following quantum mechanics laws. Quantum simulation is a fundamental instrument to investigate phenomena of quantum systems dynamics, such as quantum transport, particle localizations and energy transfer, quantum-to-classical transition, and even quantum improved computation, all tasks that are hard to simulate with classical approaches. Within this framework integrated photonic circuits have a strong potential to realize quantum information processing by optical systems.
The aim of 3D-QUEST is to develop and implement quantum simulation by exploiting 3-dimensional integrated photonic circuits. 3D-QUEST is structured to demonstrate the potential of linear optics to implement a computational power beyond the one of a classical computer. Such ""hard-to-simulate"" scenario is disclosed when multiphoton-multimode platforms are realized. The 3D-QUEST research program will focus on three tasks of growing difficulty.
A-1. To simulate bosonic-fermionic dynamics with integrated optical systems acting on 2 photon entangled states.
A-2. To pave the way towards hard-to-simulate, scalable quantum linear optical circuits by investigating m-port interferometers acting on n-photon states with n>2.
A-3. To exploit 3-dimensional integrated structures for the observation of new quantum optical phenomena and for the quantum simulation of more complex scenarios.
3D-QUEST will exploit the potential of the femtosecond laser writing integrated waveguides. This technique will be adopted to realize 3-dimensional capabilities and high flexibility, bringing in this way the optical quantum simulation in to new regime."
Summary
"Quantum information was born from the merging of classical information and quantum physics. Its main objective consists of understanding the quantum nature of information and learning how to process it by using physical systems which operate by following quantum mechanics laws. Quantum simulation is a fundamental instrument to investigate phenomena of quantum systems dynamics, such as quantum transport, particle localizations and energy transfer, quantum-to-classical transition, and even quantum improved computation, all tasks that are hard to simulate with classical approaches. Within this framework integrated photonic circuits have a strong potential to realize quantum information processing by optical systems.
The aim of 3D-QUEST is to develop and implement quantum simulation by exploiting 3-dimensional integrated photonic circuits. 3D-QUEST is structured to demonstrate the potential of linear optics to implement a computational power beyond the one of a classical computer. Such ""hard-to-simulate"" scenario is disclosed when multiphoton-multimode platforms are realized. The 3D-QUEST research program will focus on three tasks of growing difficulty.
A-1. To simulate bosonic-fermionic dynamics with integrated optical systems acting on 2 photon entangled states.
A-2. To pave the way towards hard-to-simulate, scalable quantum linear optical circuits by investigating m-port interferometers acting on n-photon states with n>2.
A-3. To exploit 3-dimensional integrated structures for the observation of new quantum optical phenomena and for the quantum simulation of more complex scenarios.
3D-QUEST will exploit the potential of the femtosecond laser writing integrated waveguides. This technique will be adopted to realize 3-dimensional capabilities and high flexibility, bringing in this way the optical quantum simulation in to new regime."
Max ERC Funding
1 474 800 €
Duration
Start date: 2012-08-01, End date: 2017-07-31
Project acronym 3DSPIN
Project 3-Dimensional Maps of the Spinning Nucleon
Researcher (PI) Alessandro Bacchetta
Host Institution (HI) UNIVERSITA DEGLI STUDI DI PAVIA
Call Details Consolidator Grant (CoG), PE2, ERC-2014-CoG
Summary How does the inside of the proton look like? What generates its spin?
3DSPIN will deliver essential information to answer these questions at the frontier of subnuclear physics.
At present, we have detailed maps of the distribution of quarks and gluons in the nucleon in 1D (as a function of their momentum in a single direction). We also know that quark spins account for only about 1/3 of the spin of the nucleon.
3DSPIN will lead the way into a new stage of nucleon mapping, explore the distribution of quarks in full 3D momentum space and obtain unprecedented information on orbital angular momentum.
Goals
1. extract from experimental data the 3D distribution of quarks (in momentum space), as described by Transverse-Momentum Distributions (TMDs);
2. obtain from TMDs information on quark Orbital Angular Momentum (OAM).
Methodology
3DSPIN will implement state-of-the-art fitting procedures to analyze relevant experimental data and extract quark TMDs, similarly to global fits of standard parton distribution functions. Information about quark angular momentum will be obtained through assumptions based on theoretical considerations. The next five years represent an ideal time window to accomplish our goals, thanks to the wealth of expected data from deep-inelastic scattering experiments (COMPASS, Jefferson Lab), hadronic colliders (Fermilab, BNL, LHC), and electron-positron colliders (BELLE, BABAR). The PI has a strong reputation in this field. The group will operate in partnership with the Italian National Institute of Nuclear Physics and in close interaction with leading experts and experimental collaborations worldwide.
Impact
Mapping the 3D structure of chemical compounds has revolutionized chemistry. Similarly, mapping the 3D structure of the nucleon will have a deep impact on our understanding of the fundamental constituents of matter. We will open new perspectives on the dynamics of quarks and gluons and sharpen our view of high-energy processes involving nucleons.
Summary
How does the inside of the proton look like? What generates its spin?
3DSPIN will deliver essential information to answer these questions at the frontier of subnuclear physics.
At present, we have detailed maps of the distribution of quarks and gluons in the nucleon in 1D (as a function of their momentum in a single direction). We also know that quark spins account for only about 1/3 of the spin of the nucleon.
3DSPIN will lead the way into a new stage of nucleon mapping, explore the distribution of quarks in full 3D momentum space and obtain unprecedented information on orbital angular momentum.
Goals
1. extract from experimental data the 3D distribution of quarks (in momentum space), as described by Transverse-Momentum Distributions (TMDs);
2. obtain from TMDs information on quark Orbital Angular Momentum (OAM).
Methodology
3DSPIN will implement state-of-the-art fitting procedures to analyze relevant experimental data and extract quark TMDs, similarly to global fits of standard parton distribution functions. Information about quark angular momentum will be obtained through assumptions based on theoretical considerations. The next five years represent an ideal time window to accomplish our goals, thanks to the wealth of expected data from deep-inelastic scattering experiments (COMPASS, Jefferson Lab), hadronic colliders (Fermilab, BNL, LHC), and electron-positron colliders (BELLE, BABAR). The PI has a strong reputation in this field. The group will operate in partnership with the Italian National Institute of Nuclear Physics and in close interaction with leading experts and experimental collaborations worldwide.
Impact
Mapping the 3D structure of chemical compounds has revolutionized chemistry. Similarly, mapping the 3D structure of the nucleon will have a deep impact on our understanding of the fundamental constituents of matter. We will open new perspectives on the dynamics of quarks and gluons and sharpen our view of high-energy processes involving nucleons.
Max ERC Funding
1 509 000 €
Duration
Start date: 2015-07-01, End date: 2020-12-31
Project acronym 3FLEX
Project Three-Component Fermi Gas Lattice Experiment
Researcher (PI) Selim Jochim
Host Institution (HI) RUPRECHT-KARLS-UNIVERSITAET HEIDELBERG
Call Details Starting Grant (StG), PE2, ERC-2011-StG_20101014
Summary Understanding the many-body physics of strongly correlated systems has always been a major challenge for theoretical and experimental physics. The recent advances in the field of ultracold quantum gases have opened a completely new way to study such strongly correlated systems. It is now feasible to use ultracold gases as quantum simulators for such diverse systems such as the Hubbard model or the BCS-BEC crossover. The objective of this project is to study a three-component Fermi gas in an optical lattice, a system with rich many-body physics. With our experiments we aim to contribute to the understanding of exotic phases which are discussed in the context of QCD and condensed matter physics.
Summary
Understanding the many-body physics of strongly correlated systems has always been a major challenge for theoretical and experimental physics. The recent advances in the field of ultracold quantum gases have opened a completely new way to study such strongly correlated systems. It is now feasible to use ultracold gases as quantum simulators for such diverse systems such as the Hubbard model or the BCS-BEC crossover. The objective of this project is to study a three-component Fermi gas in an optical lattice, a system with rich many-body physics. With our experiments we aim to contribute to the understanding of exotic phases which are discussed in the context of QCD and condensed matter physics.
Max ERC Funding
1 469 040 €
Duration
Start date: 2011-08-01, End date: 2016-07-31
Project acronym 4D IMAGING
Project Towards 4D Imaging of Fundamental Processes on the Atomic and Sub-Atomic Scale
Researcher (PI) Ferenc Krausz
Host Institution (HI) LUDWIG-MAXIMILIANS-UNIVERSITAET MUENCHEN
Call Details Advanced Grant (AdG), PE2, ERC-2009-AdG
Summary State-of-the-art microscopy and diffraction imaging provides insight into the atomic and sub-atomic structure of matter. They permit determination of the positions of atoms in a crystal lattice or in a molecule as well as the distribution of electrons inside atoms. State-of-the-art time-resolved spectroscopy with femtosecond and attosecond resolution provides access to dynamic changes in the atomic and electronic structure of matter. Our proposal aims at combining these two frontier techniques of XXI century science to make a long-standing dream of scientist come true: the direct observation of atoms and electrons in their natural state: in motion. Shifts in the atoms positions by tens to hundreds of picometers can make chemical bonds break apart or newly form, changing the structure and/or chemical composition of matter. Electronic motion on similar scales may result in the emission of light, or the initiation of processes that lead to a change in physical or chemical properties, or biological function. These motions happen within femtoseconds and attoseconds, respectively. To make them observable, we need a 4-dimensional (4D) imaging technique capable of recording freeze-frame snapshots of microscopic systems with picometer spatial resolution and femtosecond to attosecond exposure time. The motion can then be visualized by slow-motion replay of the freeze-frame shots. The goal of this project is to develop a 4D imaging technique that will ultimately offer picometer resolution is space and attosecond resolution in time.
Summary
State-of-the-art microscopy and diffraction imaging provides insight into the atomic and sub-atomic structure of matter. They permit determination of the positions of atoms in a crystal lattice or in a molecule as well as the distribution of electrons inside atoms. State-of-the-art time-resolved spectroscopy with femtosecond and attosecond resolution provides access to dynamic changes in the atomic and electronic structure of matter. Our proposal aims at combining these two frontier techniques of XXI century science to make a long-standing dream of scientist come true: the direct observation of atoms and electrons in their natural state: in motion. Shifts in the atoms positions by tens to hundreds of picometers can make chemical bonds break apart or newly form, changing the structure and/or chemical composition of matter. Electronic motion on similar scales may result in the emission of light, or the initiation of processes that lead to a change in physical or chemical properties, or biological function. These motions happen within femtoseconds and attoseconds, respectively. To make them observable, we need a 4-dimensional (4D) imaging technique capable of recording freeze-frame snapshots of microscopic systems with picometer spatial resolution and femtosecond to attosecond exposure time. The motion can then be visualized by slow-motion replay of the freeze-frame shots. The goal of this project is to develop a 4D imaging technique that will ultimately offer picometer resolution is space and attosecond resolution in time.
Max ERC Funding
2 500 000 €
Duration
Start date: 2010-03-01, End date: 2015-02-28
Project acronym 4DPHOTON
Project Beyond Light Imaging: High-Rate Single-Photon Detection in Four Dimensions
Researcher (PI) Massimiliano FIORINI
Host Institution (HI) ISTITUTO NAZIONALE DI FISICA NUCLEARE
Call Details Consolidator Grant (CoG), PE2, ERC-2018-COG
Summary Goal of the 4DPHOTON project is the development and construction of a photon imaging detector with unprecedented performance. The proposed device will be capable of detecting fluxes of single-photons up to one billion photons per second, over areas of several square centimetres, and will measure - for each photon - position and time simultaneously with resolutions better than ten microns and few tens of picoseconds, respectively. These figures of merit will open many important applications allowing significant advances in particle physics, life sciences or other emerging fields where excellent timing and position resolutions are simultaneously required.
Our goal will be achieved thanks to the use of an application-specific integrated circuit in 65 nm complementary metal-oxide-semiconductor (CMOS) technology, that will deliver a timing resolution of few tens of picoseconds at the pixel level, over few hundred thousand individually-active pixel channels, allowing very high rates of photons to be detected, and the corresponding information digitized and transferred to a processing unit.
As a result of the 4DPHOTON project we will remove the constraints that many light imaging applications have due to the lack of precise single-photon information on four dimensions (4D): the three spatial coordinates and time simultaneously. In particular, we will prove the performance of this detector in the field of particle physics, performing the reconstruction of Cherenkov photon rings with a timing resolution of ten picoseconds. With its excellent granularity, timing resolution, rate capability and compactness, this detector will represent a new paradigm for the realisation of future Ring Imaging Cherenkov detectors, capable of achieving high efficiency particle identification in environments with very high particle multiplicities, exploiting time-association of the photon hits.
Summary
Goal of the 4DPHOTON project is the development and construction of a photon imaging detector with unprecedented performance. The proposed device will be capable of detecting fluxes of single-photons up to one billion photons per second, over areas of several square centimetres, and will measure - for each photon - position and time simultaneously with resolutions better than ten microns and few tens of picoseconds, respectively. These figures of merit will open many important applications allowing significant advances in particle physics, life sciences or other emerging fields where excellent timing and position resolutions are simultaneously required.
Our goal will be achieved thanks to the use of an application-specific integrated circuit in 65 nm complementary metal-oxide-semiconductor (CMOS) technology, that will deliver a timing resolution of few tens of picoseconds at the pixel level, over few hundred thousand individually-active pixel channels, allowing very high rates of photons to be detected, and the corresponding information digitized and transferred to a processing unit.
As a result of the 4DPHOTON project we will remove the constraints that many light imaging applications have due to the lack of precise single-photon information on four dimensions (4D): the three spatial coordinates and time simultaneously. In particular, we will prove the performance of this detector in the field of particle physics, performing the reconstruction of Cherenkov photon rings with a timing resolution of ten picoseconds. With its excellent granularity, timing resolution, rate capability and compactness, this detector will represent a new paradigm for the realisation of future Ring Imaging Cherenkov detectors, capable of achieving high efficiency particle identification in environments with very high particle multiplicities, exploiting time-association of the photon hits.
Max ERC Funding
1 975 000 €
Duration
Start date: 2019-12-01, End date: 2024-11-30
Project acronym 4TH-NU-AVENUE
Project Search for a fourth neutrino with a PBq anti-neutrino source
Researcher (PI) Thierry Michel René Lasserre
Host Institution (HI) COMMISSARIAT A L ENERGIE ATOMIQUE ET AUX ENERGIES ALTERNATIVES
Call Details Starting Grant (StG), PE2, ERC-2012-StG_20111012
Summary Several observed anomalies in neutrino oscillation data can be explained by a hypothetical fourth neutrino separated from the three standard neutrinos by a squared mass difference of a few eV2. This hypothesis can be tested with a PBq (ten kilocurie scale) 144Ce antineutrino beta-source deployed at the center of a large low background liquid scintillator detector, such like Borexino, KamLAND, and SNO+. In particular, the compact size of such a source could yield an energy-dependent oscillating pattern in event spatial distribution that would unambiguously determine neutrino mass differences and mixing angles.
The proposed program aims to perform the necessary research and developments to produce and deploy an intense antineutrino source in a large liquid scintillator detector. Our program will address the definition of the production process of the neutrino source as well as its experimental characterization, the detailed physics simulation of both signal and backgrounds, the complete design and the realization of the thick shielding, the preparation of the interfaces with the antineutrino detector, including the safety and security aspects.
Summary
Several observed anomalies in neutrino oscillation data can be explained by a hypothetical fourth neutrino separated from the three standard neutrinos by a squared mass difference of a few eV2. This hypothesis can be tested with a PBq (ten kilocurie scale) 144Ce antineutrino beta-source deployed at the center of a large low background liquid scintillator detector, such like Borexino, KamLAND, and SNO+. In particular, the compact size of such a source could yield an energy-dependent oscillating pattern in event spatial distribution that would unambiguously determine neutrino mass differences and mixing angles.
The proposed program aims to perform the necessary research and developments to produce and deploy an intense antineutrino source in a large liquid scintillator detector. Our program will address the definition of the production process of the neutrino source as well as its experimental characterization, the detailed physics simulation of both signal and backgrounds, the complete design and the realization of the thick shielding, the preparation of the interfaces with the antineutrino detector, including the safety and security aspects.
Max ERC Funding
1 500 000 €
Duration
Start date: 2012-10-01, End date: 2018-09-30
Project acronym 5HT-OPTOGENETICS
Project Optogenetic Analysis of Serotonin Function in the Mammalian Brain
Researcher (PI) Zachary Mainen
Host Institution (HI) FUNDACAO D. ANNA SOMMER CHAMPALIMAUD E DR. CARLOS MONTEZ CHAMPALIMAUD
Call Details Advanced Grant (AdG), LS5, ERC-2009-AdG
Summary Serotonin (5-HT) is implicated in a wide spectrum of brain functions and disorders. However, its functions remain controversial and enigmatic. We suggest that past work on the 5-HT system have been significantly hampered by technical limitations in the selectivity and temporal resolution of the conventional pharmacological and electrophysiological methods that have been applied. We therefore propose to apply novel optogenetic methods that will allow us to overcome these limitations and thereby gain new insight into the biological functions of this important molecule. In preliminary studies, we have demonstrated that we can deliver exogenous proteins specifically to 5-HT neurons using viral vectors. Our objectives are to (1) record, (2) stimulate and (3) silence the activity of 5-HT neurons with high molecular selectivity and temporal precision by using genetically-encoded sensors, activators and inhibitors of neural function. These tools will allow us to monitor and control the 5-HT system in real-time in freely-behaving animals and thereby to establish causal links between information processing in 5-HT neurons and specific behaviors. In combination with quantitative behavioral assays, we will use this approach to define the role of 5-HT in sensory, motor and cognitive functions. The significance of the work is three-fold. First, we will establish a new arsenal of tools for probing the physiological and behavioral functions of 5-HT neurons. Second, we will make definitive tests of major hypotheses of 5-HT function. Third, we will have possible therapeutic applications. In this way, the proposed work has the potential for a major impact in research on the role of 5-HT in brain function and dysfunction.
Summary
Serotonin (5-HT) is implicated in a wide spectrum of brain functions and disorders. However, its functions remain controversial and enigmatic. We suggest that past work on the 5-HT system have been significantly hampered by technical limitations in the selectivity and temporal resolution of the conventional pharmacological and electrophysiological methods that have been applied. We therefore propose to apply novel optogenetic methods that will allow us to overcome these limitations and thereby gain new insight into the biological functions of this important molecule. In preliminary studies, we have demonstrated that we can deliver exogenous proteins specifically to 5-HT neurons using viral vectors. Our objectives are to (1) record, (2) stimulate and (3) silence the activity of 5-HT neurons with high molecular selectivity and temporal precision by using genetically-encoded sensors, activators and inhibitors of neural function. These tools will allow us to monitor and control the 5-HT system in real-time in freely-behaving animals and thereby to establish causal links between information processing in 5-HT neurons and specific behaviors. In combination with quantitative behavioral assays, we will use this approach to define the role of 5-HT in sensory, motor and cognitive functions. The significance of the work is three-fold. First, we will establish a new arsenal of tools for probing the physiological and behavioral functions of 5-HT neurons. Second, we will make definitive tests of major hypotheses of 5-HT function. Third, we will have possible therapeutic applications. In this way, the proposed work has the potential for a major impact in research on the role of 5-HT in brain function and dysfunction.
Max ERC Funding
2 318 636 €
Duration
Start date: 2010-07-01, End date: 2015-12-31
Project acronym 5HTCircuits
Project Modulation of cortical circuits and predictive neural coding by serotonin
Researcher (PI) Zachary Mainen
Host Institution (HI) FUNDACAO D. ANNA SOMMER CHAMPALIMAUD E DR. CARLOS MONTEZ CHAMPALIMAUD
Call Details Advanced Grant (AdG), LS5, ERC-2014-ADG
Summary Serotonin (5-HT) is a central neuromodulator and a major target of therapeutic psychoactive drugs, but relatively little is known about how it modulates information processing in neural circuits. The theory of predictive coding postulates that the brain combines raw bottom-up sensory information with top-down information from internal models to make perceptual inferences about the world. We hypothesize, based on preliminary data and prior literature, that a role of 5-HT in this process is to report prediction errors and promote the suppression and weakening of erroneous internal models. We propose that it does this by inhibiting top-down relative to bottom-up cortical information flow. To test this hypothesis, we propose a set of experiments in mice performing olfactory perceptual tasks. Our specific aims are: (1) We will test whether 5-HT neurons encode sensory prediction errors. (2) We will test their causal role in using predictive cues to guide perceptual decisions. (3) We will characterize how 5-HT influences the encoding of sensory information by neuronal populations in the olfactory cortex and identify the underlying circuitry. (4) Finally, we will map the effects of 5-HT across the whole brain and use this information to target further causal manipulations to specific 5-HT projections. We accomplish these aims using state-of-the-art optogenetic, electrophysiological and imaging techniques (including 9.4T small-animal functional magnetic resonance imaging) as well as psychophysical tasks amenable to quantitative analysis and computational theory. Together, these experiments will tackle multiple facets of an important general computational question, bringing to bear an array of cutting-edge technologies to address with unprecedented mechanistic detail how 5-HT impacts neural coding and perceptual decision-making.
Summary
Serotonin (5-HT) is a central neuromodulator and a major target of therapeutic psychoactive drugs, but relatively little is known about how it modulates information processing in neural circuits. The theory of predictive coding postulates that the brain combines raw bottom-up sensory information with top-down information from internal models to make perceptual inferences about the world. We hypothesize, based on preliminary data and prior literature, that a role of 5-HT in this process is to report prediction errors and promote the suppression and weakening of erroneous internal models. We propose that it does this by inhibiting top-down relative to bottom-up cortical information flow. To test this hypothesis, we propose a set of experiments in mice performing olfactory perceptual tasks. Our specific aims are: (1) We will test whether 5-HT neurons encode sensory prediction errors. (2) We will test their causal role in using predictive cues to guide perceptual decisions. (3) We will characterize how 5-HT influences the encoding of sensory information by neuronal populations in the olfactory cortex and identify the underlying circuitry. (4) Finally, we will map the effects of 5-HT across the whole brain and use this information to target further causal manipulations to specific 5-HT projections. We accomplish these aims using state-of-the-art optogenetic, electrophysiological and imaging techniques (including 9.4T small-animal functional magnetic resonance imaging) as well as psychophysical tasks amenable to quantitative analysis and computational theory. Together, these experiments will tackle multiple facets of an important general computational question, bringing to bear an array of cutting-edge technologies to address with unprecedented mechanistic detail how 5-HT impacts neural coding and perceptual decision-making.
Max ERC Funding
2 486 074 €
Duration
Start date: 2016-01-01, End date: 2020-12-31