Project acronym Human Decisions
Project The Neural Determinants of Perceptual Decision Making in the Human Brain
Researcher (PI) Redmond O'connell
Host Institution (HI) THE PROVOST, FELLOWS, FOUNDATION SCHOLARS & THE OTHER MEMBERS OF BOARD OF THE COLLEGE OF THE HOLY & UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN
Call Details Starting Grant (StG), LS5, ERC-2014-STG
Summary How do we make reliable decisions given sensory information that is often weak or ambiguous? Current theories center on a brain mechanism whereby sensory evidence is integrated over time into a “decision variable” which triggers the appropriate action upon reaching a criterion. Neural signals fitting this role have been identified in monkey electrophysiology but efforts to study the neural dynamics underpinning human decision making have been hampered by technical challenges associated with non-invasive recording. This proposal builds on a recent paradigm breakthrough made by the applicant that enables parallel tracking of discrete neural signals that can be unambiguously linked to the three key information processing stages necessary for simple perceptual decisions: sensory encoding, decision formation and motor preparation. Chief among these is a freely-evolving decision variable signal which builds at an evidence-dependent rate up to an action-triggering threshold and precisely determines the timing and accuracy of perceptual reports at the single-trial level. This provides an unprecedented neurophysiological window onto the distinct parameters of the human decision process such that the underlying mechanisms of several major behavioral phenomena can finally be investigated. This proposal seeks to develop a systems-level understanding of perceptual decision making in the human brain by tackling three core questions: 1) what are the neural adaptations that allow us to deal with speed pressure and variations in the reliability of the physically presented evidence? 2) What neural mechanism determines our subjective confidence in a decision? and 3) How does aging impact on the distinct neural components underpinning perceptual decision making? Each of the experiments described in this proposal will definitively test key predictions from prominent theoretical models using a combination of temporally precise neurophysiological measurement and psychophysical modelling.
Summary
How do we make reliable decisions given sensory information that is often weak or ambiguous? Current theories center on a brain mechanism whereby sensory evidence is integrated over time into a “decision variable” which triggers the appropriate action upon reaching a criterion. Neural signals fitting this role have been identified in monkey electrophysiology but efforts to study the neural dynamics underpinning human decision making have been hampered by technical challenges associated with non-invasive recording. This proposal builds on a recent paradigm breakthrough made by the applicant that enables parallel tracking of discrete neural signals that can be unambiguously linked to the three key information processing stages necessary for simple perceptual decisions: sensory encoding, decision formation and motor preparation. Chief among these is a freely-evolving decision variable signal which builds at an evidence-dependent rate up to an action-triggering threshold and precisely determines the timing and accuracy of perceptual reports at the single-trial level. This provides an unprecedented neurophysiological window onto the distinct parameters of the human decision process such that the underlying mechanisms of several major behavioral phenomena can finally be investigated. This proposal seeks to develop a systems-level understanding of perceptual decision making in the human brain by tackling three core questions: 1) what are the neural adaptations that allow us to deal with speed pressure and variations in the reliability of the physically presented evidence? 2) What neural mechanism determines our subjective confidence in a decision? and 3) How does aging impact on the distinct neural components underpinning perceptual decision making? Each of the experiments described in this proposal will definitively test key predictions from prominent theoretical models using a combination of temporally precise neurophysiological measurement and psychophysical modelling.
Max ERC Funding
1 382 643 €
Duration
Start date: 2015-05-01, End date: 2020-04-30
Project acronym MEME
Project Memory Engram Maintenance and Expression
Researcher (PI) Tomas RYAN
Host Institution (HI) THE PROVOST, FELLOWS, FOUNDATION SCHOLARS & THE OTHER MEMBERS OF BOARD OF THE COLLEGE OF THE HOLY & UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN
Call Details Starting Grant (StG), LS5, ERC-2016-STG
Summary The goal of this project is to understand how specific memory engrams are physically stored in the brain. Connectionist theories of memory storage have guided research into the neuroscience of memory for over a half century, but have received little direct proof due to experimental limitations. The major confound that has limited direct testing of such theories has been an inability to identify the cells and circuits that store specific memories. Memory engram technology, which allows the tagging and in vivo manipulation of specific engram cells, has recently allowed us to overcome this empirical limitation and has revolutionised the way memory can be studied in rodent models. Based on our research it is now known that sparse populations of hippocampal neurons that were active during a defined learning experience are both sufficient and necessary for retrieval of specific contextual memories. More recently we have established that hippocampal engram cells preferentially synapse directly onto postsynaptic engram cells. This “engram cell connectivity” could provide the neurobiological substrate for the storage of multimodal memories through a distributed engram circuit. However it is currently unknown whether engram cell connectivity itself is important for memory function. The proposed integrative neuroscience project will employ inter-disciplinary methods to directly probe the importance of engram cell connectivity for memory retrieval, storage, and encoding. The outcomes will directly inform a novel and comprehensive neurobiological model of memory engram storage.
Summary
The goal of this project is to understand how specific memory engrams are physically stored in the brain. Connectionist theories of memory storage have guided research into the neuroscience of memory for over a half century, but have received little direct proof due to experimental limitations. The major confound that has limited direct testing of such theories has been an inability to identify the cells and circuits that store specific memories. Memory engram technology, which allows the tagging and in vivo manipulation of specific engram cells, has recently allowed us to overcome this empirical limitation and has revolutionised the way memory can be studied in rodent models. Based on our research it is now known that sparse populations of hippocampal neurons that were active during a defined learning experience are both sufficient and necessary for retrieval of specific contextual memories. More recently we have established that hippocampal engram cells preferentially synapse directly onto postsynaptic engram cells. This “engram cell connectivity” could provide the neurobiological substrate for the storage of multimodal memories through a distributed engram circuit. However it is currently unknown whether engram cell connectivity itself is important for memory function. The proposed integrative neuroscience project will employ inter-disciplinary methods to directly probe the importance of engram cell connectivity for memory retrieval, storage, and encoding. The outcomes will directly inform a novel and comprehensive neurobiological model of memory engram storage.
Max ERC Funding
1 500 000 €
Duration
Start date: 2017-02-01, End date: 2022-01-31
Project acronym ODYSSEY
Project Open dynamics of interacting and disordered quantum systems
Researcher (PI) John GOOLD
Host Institution (HI) THE PROVOST, FELLOWS, FOUNDATION SCHOLARS & THE OTHER MEMBERS OF BOARD OF THE COLLEGE OF THE HOLY & UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN
Call Details Starting Grant (StG), PE3, ERC-2017-STG
Summary This research proposal focuses on the open quantum system dynamics of disordered and interacting many- body systems coupled to external baths. The dynamics of systems which contain both disorder and interactions are currently under intense theoretical investigation in condensed matter physics due to the discovery of a new phase of matter known as many-body localization. With the experimental realization of such systems in mind, this proposal addresses an essential issue which is to understand how coupling to external degrees of freedom influences dynamics. These systems are intrinsically complex and lie beyond the unitary closed system paradigm, so the research proposed here contains interdisciplinary methodology beyond the mainstream in condensed matter physics ranging from quantum information to quantum optics. The project has three principal objectives each of which would represent a major contribution to the field:
O1. To describe the dynamics of a interacting, disordered many-body systems when coupled to external baths.
O2. To perform a full characterization of spin and energy transport in their non-equilibrium steady state.
O3. To explore the system capabilities as steady state thermal machine from a systematic microscopic perspective.
This will be the first comprehensive study of the open system phenomenology of disordered interacting many-body
systems. It will also allow for the systematic study of energy and spin transport and the exploration of the potential of these systems as steady state thermal machines. In order to successfully carry out the work proposed here, the applicant will build a world class team at Trinity College Dublin. Due to his track record and interdisciplinary background in many-body physics, quantum information and statistical mechanics combined with his personal drive and ambition the applicant is in a formidable position to successfully undertake this task with the platform provided by this ERC Starting Grant.
Summary
This research proposal focuses on the open quantum system dynamics of disordered and interacting many- body systems coupled to external baths. The dynamics of systems which contain both disorder and interactions are currently under intense theoretical investigation in condensed matter physics due to the discovery of a new phase of matter known as many-body localization. With the experimental realization of such systems in mind, this proposal addresses an essential issue which is to understand how coupling to external degrees of freedom influences dynamics. These systems are intrinsically complex and lie beyond the unitary closed system paradigm, so the research proposed here contains interdisciplinary methodology beyond the mainstream in condensed matter physics ranging from quantum information to quantum optics. The project has three principal objectives each of which would represent a major contribution to the field:
O1. To describe the dynamics of a interacting, disordered many-body systems when coupled to external baths.
O2. To perform a full characterization of spin and energy transport in their non-equilibrium steady state.
O3. To explore the system capabilities as steady state thermal machine from a systematic microscopic perspective.
This will be the first comprehensive study of the open system phenomenology of disordered interacting many-body
systems. It will also allow for the systematic study of energy and spin transport and the exploration of the potential of these systems as steady state thermal machines. In order to successfully carry out the work proposed here, the applicant will build a world class team at Trinity College Dublin. Due to his track record and interdisciplinary background in many-body physics, quantum information and statistical mechanics combined with his personal drive and ambition the applicant is in a formidable position to successfully undertake this task with the platform provided by this ERC Starting Grant.
Max ERC Funding
1 333 325 €
Duration
Start date: 2018-07-01, End date: 2023-06-30
Project acronym QUEST
Project Quantitative electron and spin transport theory for organic crystals based devices
Researcher (PI) Stefano Sanvito
Host Institution (HI) THE PROVOST, FELLOWS, FOUNDATION SCHOLARS & THE OTHER MEMBERS OF BOARD OF THE COLLEGE OF THE HOLY & UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN
Call Details Starting Grant (StG), PE3, ERC-2012-StG_20111012
Summary Predicting the electron and spin transport properties of organic crystals is a formidable theoretical challenge as these are determined both by the electronic structure of the individual molecules and by the morphology of the crystal. Quest's research program seeks at developing a fully quantitative theory for electron and spin transport in organic crystals, which does not rely on external parameters and can be applied to materials underpinning a multitude of applications, ranging from organic electronics, to spintronics, to energy. In particular we aim at combining state of the art density functional theory with advanced quantum transport methods and Monte Carlo simulations. We will then construct a hierarchical computational protocol enabling us to evaluate electron and spin transport across different length scales at finite temperature, including effects originating from external fields (electric and magnetic). Our developed tools will form a software package to be distributed freely to academia.
Summary
Predicting the electron and spin transport properties of organic crystals is a formidable theoretical challenge as these are determined both by the electronic structure of the individual molecules and by the morphology of the crystal. Quest's research program seeks at developing a fully quantitative theory for electron and spin transport in organic crystals, which does not rely on external parameters and can be applied to materials underpinning a multitude of applications, ranging from organic electronics, to spintronics, to energy. In particular we aim at combining state of the art density functional theory with advanced quantum transport methods and Monte Carlo simulations. We will then construct a hierarchical computational protocol enabling us to evaluate electron and spin transport across different length scales at finite temperature, including effects originating from external fields (electric and magnetic). Our developed tools will form a software package to be distributed freely to academia.
Max ERC Funding
1 492 728 €
Duration
Start date: 2012-12-01, End date: 2018-11-30
Project acronym RLPHARMFMRI
Project Beyond dopamine: Characterizing the computational functions of midbrain modulatory neurotransmitter systems in human reinforcement learning using model-based pharmacological fMRI
Researcher (PI) John O'doherty
Host Institution (HI) THE PROVOST, FELLOWS, FOUNDATION SCHOLARS & THE OTHER MEMBERS OF BOARD OF THE COLLEGE OF THE HOLY & UNDIVIDED TRINITY OF QUEEN ELIZABETH NEAR DUBLIN
Call Details Starting Grant (StG), LS5, ERC-2009-StG
Summary Understanding how humans and other animals are able to learn from experience and use this information to select future behavioural strategies to obtain the reinforcers necessary for survival, is a fundamental research question in biology. Considerable progress has been made in recent years on the neural computational underpinnings of this process following the observation that the phasic activity of dopamine neurons in the midbrain resembles a prediction error from a formal computational theory known as reinforcement learning (RL). While much is known about the functions of dopamine in RL, much less is known about the computational functions of other modulatory neurotransmitter systems in the midbrain such as the cholinergic, norcpinephrine, and serotonergic systems. The goal of this research proposal to the ERC, is to begin a systematic study of the computational functions of these other neurotransmitter systems (beyond dopamine) in RL. To do this we will combine functional magnetic resonance imaging in human subjects while they perform simple decision making tasks and undergo pharmacological manipulations to modulate systemic levels of these different neurotransmitter systems. We will combine computational model-based analyses with fMRI and behavioural data in order to explore the effects that these pharmacological modulations exert on different parameters and modules within RL. Specifically, we will test the contributions that the cholinergic system makes in setting the learning rate during RL and in mediating computations of expected uncertainty in the distribution of rewards available, we will test for the role of norepinephrine in balancing the rate of exploration and exploitation during decision making, as well as in encoding the level of unexpected uncertainty, and we will explore the possible role of serotonin in setting the rate of temporal discounting for reward, or in encoding prediction errors during aversive as opposed to reward-learning.
Summary
Understanding how humans and other animals are able to learn from experience and use this information to select future behavioural strategies to obtain the reinforcers necessary for survival, is a fundamental research question in biology. Considerable progress has been made in recent years on the neural computational underpinnings of this process following the observation that the phasic activity of dopamine neurons in the midbrain resembles a prediction error from a formal computational theory known as reinforcement learning (RL). While much is known about the functions of dopamine in RL, much less is known about the computational functions of other modulatory neurotransmitter systems in the midbrain such as the cholinergic, norcpinephrine, and serotonergic systems. The goal of this research proposal to the ERC, is to begin a systematic study of the computational functions of these other neurotransmitter systems (beyond dopamine) in RL. To do this we will combine functional magnetic resonance imaging in human subjects while they perform simple decision making tasks and undergo pharmacological manipulations to modulate systemic levels of these different neurotransmitter systems. We will combine computational model-based analyses with fMRI and behavioural data in order to explore the effects that these pharmacological modulations exert on different parameters and modules within RL. Specifically, we will test the contributions that the cholinergic system makes in setting the learning rate during RL and in mediating computations of expected uncertainty in the distribution of rewards available, we will test for the role of norepinephrine in balancing the rate of exploration and exploitation during decision making, as well as in encoding the level of unexpected uncertainty, and we will explore the possible role of serotonin in setting the rate of temporal discounting for reward, or in encoding prediction errors during aversive as opposed to reward-learning.
Max ERC Funding
1 841 404 €
Duration
Start date: 2010-01-01, End date: 2010-09-30
