Dopamine release in human associative striatum during reversal learning

Nature Communications, Год журнала: 2024, Номер 15(1)

Опубликована: Янв. 2, 2024

Abstract The dopaminergic system is firmly implicated in reversal learning but human measurements of dopamine release as a correlate success are lacking. Dopamine and hemodynamic brain activity response to unexpected changes action-outcome probabilities here explored using simultaneous dynamic [11C]Raclopride PET-fMRI computational modelling behavior. When participants encounter reversed reward during card guessing game, observed associative striatum. Individual differences absolute prediction error sensitivity errors associated with peak receptor occupancy. fMRI perseverance at the onset spatially overlap site release. Trial-by-trial correlates show striatum association cortices, closely overlapping location release, separable from valence signal ventral results converge implicate striatal central component learning, possibly signifying need for increased cognitive control when new stimuli-responses should be learned.

Язык: Английский

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Establishing connectivity through microdissections of midbrain stimulation-related neural circuits

Brain, Год журнала: 2024, Номер 147(9), С. 3083 - 3098

Опубликована: Май 29, 2024

Abstract Comprehensive understanding of the neural circuits involving ventral tegmental area is essential for elucidating anatomofunctional mechanisms governing human behaviour, in addition to therapeutic and adverse effects deep brain stimulation neuropsychiatric diseases. Although has been targeted successfully with different diseases, axonal connectivity region not fully understood. Here, using fibre microdissections cadaveric hemispheres, population-based high-definition tractography previously reported hotspots, we find that participates an intricate network serotonergic pontine nuclei, basal ganglia, limbic system, forebrain prefrontal cortex, which implicated treatment obsessive–compulsive disorder, major depressive Alzheimer’s disease, cluster headaches aggressive behaviours.

Язык: Английский

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The Impact of Optical Undersampling on the Ca2+ Signal Resolution in Ca2+ Imaging of Spontaneous Neuronal Activity

Journal of Integrative Neuroscience, Год журнала: 2025, Номер 24(1)

Опубликована: Янв. 21, 2025

Background: In neuroscience, Ca2+ imaging is a prevalent technique used to infer neuronal electrical activity, often relying on optical signals recorded at low sampling rates (3 30 Hz) across multiple neurons simultaneously. This study investigated whether increasing the rate preserves critical information that may be missed slower acquisition speeds. Methods: Primary cultures were prepared from cortex of newborn pups. Neurons loaded with Oregon Green BAPTA-1 AM (OGB1-AM) fluorescent indicator. Spontaneous activity was (14 and high (500 rates, same (n = 269) analyzed under both conditions. We compared signal amplitude, duration, frequency. Results: Although recurring transients appeared visually similar 14 Hz 500 Hz, quantitative analysis revealed significantly faster rise times shorter durations (half-widths) higher rate. Small-amplitude transients, undetectable became evident particularly in neuropil (putative dendrites axons), but not nearby cell bodies. Large exhibited greater amplitudes temporal dynamics somas, potentially due surface-to-volume ratio dendrites. bulk-loaded OGB1-AM, nucleus-mediated distortions observed every neuron examined 57). Specifically, two regions interest (ROIs) different segments body displayed dye accumulation nucleus. Conclusions: Our findings reveal undersampling leads three types loss: (1) distortion for large-amplitude (2) failure detect small-amplitude bodies, (3) omission neuropil.

Язык: Английский

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Opponent learning with different representations in the cortico-basal ganglia pathways can develop obsession-compulsion cycle

PLoS Computational Biology, Год журнала: 2023, Номер 19(6), С. e1011206 - e1011206

Опубликована: Июнь 15, 2023

Obsessive-compulsive disorder (OCD) has been suggested to be associated with impairment of model-based behavioral control. Meanwhile, recent work shorter memory trace for negative than positive prediction errors (PEs) in OCD. We explored relations between these two suggestions through computational modeling. Based on the properties cortico-basal ganglia pathways, we modeled human as an agent having a combination successor representation (SR)-based system that enables model-based-like control and individual (IR)-based only hosts model-free control, systems potentially learning from PEs different rates. simulated agent's behavior environmental model used describes potential development obsession-compulsion cycle. found dual-system could develop enhanced cycle, similarly imbalance work, if SR- IR-based learned mainly PEs, respectively. then such opponent SR+IR two-stage decision task, comparison SR-based Fitting agents' by weighing developed original task study resulted smaller weights SR-only agent. These results reconcile previous about OCD, i.e., impaired imbalance, raising novel possibility model(SR)-based controllers underlies obsession-compulsion. Our cannot explain OCD patients punishment, rather reward, contexts, but it resolved operates also recently revealed non-canonical ganglia-dopamine circuit threat/aversiveness, reinforcement learning, aversive SR + appetitive IR actually environment is differently.

Язык: Английский

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Reward perseveration is shaped by GABAA-mediated dopamine pauses

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Май 9, 2024

When animals unexpectedly fail, their dopamine neurons undergo phasic inhibition that canonically drives extinction learning-a cognitive-flexibility mechanism for discarding outdated strategies. However, the existing evidence equates natural and artificial inhibition, despite spatiotemporal differences. Addressing this gap, we targeted a GABA

Язык: Английский

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Extinction burst could be explained by curiosity-driven reinforcement learning

bioRxiv (Cold Spring Harbor Laboratory), Год журнала: 2024, Номер unknown

Опубликована: Авг. 29, 2024

Curiosity encourages agents to explore their environment, leading learning opportunities. Although psychology and neurobiology have tackled how external rewards control behavior, intrinsic factors behavior remains unclear. An extinction burst is a behavioral phenomenon in which sudden increase the frequency of immediately follows omission reward. textbook knowledge psychology, there little empirical evidence it experimental situations. In this study, we show that can be explained by curiosity combining computational modeling demonstrations mice. First, built reinforcement model incorporating curiosity, defined as expected reward prediction errors, additively controlled agent's primary Simulations revealed curiosity-driven produced an intensity depended on probability. Second, established procedure captured bursts setup using We conducted operant conditioning task with head-fixed mice, followed after pressing lever at given After training sessions, occasionally withheld delivery when mice performed task. found phasic responses occurred were rewarded high probability, suggesting magnitude errors burst. These results provide theoretical adapting ever-changing environment.

Язык: Английский

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Frustrative Nonreward: Behavior, Circuits, Neurochemistry, and Disorders

Journal of Neuroscience, Год журнала: 2024, Номер 44(40), С. e1021242024 - e1021242024

Опубликована: Окт. 2, 2024

The surprising omission or reduction of vital resources (food, fluid, social partners) can induce an aversive emotion known as frustrative nonreward (FNR), which influence subsequent behavior and physiology. FNR is integral mediator irritability/aggression, motivation (substance use disorders, depression), anxiety/fear/threat, learning/conditioning, behavior. Despite substantial progress in the study during twentieth century, research lagged later part century into early twenty-first until National Institute Mental Health's Research Domain Criteria initiative included loss components negative valence domain. This led to a renaissance new paradigms relevant basic clinical science alike. COVID-19 pandemic's extensive individual restrictions were correlated with increased drug alcohol use, conflict, irritability, suicide, all potential consequences FNR. article highlights animal models related these psychiatric disorders symptoms presents recent advances identifying brain regions neurotransmitters implicated.

Язык: Английский

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Prediction error in dopamine neurons during associative learning

Neuroscience Research, Год журнала: 2023, Номер 199, С. 12 - 20

Опубликована: Июль 13, 2023

Dopamine neurons have long been thought to facilitate learning by broadcasting reward prediction error (RPE), a teaching signal used in machine learning, but more recent work has advanced alternative models of dopamine's computational role. Here, I revisit this critical issue and review new experimental evidences that tighten the link between dopamine activity RPE. First, introduce observation gradual backward shift had eluded researchers for over decade. also discuss several other findings, such as ramping, were initially interpreted conflict later found be consistent with These findings improve our understanding neural computation neurons.

Язык: Английский

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Sensorimotor-linked reward modulates smooth pursuit eye movements in monkeys

Frontiers in Neuroscience, Год журнала: 2024, Номер 17

Опубликована: Янв. 9, 2024

Reward is essential for shaping behavior. Using sensory cues to imply forthcoming rewards, previous studies have demonstrated powerful effects of rewards on Nevertheless, the impact reward sensorimotor transformation, particularly when linked behavior remains uncertain. In this study, we investigated how modulates smooth pursuit eye movements in monkeys. Three distinct associations between and were conducted independent blocks. Results indicated that increased velocity during steady-state pursuit, rather than initiation. The influence depended particular association reward: a faster was with reward. Neither rewarding slower nor randomizing had significant effect findings support existence mechanisms involved initiation phases contribute deeper understanding interacts these two periods pursuit.

Язык: Английский

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Interactions between memory and reward systems

Elsevier eBooks, Год журнала: 2024, Номер unknown

Опубликована: Янв. 1, 2024

Язык: Английский

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