Biology subjects

Montague, R.

Publications and source records attributed to Montague, R..

6 recordsLinked to original sources

bioRxiv2026

Dynamics of dopamine transients in human olfactory epithelium during reward learning

Dopamine signaling is crucial for motivation, movement, and learning, but has remained beyond the reach of measurement in healthy humans. Here, we measured sub-second dopamine in the olfactory epithelium of healthy humans during two reward learning tasks with distinct reward types: liquid reward during a conditioning task and monetary reward during an economic exchange game. In both tasks, as trials progress, peak dopamine transients shift from rewarding outcomes back to reward-predictive cues. In the economic game, this pattern retrains quickly when reward magnitude or reward timing is changed without warning. These findings match the time transfer characteristics and amplitude dependence of temporal difference prediction error signals. The results also establish a new, minimally invasive route for recording fast dopamine signaling in healthy humans: the nose.

neuroscience↗

bioRxiv2026

Single neurons in the human substantia nigra encode social learning signals

Humans are remarkable at adapting to changing norms, yet we know little about how the human brain encodes these social signals at the single neuron level. Here, we recorded the activity of single neurons in the substantia nigra and globus pallidus in neurosurgical participants as they played an iterative ultimatum game versus human and computer avatars. Using computational modeling of behavior, we found that putative dopaminergic units in the substantia nigra tracked the valence of norm prediction errors, with greater encoding during gameplay with human versus computer avatars. Analogous analyses in the globus pallidus, a nucleus adjacent to the substantia nigra, found no significant effect. Our results identify a novel role for the substantia nigra in encoding social learning signals.

neuroscience↗

bioRxiv2026

Temporal-difference valence-partitioned Bayesian brains work out whether others are caring or uncaring

Working out whether others care for us is crucial in personal relationships and when seeking professional help. It is often most difficult for those most in need, e.g. following interpersonal traumata. Here, we introduce a simple Caring Attributions task and elucidate key computational mechanisms involved and, using EEG, the cortical activity representing the degree of belief that another is beneficent or maleficent. We find evidence for a new type of neurocomputational processing: valence-partitioned temporal-difference inference (TD-Bayes). This employs primary processing about latent causes, but also separate channels to represent these different valenced attributions, inspired by value-partitioned associative learning (VPAL). TD-Bayes uses slow propagation of beliefs using temporal-difference updating. These models gave a very good account of behaviour, slightly better than VPAL, but crucially, their partitioned representations have stronger, distinct representations in ERP signals. They provide a promising inroad into the understanding of how people may jump to atttibutions about caring vs. uncaring others.

neuroscience↗

bioRxiv2025

Synaptic vesicle glycoprotein 2 enables viable aneuploidy following centrosome amplification

Amplified centrosome number causes genomic instability, most severely through division into more than two aneuploid daughter cells (multipolar mitosis). Several mechanisms that suppress multipolar division have been uncovered, yet mechanisms that favor viable multipolar division are poorly understood. To uncover factors that promote viability in cells with frequent centrosome amplification and multipolar division, we conducted an unbiased Drosophila genetic screen. In 642 mutagenized lines, we exploited the ability of intestinal papillar cells to form and function despite multipolar divisions. Our top hit is an unnamed gene, CG3168. We name this gene synaptic vesicle glycoprotein 2, reflecting homology to human Synaptic Vesicle Glycoprotein 2 (SV2) proteins. GFP-tagged SV2 localizes to the plasma membrane. In cells with amplified centrosomes, SV2 positions membrane-adjacent centrosomes, which prevents severe errors in chromosome alignment and segregation. Our results uncover membrane-based multipolar division regulation and reveal a novel vulnerability in cells with common cancer properties.

cell biology↗

bioRxiv2023

Sub-second fluctuations in extracellular dopamine encode reward and punishment prediction errors in humans

In the mammalian brain, midbrain dopamine neuron activity is hypothesized to encode reward prediction errors that promote learning and guide behavior by causing rapid changes in dopamine levels in target brain regions. This hypothesis (and alternatives regarding dopamines role in punishment-learning) has limited direct evidence in humans. We report intracranial, sub-second measurements of dopamine release in human striatum measured while volunteers (i.e., patients undergoing deep brain stimulation (DBS) surgery) performed a probabilistic reward- and punishment-learning choice task designed to test whether dopamine release encodes only reward prediction errors or whether dopamine release may also encode adaptive punishment-learning signals. Results demonstrate that extracellular dopamine levels can encode both reward and punishment prediction errors, but may do so via by independent valence-specific pathways in the human brain. One-Sentence SummaryDopamine release encodes reward and punishment prediction errors via independent pathways in the human brain.

neuroscience↗

bioRxiv2021

Low amplitude burst detection of catecholamines

Machine learning advances in electrochemical detection have recently produced sub-second and concurrent detection of dopamine and serotonin during perception and action tasks in conscious humans. Here, we present a new machine learning approach to sub-second, concurrent separation of dopamine, norepinephrine, and serotonin. The method exploits a low amplitude burst protocol for the controlled voltage waveform and we demonstrate its efficacy by showing how it separates dopamine-induced signals from norepinephrine induced signals. Previous efforts to deploy electrochemical detection of dopamine in vivo have not separated the dopamine-dependent signal from a norepinephrine-dependent signal. Consequently, this new method can provide new insights into concurrent signaling by these two important neuromodulators.

neuroscience↗