近日，美国普林斯顿大学教授Carlos D. Brody及其课题组开发出知觉决策过程中动力机制和神经模式的转变。这一研究成果发表在2025年9月17日出版的国际学术期刊《自然》上。

在这里，该团队同时记录了数百个神经元，并结合了一种无监督的、基于深度学习的方法，以发现当动物积累脉动听觉证据时，大鼠额叶皮层和纹状体中与决策相关的神经动力学。该课题组发现轨迹沿着两个顺序的机制进化：一个由感官输入主导的初始阶段，随后是一个由自主动力主导的阶段，流动方向（即神经模式）与第一个机制在很大程度上是正交的。

研究小组认为，这种转变标志着做出决定的时刻，也就是动物下定决心的时刻。为了验证这一点，该课题组研究人员开发了一个简化的动力学模型来估计每次试验的假定神经推断承诺时间（nTc）。该模型捕获了不同的单神经元时间分布，如斜坡和阶梯。估计的nTc值不受刺激或反应时间的限制，而是在不同的试验中变化很大。如果nTc标志着承诺，在此之前的证据应该影响决定，而在此之后的证据则不应该影响决定。与nTc一致的行为分析证实了这一预测。他们的研究结果表明，决策承诺涉及动力机制和神经模式的快速、协调的转变，并表明nTc为研究大脑内部状态的快速变化提供了一个重要的神经标记。

据了解，知觉决策被认为是由具有吸引子动态的神经网络介导的。然而，决策过程中复杂的神经元反应背后的动力机制尚不清楚。

附：英文原文

Title: Transitions in dynamical regime and neural mode during perceptual decisions

Author: Luo, Thomas Zhihao, Kim, Timothy Doyeon, Gupta, Diksha, Bondy, Adrian G., Kopec, Charles D., Elliott, Verity A., DePasquale, Brian, Brody, Carlos D.

Issue&Volume: 2025-09-17

Abstract: Perceptual decision-making is thought to be mediated by neuronal networks with attractor dynamics1,2. However, the dynamics underlying the complex neuronal responses during decision-making remain unclear. Here we use simultaneous recordings of hundreds of neurons, combined with an unsupervised, deep-learning-based method, to discover decision-related neural dynamics in the rat frontal cortex and striatum as animals accumulate pulsatile auditory evidence. We found that trajectories evolved along two sequential regimes: an initial phase dominated by sensory inputs, followed by a phase dominated by autonomous dynamics, with the flow direction (that is, neural mode) largely orthogonal to that in the first regime. We propose that this transition marks the moment of decision commitment, that is, the time when the animal makes up its mind. To test this, we developed a simplified model of the dynamics to estimate a putative neurally inferred time of commitment (nTc) for each trial. This model captures diverse single-neuron temporal profiles, such as ramping and stepping3,4. The estimated nTc values were not time locked to stimulus or response timing but instead varied broadly across trials. If nTc marks commitment, evidence before this point should affect the decision, whereas evidence afterwards should not. Behavioural analysis aligned to nTc confirmed this prediction. Our findings show that decision commitment involves a rapid, coordinated transition in dynamical regime and neural mode and suggest that nTc offers a useful neural marker for studying rapid changes in internal brain state.

DOI: 10.1038/s41586-025-09528-4

Source: https://www.nature.com/articles/s41586-025-09528-4