Nguyen Quynh Nhu, Reinagel Pamela
Section of Neurobiology, Division of Biological Sciences, University of California, San Diego, San Diego, CA, United States.
Front Neurosci. 2022 Feb 22;16:794681. doi: 10.3389/fnins.2022.794681. eCollection 2022.
When observers make rapid, difficult perceptual decisions, their response time is highly variable from trial to trial. In a visual motion discrimination task, it has been reported that human accuracy declines with increasing response time, whereas rat accuracy increases with response time. This is of interest because different mathematical theories of decision-making differ in their predictions regarding the correlation of accuracy with response time. On the premise that perceptual decision-making mechanisms are likely to be conserved among mammals, we seek to unify the rodent and primate results in a common theoretical framework. We show that a bounded drift diffusion model (DDM) can explain both effects with variable parameters: trial-to-trial variability in the starting point of the diffusion process produces the pattern typically observed in rats, whereas variability in the drift rate produces the pattern typically observed in humans. We further show that the same effects can be produced by deterministic biases, even in the absence of parameter stochasticity or parameter change within a trial.
当观察者做出快速、困难的感知决策时，他们的反应时间在每次试验中都有很大的变化。在一项视觉运动辨别任务中，据报道人类的准确率会随着反应时间的增加而下降，而大鼠的准确率则随着反应时间的增加而提高。这很有意思，因为不同的决策数学理论在关于准确率与反应时间相关性的预测上存在差异。基于感知决策机制可能在哺乳动物中具有保守性这一前提，我们试图在一个共同的理论框架中统一啮齿动物和灵长类动物的研究结果。我们表明，一个有界漂移扩散模型（DDM）可以用可变参数解释这两种效应：扩散过程起点的逐次试验变异性产生了通常在大鼠中观察到的模式，而漂移率的变异性产生了通常在人类中观察到的模式。我们进一步表明，即使在试验中没有参数随机性或参数变化的情况下，确定性偏差也能产生相同的效应。
