The role of conditioning in perceptual inference

我们大脑所能获得的感官数据从根本上说是一种贫乏的信息来源。然而，我们通常认为世界是丰富的、统一的和连贯的。为了产生这种连贯的感知，可以作为行为的可靠指南，我们的大脑需要推断感官数据背后的原因。因此，知觉通常被概念化为一种主动的推理过程，它使用内源性预测来“理解”可用的感觉数据。知觉推理是适应性的，因为这些预测不断被新的感官证据更新。很明显，这种适应过程应该由其结果来塑造，也就是说，一个接受者是与有利的还是不利的事件相关联。然而，令人惊讶的是，人们对这种条件反射在知觉推理中的作用知之甚少。目前的建议的关键假设是，知觉推理是一个积极的过程，是调制条件反射以类似的方式作为行为。除了这种类似操作性的条件反射（这里称为感知条件反射）之外，还假设一种经典条件反射（这里称为刺激条件反射）也可能在感知推理中发挥作用。本项目旨在通过一系列的行为和功能磁共振成像实验，以知觉模糊为范式，阐明知觉感受和刺激条件化在知觉推理中的作用。知觉条件反射与刺激条件反射的机制可以通过将知觉选择与金钱的输赢联系起来（就像操作性条件反射那样），或者通过将竞争意识的视觉刺激与金钱的输赢联系起来（就像经典条件反射那样）来解开。至关重要的是，主观知觉的变化，发生在观看模糊的刺激，将与客观的措施进行评估，以排除主观报告的潜在混淆影响。在行为上，感知将通过探测探测任务间接跟踪。为了提供一个客观的测量感知在神经水平上，功能磁共振成像数据的多变量模式分析将被用来解码感知特定的大脑信号的感知。此外，知觉推理条件反射的神经基础将与单变量统计方法结合有效连接模型进行研究。预期本研究将在行为和神经水平上为认知感受和刺激条件反射的可分离效应提供证据。 因此，拟议中的项目将进一步我们的机制的理解，有意识的知觉，揭示了迄今为止在很大程度上未开发的方面的知觉推理。这也将为未来研究情感障碍和精神分裂症等精神疾病中感知经验改变的机制铺平道路。

The sensory data available to our brains are a fundamentally impoverished source of information. However, we nonetheless usually experience our perception of the world as rich, unitary and coherent. To generate such coherent perception that can be used as a reliable guide to behaviour, our brains need to infer the causes underlying the sensory data. Perception is therefore commonly conceptualized as an active inferential process that uses endogenous predictions to 'make sense' of the available sensory data. Perceptual inference is adaptive in that these predictions are constantly updated by new sensory evidence. It seems obvious that such an adaptive process should be shaped by its consequences, that is, whether a percept is associated with favourable or aversive events. Surprisingly, however, little is known about the role of such conditioning in perceptual inference. The key assumption of the current proposal is that perceptual inference is an active process that is modulated by conditioning in a similar way as behaviour. In addition to such operant-like conditioning, which is here referred to as percept conditioning, it is also assumed that a form of classical conditioning (here: stimulus conditioning) may also play a role in perceptual inference. This project aims to elucidate the roles of percept and stimulus conditioning in perceptual inference using the paradigm of perceptual ambiguity in a series of behavioural and functional magnetic resonance imaging (fMRI) experiments. The mechanisms of percept vs. stimulus conditioning will be disentangled by either associating perceptual choices with monetary wins or losses, just as in operant conditioning; or by associating visual stimuli that compete for awareness with monetary wins or losses, as in classical conditioning. Crucially, subjective perceptual alternations that occur during the viewing of ambiguous stimuli will be assessed with objective measures in order to preclude potential confounding effects of subjective reports. Behaviourally, perception will be tracked indirectly with a probe detection task. To provide an objective measure of perception at the neural level, multivariate pattern analysis of fMRI data will be used to decode perception from percept-specific brain signals. Moreover, the neural basis of conditioning in perceptual inference will be investigated with a univariate statistical approach in conjunction with models of effective connectivity. It is expected that this research will provide evidence for dissociable effects of percept and stimulus conditioning both at the behavioural and the neural level. The proposed project will thus further our understanding of the mechanisms underlying conscious perception by shedding light on a hitherto largely unexplored aspect of perceptual inference. It will also pave the way for future research into the mechanisms underlying altered perceptual experience in psychiatric diseases such as affective disorders and schizophrenia.