Perception is not the passive registration of incoming sensory data. Rather, it involves some analysis by synthesis, based on past experiences and context. One adaptive consequence of this arrangement is imagination—the ability to richly simulate sensory experiences, interrogate and manipulate those simulations, in service of action and decision making. In this paper, we will discuss one possible cost of this adaptation, namely hallucinations—perceptions without sensory stimulation, which characterize serious mental illnesses like schizophrenia, but which also occur in neurological illnesses, and—crucially for the present piece—are common also in the non-treatment-seeking population. We will draw upon a framework for imagination that distinguishes voluntary from non-voluntary experiences and explore the extent to which the varieties and features of hallucinations map onto this distinction, with a focus on auditory-verbal hallucinations (AVHs)—colloquially, hearing voices. We will propose that sense of agency for the act of imagining is key to meaningfully dissecting different forms and features of AVHs, and we will outline the neural, cognitive and phenomenological sequelae of this sense. We will conclude that a compelling unifying framework for action, perception and belief—predictive processing—can incorporate observations regarding sense of agency, imagination and hallucination.

This article is part of the theme issue ‘Offline perception: voluntary and spontaneous perceptual experiences without matching external stimulation’.

感知不是传入感官数据的被动注册。相反，它涉及一些综合分析，基于过去的经验和背景。这种安排的一个适应性结果是想象力——丰富地模拟感官体验、询问和操纵这些模拟的能力，以服务于行动和决策。在本文中，我们将讨论这种适应的一个可能成本，即幻觉——没有感觉刺激的知觉，这是精神分裂症等严重精神疾病的特征，但也发生在神经系统疾病中，而且——对于本文而言至关重要——在非寻求治疗的人群。我们将利用一个想象框架来区分自愿体验和非自愿体验，并探索幻觉的种类和特征在多大程度上映射到这种区别，重点是听觉-语言幻觉 (AVH)——通俗地说，就是听到声音。我们将提出想象行为的代理感是有意义地剖析 AVH 的不同形式和特征的关键，我们将概述这种感觉的神经、认知和现象学后遗症。我们将得出结论，一个令人信服的行动、感知和信念统一框架——预测处理——可以包含对代理感、想象力和幻觉的观察。我们将提出想象行为的代理感是有意义地剖析 AVH 的不同形式和特征的关键，我们将概述这种感觉的神经、认知和现象学后遗症。我们将得出结论，一个令人信服的行动、感知和信念统一框架——预测处理——可以包含对代理感、想象力和幻觉的观察。我们将提出想象行为的代理感是有意义地剖析 AVH 的不同形式和特征的关键，我们将概述这种感觉的神经、认知和现象学后遗症。我们将得出结论，一个令人信服的行动、感知和信念统一框架——预测处理——可以包含对代理感、想象力和幻觉的观察。

这篇文章是主题问题“离线感知：没有匹配外部刺激的自愿和自发的感知体验”的一部分。