As AI systems increasingly permeate high-stakes decision-making, the terminology regarding human involvement - Human-in-the-Loop (HITL), Human-on-the-Loop (HOTL), and Human Oversight - has become vexingly ambiguous. This ambiguity complicates interdisciplinary collaboration between computer science, law, philosophy, psychology, and sociology and can lead to regulatory uncertainty. We propose a clarification grounded in causal structure, focused on human involvement during the runtime of AI systems. The distinction between HITL and HOTL, we argue, is not primarily spatial but causal: HITL is constitutive (a human contribution is necessary for the decision output), while HOTL is corrective (external to the primary causal chain, capable of preventing or modifying outputs). Within HOTL, we distinguish three temporal modes - synchronous, asynchronous, and anticipatory - situated within a nested model of provider and deployer runtime that clarifies their different capacities for intervention. A second, orthogonal dimension captures cognitive integration: whether human and machine operate as complementary or hybrid intelligence, yielding four structurally distinct configurations. Finally, we distinguish these descriptive categories from the normative requirements they serve: statutory "Human Oversight" is a specific normative mode of HOTL that demands not merely a corrective causal position, but genuine preparedness and capacity for effective intervention. Because the same person may occupy both HITL and HOTL roles simultaneously, we argue that this role duality must be treated as a design problem requiring architectural and epistemic mitigation rather than mere acknowledgment.

翻译：随着人工智能系统日益渗透高风险决策领域，有关人类参与——人在回路（HITL）、人在回路上（HOTL）及人类监督——的术语已变得极其含混。这种模糊性阻碍了计算机科学、法学、哲学、心理学与社会学之间的跨学科协作，并可能导致监管不确定性。我们提出一种基于因果结构的澄清方法，聚焦于人工智能系统运行期间的人类参与。我们认为，HITL与HOTL之间的区别主要不在于空间维度，而在于因果维度：HITL是构成性的（人类贡献对决策输出不可或缺），而HOTL是纠正性的（处于主要因果链之外，能够阻止或修改输出）。在HOTL内部，我们区分了三种时间模式——同步、异步与预期性——并将其置于提供方与部署方运行时的嵌套模型中，以阐明其不同的干预能力。第二个正交维度捕捉认知整合：人与机器是以互补智能还是混合智能的方式运作，由此产生四种结构上不同的配置。最后，我们将这些描述性类别与其所服务的规范性要求区分开来：法定“人类监督”是HOTL的一种特定规范模式，它不仅要求一种纠正性的因果位置，更要求具备有效干预的切实准备与能力。由于同一人可能同时扮演HITL与HOTL角色，我们认为这种角色双重性必须被视为一个设计问题，需要架构与认知层面的缓解措施，而非仅仅予以承认。