Department of Experimental Psychology, Ghent University, Ghent, Belgium.
Department of Psychology, McGill University, Montreal, Quebec, Canada.
Q J Exp Psychol (Hove). 2023 Jan;76(1):15-27. doi: 10.1177/17470218221075632. Epub 2022 Feb 8.
Sensory feedback plays an important role in speech motor control. One of the main sources of evidence for this is studies in which online auditory feedback is perturbed during ongoing speech. In motor control, it is therefore crucial to distinguish between sensory feedback and externally generated sensory events. This is called source monitoring. Previous altered feedback studies have taken non-conscious source monitoring for granted, as automatic responses to altered sensory feedback imply that the feedback changes are processed as self-caused. However, the role of source monitoring is unclear. The current study investigated whether conscious source monitoring modulates responses to unexpected pitch changes in auditory feedback. During the first block, some participants spontaneously attributed the pitch shifts to themselves (self-blamers) while others attributed them to an external source (other-blamers). Before Block 2, all participants were informed that the pitch shifts were experimentally induced. The self-blamers then showed a reduction in response magnitude in Block 2 compared with Block 1, while the other-blamers did not. This suggests that conscious source monitoring modulates responses to altered auditory feedback, such that consciously ascribing feedback to oneself leads to larger compensation responses. These results can be accounted for within the dominant comparator framework, where conscious source monitoring could modulate the gain on sensory feedback. Alternatively, the results can be naturally explained from an inferential framework, where conscious knowledge may bias the priors in a Bayesian process to determine the most likely source of a sensory event.
感觉反馈在言语运动控制中起着重要作用。支持这一观点的主要证据之一是，在正在进行的言语过程中，对在线听觉反馈进行干扰的研究。因此，在运动控制中，区分感觉反馈和外部产生的感觉事件至关重要。这被称为来源监测。之前的改变反馈研究认为无意识来源监测是理所当然的，因为对改变的感觉反馈的自动反应意味着反馈变化被视为自我引起的。然而，来源监测的作用尚不清楚。本研究探讨了有意识的来源监测是否会调节对听觉反馈中意外音高变化的反应。在第一个块中，一些参与者自发地将音高变化归因于自己（自责者），而另一些参与者则归因于外部来源（他责者）。在第 2 块之前，所有参与者都被告知音高变化是实验诱导的。然后，自责者在第 2 块中的反应幅度与第 1 块相比有所减小，而他责者则没有。这表明有意识的来源监测调节了对改变的听觉反馈的反应，即有意识地将反馈归因于自己会导致更大的补偿反应。这些结果可以用主导比较器框架来解释，在该框架中，有意识的来源监测可以调节感觉反馈的增益。或者，从推理框架中可以自然地解释这些结果，在该框架中，有意识的知识可能会使贝叶斯过程中的先验知识产生偏差，以确定感觉事件的最可能来源。
