Psychology and Neuroscience of Cognition Research Unit, University of Liège, Liège, Belgium.
Department of Biological and Medical Psychology, University of Bergen, Bergen, Norway.
Cogn Neuropsychiatry. 2022 Jul;27(4):255-272. doi: 10.1080/13546805.2022.2031945. Epub 2022 Feb 4.
Individuals experiencing auditory hallucinations (AH) tend to perceive voices when exposed to random noise. However, the factors driving this tendency remain unclear. The present study examined the interaction of a top-down (expectations) and bottom-up (type of noise) process to better understand the mechanisms that underlie AH.
Fifty-two healthy individuals (29 with high proneness and 23 with low proneness to AH) completed a signal detection task, in which they listened to pre-recorded sentences. The last word was either masked by noise or only noise was presented without the word. Two types of noise existed (speech-related versus speech-unrelated frequencies) and words were characterised by either high or low levels of semantic expectation.
Participants with high proneness to AH showed a more liberal decision bias (i.e., they were more likely to report having heard a word) and poorer discrimination ability as compared to participants with low proneness to AH - but only when the word was masked by speech-related noises and the level of expectation was high. Further, the more liberal decision bias correlated negatively with the tendency to experience AH.
This novel paradigm demonstrated an interaction between top-down (level of expectation) and bottom-up (type of noise) processes, supporting current theoretical models of AH.
经历听觉幻觉（AH）的个体在暴露于随机噪声时往往会感知到声音。然而，驱动这种趋势的因素仍不清楚。本研究考察了自上而下（期望）和自下而上（噪声类型）过程的相互作用，以更好地理解AH 背后的机制。
52 名健康个体（29 名具有高 AH 倾向和 23 名具有低 AH 倾向）完成了一项信号检测任务，在该任务中他们听预先录制的句子。最后一个词被噪声掩盖，或者只有噪声而没有词。存在两种类型的噪声（与言语相关的与与言语无关的频率），并且词具有高低水平的语义期望。
与低 AH 倾向的参与者相比，具有高 AH 倾向的参与者表现出更宽松的决策偏差（即他们更有可能报告听到一个词）和较差的辨别能力 - 但仅当词被与言语相关的噪声掩盖并且期望水平较高时。此外，更宽松的决策偏差与经历 AH 的趋势呈负相关。
这个新的范式展示了自上而下（期望水平）和自下而上（噪声类型）过程之间的相互作用，支持了 AH 的当前理论模型。
