School of Psychology and Sport Science, Anglia Ruskin University, East Road,Cambridgeshire, Cambridge, CB1 1PT, UK.
Exp Brain Res. 2020 Mar;238(3):621-629. doi: 10.1007/s00221-020-05740-y. Epub 2020 Feb 3.
Previous research utilising a between-subjects design has indicated that the use of noise-dampening ear protectors might enhance interoceptive accuracy (IAcc). In the present study, we further examined this effect using a repeated-measures, within-participants design, and investigated potential mechanisms that might explain the effect. 50 participants completed the heartbeat tracking task (HTT) with and without the use of industrial ear protectors, in a counter-balanced order. Participants were asked to count the number of heartbeats occurring in five discrete time intervals of 25, 35, 45, 55 and 95 s, without feeling for a manual pulse. HTT scores were significantly higher when ear protectors were worn, and the improvement in performance was greatest for participants with lower baseline IAcc. The ear protectors were associated with significantly increased self-reported heartbeat audibility, task-related confidence and concentration, and decreased levels of distractibility. Heartbeat audibility was also correlated with HTT performance when the ear protectors were worn. Because the use of industrial ear defenders resulted in increased heartbeat audibility, this manipulation should not be used to assess causal hypotheses related to changes in IAcc. However, it may serve as a simple, non-invasive manipulation to assess the effects of 'externalised' interoceptive signals.
先前的研究采用了被试间设计，表明使用隔音耳塞可能会提高内感受准确性（IAcc）。在本研究中，我们进一步使用重复测量、被试内设计来检验这一效应，并探究可能解释该效应的潜在机制。50 名参与者以平衡顺序先后使用和不使用工业耳塞完成了心跳跟踪任务（HTT）。参与者被要求在 25、35、45、55 和 95 秒这五个离散时间间隔内不手动感知脉搏而计数心跳次数。佩戴耳塞时，HTT 得分显著提高，而内感受准确性较低的参与者的表现提升最大。耳塞佩戴者报告的心跳可听度、与任务相关的信心和专注度显著增加，而分心程度则降低。佩戴耳塞时，心跳可听度与 HTT 表现呈正相关。由于使用工业耳塞会增加心跳的可听度，因此不应将这种操作用于评估与 IAcc 变化相关的因果假设。然而，它可以作为一种简单、非侵入性的操作，用于评估“外化”内感受信号的影响。
