School of Psychology, University of Kent, Canterbury, UK.
School of Psychology, Keele University, Keele, UK.
Psychophysiology. 2020 Dec;57(12):e13685. doi: 10.1111/psyp.13685. Epub 2020 Sep 17.
Perceptual multi-stability is characterized by alternating interpretations of an unchanging stimulus input. The reversal negativity (RN) and reversal positivity (RP) ERP components show differences in electrophysiological responses between trials on which participants experience a perceptual reversal of a multi-stable stimulus versus trials without a reversal (i.e., stable). However, it is unclear to what extent these two ERP components reflect reversal-related perceptual processing rather than task and response processes. To address this, we varied task and response requirements while measuring the RN and RP. In the standard reversal task, participants indicated whether they saw a perceptual reversal on each trial. In contrast, in the identity task participants reported perceived identity of the stimulus (e.g., face or vase) without any reference to reversals. In some blocks, reversal trials required a response whereas in other blocks stable trials required a response. We found that the RN appeared independently of task and response style. However, the early latency RP component was only present when participants responded manually. For non-response trials, a component was found during the same latency as the RP but with inverted polarity. Our results suggest that the early RP component is dependent on response-related processes rather than being a pure neural signature of perceptual processes related to endogenous perceptual reversals.
知觉多稳定性的特点是对不变刺激输入的交替解释。反转负性（RN）和反转正性（RP）ERP 成分在参与者经历多稳定刺激的知觉反转与没有反转（即稳定）的试验之间的电生理反应中表现出差异。然而，尚不清楚这两个 ERP 成分在多大程度上反映了与反转相关的知觉处理，而不是任务和反应过程。为了解决这个问题，我们在测量 RN 和 RP 的同时改变了任务和反应要求。在标准反转任务中，参与者在每次试验中指示他们是否看到了知觉反转。相比之下，在身份任务中，参与者报告了感知到的刺激的身份（例如，脸或花瓶），而没有任何与反转相关的参考。在一些块中，反转试验需要反应，而在其他块中，稳定试验需要反应。我们发现，RN 独立于任务和反应方式出现。然而，当参与者手动反应时，才会出现早期潜伏期 RP 成分。对于无反应试验，在与 RP 相同的潜伏期内发现了一个成分，但极性相反。我们的结果表明，早期 RP 成分依赖于与反应相关的过程，而不是与内源性知觉反转相关的知觉过程的纯神经特征。
