Institute for Experimental Psychology, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
Institute of Clinical Neuroscience and Medical Psychology, Medical Faculty, Heinrich Heine University Düsseldorf, Düsseldorf, Germany.
J Vis. 2022 Sep 2;22(10):10. doi: 10.1167/jov.22.10.10.
Saccades let the visual scene sweep with high speed across the retina, thus producing a massive motion stimulus. Yet, in natural vision, we never perceive motion that is produced by saccades. The absence of perisaccadic motion perception might be caused by a transient reduction of visual sensitivity at the time of saccade initiation, so-called saccadic suppression. Saccade suppression occurs for contrast, displacement, and motion stimuli. Saccade suppression of displacements has been shown to be context sensitive. After performing saccades in sessions without perisaccadic stimulation, saccade suppression magnitude is drastically decreased (Zimmermann, 2020). Here, we aimed to test whether saccade suppression of contrast is similarly modulated by context. To this end, we projected stimuli on a homogeneously white wall such that we could establish a ganzfeld-like environment that, depending on the experimental session, did or did not contain any visible contrast stimuli. We first successfully replicated the context sensitivity of saccade suppression of displacements. Then, we tested context sensitivity of contrast suppression by asking subjects to perform several saccades either across the uniform white wall or across a background consisting of a sinusoidal grating. In contrast to perisaccadic context sensitivity for displacement suppression, we did not find context sensitivity for suppression of contrast.
扫视让视觉场景以高速扫过视网膜，从而产生大量的运动刺激。然而，在自然视觉中，我们从未感知到由扫视产生的运动。在扫视开始时，视觉敏感性会暂时降低，从而导致扫视期间运动感知缺失，这种现象被称为扫视抑制。扫视抑制会发生在对比度、位移和运动刺激中。已经证明，位移的扫视抑制具有上下文敏感性。在没有扫视刺激的 sessions 中进行扫视后，扫视抑制的幅度会大幅降低（Zimmermann，2020）。在这里，我们旨在测试对比度的扫视抑制是否也受到上下文的调制。为此，我们将刺激投影到均匀的白色墙壁上，以便可以建立一个类似于全视野的环境，该环境根据实验 session 的不同，包含或不包含任何可见的对比度刺激。我们首先成功复制了位移扫视抑制的上下文敏感性。然后，我们通过要求受试者在均匀的白色墙壁或正弦光栅组成的背景上进行几次扫视，来测试对比度抑制的上下文敏感性。与位移抑制的扫视期间上下文敏感性不同，我们没有发现对比度抑制的上下文敏感性。
