Hobot Justyna, Koculak Marcin, Paulewicz Borysław, Sandberg Kristian, Wierzchoń Michał
Consciousness Lab, Psychology Institute, Jagiellonian University, Krakow, Poland.
Perception and Neuroarchitectural Mapping Group, Center of Functionally Integrative Neuroscience, Aarhus University, Aarhus, Denmark.
Front Neurosci. 2020 Oct 15;14:580712. doi: 10.3389/fnins.2020.580712. eCollection 2020.
The influence of non-visual information on visual awareness judgments has recently gained substantial interest. Using single-pulse transcranial magnetic stimulation (TMS), we investigate the potential contribution of evidence from the motor system to judgment of visual awareness. We hypothesized that TMS-induced activity in the primary motor cortex (M1) would increase reported visual awareness as compared to the control condition. Additionally, we investigated whether TMS-induced motor-evoked potential (MEP) could measure accumulated evidence for stimulus perception. Following stimulus presentation and TMS, participants first rated their visual awareness verbally using the Perceptual Awareness Scale (PAS), after which they responded manually to a Gabor orientation identification task. Delivering TMS to M1 resulted in higher average awareness ratings as compared to the control condition, in both correct and incorrect identification task response trials, when the hand with which participants responded was contralateral to the stimulated hemisphere (TMS-response-congruent trials). This effect was accompanied by longer PAS response times (RTs), irrespective of the congruence between TMS and identification response. Moreover, longer identification RTs were observed in TMS-response-congruent trials in the M1 condition as compared to the control condition. Additionally, the amplitudes of MEPs were related to the awareness ratings when response congruence was taken into account. We argue that MEP can serve as an indirect measure of evidence accumulated for stimulus perception and that longer PAS RTs and higher amplitudes of MEPs in the M1 condition reflect integration of additional evidence with visual awareness judgment. In conclusion, we advocate that motor activity influences perceptual awareness judgments.
非视觉信息对视觉意识判断的影响最近引起了广泛关注。我们使用单脉冲经颅磁刺激（TMS），研究运动系统的证据对视觉意识判断的潜在贡献。我们假设，与对照条件相比，经颅磁刺激诱导的初级运动皮层（M1）活动会增加报告的视觉意识。此外，我们研究了经颅磁刺激诱导的运动诱发电位（MEP）是否可以测量刺激感知的累积证据。在刺激呈现和经颅磁刺激后，参与者首先使用感知意识量表（PAS）口头评定他们的视觉意识，然后手动对加博尔方向识别任务做出反应。当参与者做出反应的手与受刺激半球对侧时（经颅磁刺激-反应一致试验），在正确和错误识别任务反应试验中，与对照条件相比，对M1进行经颅磁刺激导致更高的平均意识评分。无论经颅磁刺激与识别反应之间是否一致，这种效应都伴随着更长的PAS反应时间（RTs）。此外，与对照条件相比，在M1条件下的经颅磁刺激-反应一致试验中观察到更长的识别RTs。此外，当考虑反应一致性时，运动诱发电位的幅度与意识评分相关。我们认为，运动诱发电位可以作为刺激感知累积证据的间接测量指标，并且在M1条件下更长的PAS反应时间和更高的运动诱发电位幅度反映了额外证据与视觉意识判断的整合。总之我们主张运动活动会影响感知意识判断。
