Benedetto Alessandro, Spinelli Donatella, Morrone M Concetta
Department of Neuroscience, Psychology, Pharmacology and Child Health, University of Florence, 50135 Florence, Italy Department of Translational Research on New Technologies in Medicines and Surgery, University of Pisa, Via San Zeno 31, 56123 Pisa, Italy Institute of Neuroscience, National Research Council (CNR), 56124 Pisa, Italy.
Department of Human Movement, Social and Health Sciences, University of Rome, 'Foro Italico', Pizza Lauro De Bosis 15, 00135, Rome, Italy IRCCS Santa Lucia Foundation, Rome, Italy.
Proc Biol Sci. 2016 May 25;283(1831). doi: 10.1098/rspb.2016.0692.
Recent evidence suggests that ongoing brain oscillations may be instrumental in binding and integrating multisensory signals. In this experiment, we investigated the temporal dynamics of visual-motor integration processes. We show that action modulates sensitivity to visual contrast discrimination in a rhythmic fashion at frequencies of about 5 Hz (in the theta range), for up to 1 s after execution of action. To understand the origin of the oscillations, we measured oscillations in contrast sensitivity at different levels of luminance, which is known to affect the endogenous brain rhythms, boosting the power of alpha-frequencies. We found that the frequency of oscillation in sensitivity increased at low luminance, probably reflecting the shift in mean endogenous brain rhythm towards higher frequencies. Importantly, both at high and at low luminance, contrast discrimination showed a rhythmic motor-induced suppression effect, with the suppression occurring earlier at low luminance. We suggest that oscillations play a key role in sensory-motor integration, and that the motor-induced suppression may reflect the first manifestation of a rhythmic oscillation.
最近的证据表明，持续的脑振荡可能有助于绑定和整合多感官信号。在本实验中，我们研究了视觉运动整合过程的时间动态。我们发现，动作执行后长达1秒的时间内，动作以约5赫兹（在θ范围内）的频率有节奏地调节对视觉对比度辨别力的敏感度。为了理解振荡的起源，我们测量了不同亮度水平下对比度敏感度的振荡情况，已知亮度会影响内源性脑节律，增强α频率的功率。我们发现，在低亮度下，敏感度的振荡频率增加，这可能反映了平均内源性脑节律向更高频率的转变。重要的是，无论在高亮度还是低亮度下，对比度辨别都显示出有节奏的运动诱导抑制效应，且在低亮度下抑制出现得更早。我们认为，振荡在感觉运动整合中起关键作用，运动诱导的抑制可能反映了有节奏振荡的最初表现。
