Scientific Institute, IRCCS E. Medea, Neuro-Oncological and Neuropsychological Rehabilitation Unit, Bosisio Parini, Lecco, Italy.
Scientific Institute, IRCCS E. Medea, Neuropsychiatry and Neurorehabilitation Unit, Bosisio Parini, Lecco, Italy.
Brain Struct Funct. 2021 Apr;226(3):671-684. doi: 10.1007/s00429-020-02198-0. Epub 2021 Jan 11.
Congenital or acquired cerebellum alterations are associated with a complex pattern of motor, cognitive and social disorders. These disturbances may reflect the involvement of the cerebellum in generating and updating the internal models that sub-serve-the prediction of sensory events. Here, we tested whether the cerebellar involvement in using contextual expectations to interpret ambiguous sensory sceneries is specific for social actions or also extends to physical events. We applied anodic, cathodic and sham cerebellar transcranial Direct Current Stimulation (ctDCS) to modulate the performance of an adult sample in two tasks requiring the prediction of social actions or moving shapes. For both tasks, in an earlier implicit-learning phase (familiarization), we manipulated the probability of co-occurrence between a particular action/shape and contextual elements, which could provide either strongly or moderately informative expectations. The use of these expectations was then tested when participants had to predict the unfolding of temporally occluded videos, in situations of perceptual uncertainty (testing). Results showed that in the testing, but not in the familiarization phase, cathodic as compared to anodic and sham ctDCS hindered participants' sensitivity in predicting actions embedded in strongly, but not moderately, informative contexts. Conversely, anodic as compared to sham ctDCS boosted the prediction of actions embedded in moderately, but not strongly, informative contexts. We observed no ctDCS effects for the shape prediction task, thus pointing to a specific involvement of the cerebellum in forming expectations related to social events. Our results encourage the exploration of rehabilitative effects of ctDCS in patients with social perception deficits.
先天性或获得性小脑改变与复杂的运动、认知和社会障碍有关。这些障碍可能反映了小脑在生成和更新内部模型方面的作用，这些模型用于预测感觉事件。在这里，我们测试了小脑是否参与使用上下文期望来解释模棱两可的感觉场景，这种参与是否特定于社会动作，还是也扩展到物理事件。我们应用阳极、阴极和假阴极小脑经颅直流电刺激（ctDCS）来调节成年样本在两个需要预测社会动作或移动形状的任务中的表现。在这两个任务中，在早期的隐含学习阶段（熟悉阶段），我们操纵了特定动作/形状与上下文元素之间共同出现的概率，这些元素可以提供强烈或适度的信息期望。然后，当参与者必须在感知不确定的情况下预测时间遮挡的视频展开时，测试了他们使用这些期望的情况（测试）。结果表明，在测试中，但不在熟悉阶段，与阳极和假阴极 ctDCS 相比，阴极 ctDCS 会阻碍参与者对强烈信息环境中嵌入的动作的敏感性预测，但不会对中度信息环境中嵌入的动作的敏感性预测造成影响。相反，与假阴极 ctDCS 相比，阳极 ctDCS 会促进对中度信息环境中嵌入的动作的预测，但不会对强烈信息环境中嵌入的动作的预测产生影响。我们没有观察到形状预测任务的 ctDCS 效应，因此指出小脑在形成与社会事件相关的期望方面的特定作用。我们的研究结果鼓励探索 ctDCS 在社会知觉缺陷患者中的康复效果。
