Abstract
While much previous research has linked the attenuation of the MU rhythm (8-13Hz) to the observation of specific visual categories and even to a potential role in action observation via a putative mirror neuron system, much of this work has not considered what specific type of information might be coded in this oscillatory response when triggered via vision. Here, we ask whether the MU response discriminates the identity of familiar or unfamiliar graspable objects. In the present study, right-handed participants (N=27) viewed images of both familiar (apple, wine glass) and unfamiliar (cubie, smoothie) graspable objects, whilst performing an orthogonal task at fixation. Multivariate pattern analysis (MVPA) revealed significant decoding of familiar, but not unfamiliar, visual object categories in the mu rhythm oscillatory response. Thus, simply viewing familiar graspable objects may automatically trigger activation of associated haptic properties in sensorimotor areas. In addition, we report significant attenuation in the central beta band for both familiar and unfamiliar visual objects, but not in the mu rhythm. These findings highlight how analyzing two different aspects of the oscillatory response – either attenuation or the representation of information content – provide complementary views on the role of the mu rhythm in response to viewing graspable object categories.