Fig. 2.
Conditions of Experiment 2 and Results. a–c The conditions of Experiment 2 were identical to those of Experiment 1, with the only difference being that the participants’ right hands, the sensor, and the slider were all placed 25 cm to the right of their left index fingers. As it has been shown that introducing such a distance between the hands eliminates somatosensory attenuation, we tested whether the same holds true for motor imagery. d Forces generated by participants (matched forces) as a function of the reference force (mean ± SE). There was no significant effect of condition on the participants’ performances, i.e., we found no evidence for somatosensory attenuation (see main text for detailed results). e Mean matched forces displayed per condition (mean ± SE). There were no significant differences among the three conditions. f Somatosensory attenuation expressed as the difference between the reference forces and the matched forces per condition (mean ± SE). g Root-mean-square EMG activity of the right FDI muscle averaged across all applications of the reference force per condition (mean ± SE). Importantly, no significant difference was detected between the basefar and imaginefar conditions, showing that the participants were able to relax their hand in the motor imagery condition