Poster B97, Sunday, March 25, 8:00-10:00 am, Exhibit Hall C
Combining kinesthetic illusion and action observation to evoke cortical plasticity in the primary motor cortex
Ambra Bisio1, Monica Biggio1, Piero Ruggeri1, Laura Avanzino1, Marco Bove1; 1University of Genoa, Italy
In the present study action observation (AO) was combined the proprioceptive afferences, which were generated by means of a mechanical vibration able to evoke a kinesthetic illusion (KI) of movement. A proprioceptive stimulator was positioned over the extensor pollicis brevis muscle in order to evoke an illusory sensation of thumb abduction. The experiment was composed of two conditions where AO and KI could be either congruent or incongruent. In the congruent condition (AO-KI CONGR) participants observed a 10-sec video showing the thumb abduction of the right hand (generated by the activation of the abductor pollicis brevis muscle - APB), whilst in the incongruent condition (AO-KI INCONGR) they observed a thumb adduction. The activity of the primary motors cortex (M1) in correspondence to the APB muscle area was evaluated by means of recruitment curves before, immediately after, and 30 and 60 minutes after the end of the stimulation. The results showed a significant increase of the M1 excitability that lasted until 60 minutes after AO-KI CONGR. No differences were observed before and after the administration of AO-KI INCONGR. Furthermore, in a control experiment the specificity for the kind of sensory input was tested, and a tactile vibration was delivered during the observation of thumb abduction. No changes to M1 excitability were observed. Therefore, AO when combined to KI evoked by a proprioceptive stimulation, was able to evoke plastic changes in M1 activity. These findings suggest that AO and KI likely act on the same neural circuitry inducing long-term plasticity effects.
Topic Area: PERCEPTION & ACTION: Multisensory