Action and perception coupling

The general aim of this research theme is to understand the organizational principles sub serving the control of natural goal-oriented actions and how this control is implemented at physiological level. Two different experimental paradigms are applied: biological motion recognition and motion imitation.

People: Ambra Bisio, Marco Jacono

1) Biological motion recognition through the technique of motion inference.
The starting hypothesis is the existence of a motor representation that includes stereotyped kinematic parameters and the consequent implicit capacity to discriminate between biological and non biological movements. During the experiment subject is asked to see a moving visual stimulus with different velocity profiles. After the 60% of its trajectory the visual stimulus disappeared and subject is instructed to make a reaching movement from the target starting point to its inferred final position.

Figure 1 Experimental set up.

2) Motion imitation.
The main purpose is to understand what people imitate when they see a movement before moving. Participants are asked to look at the movements of two different visual stimuli: a dot projected on a screen and an actor sited in front of them. Stimuli velocity varied during the experiments. When the motion ends they have to reach the stimuli final position. No constraints are given on how they have to perform the task. The occurrence of an implicit imitation of the previous motion is investigated

Figure 2 Experimental set up: a) dot movement observation b) actor movement observation

Kinematic and dynamic parameters are evaluated together with accuracy in pointing. Movements are captured with VICON and EMG activity is registered with a 32 channels =16x2 wireless system. Eye motion analyzer (Eyelink) will be soon integrated and synchronized with the visual display in order to superimpose in time and space eye and visual target movements.