**1. Introduction**

Interacting with an assistive or rehabilitation device involves an adaptation of the cognitive and sensorimotor skills of the human being. This fact suggests that a successful development of such a system should imply transdisciplinary studies that consider both technological and psychological issues. **Figure 1** is a systematic representation that describes the phenomena that occur when an individual has to carry out an action mediated through an artefact [1]. Natural mechanisms enable the users to adapt their behaviours to the new situation. Nevertheless, this natural phenomenon presents certain limits and artificial implementations which could be necessary to reduce the gap between the human operator and the machine. The next two sections explain the processes that underlie the natural adaptation

#### **Figure 1.**

*Natural and artificial processes of adaptation that emerge or can be implemented in a context of human-machine interaction.*

happening during the interaction with a tool and how this adaptation can be boosted by technological transformations of the artefact based on an anthropocentric approach.
