Here we present the theoretical (electrochemical and polymeric) description of chronopotentiometric responses (under driven constant current) from reacting conducting polymers both, as films or taking part of electrochemical devices, that sense driving current and electrolyte concentration during reactive actuation. The attained sensing-actuation equations describe the potential, or the consumed electrical energy, evolution as a function of working and environmental variables: driving current, temperature, electrolyte concentration, or mechanical conditions. Good agreement between theoretical and experimental results is attained here by using polypyrrole films under flow of different currents or in different electrolyte concentrations. Being a general theoretical description, any reactive device based on the electrochemistry of conducting polymers or carbon based reactive compounds is expected to sense working and environmental conditions being described by those equations as tactile artificial muscles do. Only two connecting wires contain actuating (current) and sensing (potential) signals that are detected, simultaneously and at any actuating time, by the computer as mammalians brains do.