How does virtuality translate into reality?
This week in my bioelectricity class, we spoke about electrical stimulation of nerves. One method of stimulation is to place a electrode directly on the surface of a nerve. One of the considerations of this method, however, is that the anode (positively charged side) and cathode (negatively charged side) of the electrode each cause a redistribution of charge around the electrode. Consequently, the anode induces a complementary "virtual cathode" and the cathode creates a complementary "virtual anode." These components aren't actually there, but we can observe a similar redistribution of charge that implies that something unseen is going on. Despite the fact that these components are not physically present, they have real effects on the functionality of both the electrode and the nerve. The virtual cathode and anode can cause a very real, measurable voltage change in the nerve, and can effectively block a nerve signal, which is dependent on the voltage.
In what other ways can intangible entities have physical manifestations? In this case, the unintended effect has a negative consequence, but can we find useful applications of such a circumstance?
Also, if these imaginary aspects can effect reality, what does that say about our definition of what is real and what isn't?