The general concept of time-dependent charge and current densities for the electrons in a molecule responding to electromagnetic fields is considered. It is shown that nuclear electric and electromagnetic shieldings, related to absorption intensity in infrared and vibrational circular dichroism spectroscopies, can be expressed in terms of density functions in real space. Plots of charge and current densities obtained by the theoretical methods developed in the present study are expected to provide a physical basis on the absorption process and simple tools for the interpretation of vibrational spectroscopy parameters.