We propose a spectroscopic experiment to characterise the effect of electron-phonon coupling on the nuclear dynamics of Mg and B in the the MgB2 superconductor. The superconducting temperature of this layered material is anomalously high. An explanation to this feature has been proposed, based on a strong electron-phonon coupling constant connecting the chemical bonds in the B layer and the stretching nuclear vibrations in the same plane. This scenario suggests that the B and Mg nuclear dynamics are differently affected by the onset of the superconducting transition, and that the key to the interpretation of the properties of MgB2 lies in the anharmonicity and anisotropy of the atom local potential. Therefore, we request beam-time on the VESUVIO spectrometer to measure the momentum distributions of B and Mg and infer the shape of their local potential.